mpeg12dec.c 108 KB
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/*
 * MPEG-1/2 decoder
 * Copyright (c) 2000, 2001 Fabrice Bellard
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 * Copyright (c) 2002-2013 Michael Niedermayer <michaelni@gmx.at>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * MPEG-1/2 decoder
 */

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#define UNCHECKED_BITSTREAM_READER 1
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#include <inttypes.h>

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#include "libavutil/attributes.h"
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#include "libavutil/imgutils.h"
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#include "libavutil/internal.h"
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#include "libavutil/stereo3d.h"
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#include "avcodec.h"
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#include "bytestream.h"
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#include "error_resilience.h"
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#include "idctdsp.h"
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#include "internal.h"
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#include "mpeg_er.h"
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#include "mpeg12.h"
#include "mpeg12data.h"
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#include "mpegutils.h"
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#include "mpegvideo.h"
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#include "mpegvideodata.h"
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#include "thread.h"
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#include "version.h"
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#include "vdpau_compat.h"
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#include "xvmc_internal.h"
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typedef struct Mpeg1Context {
    MpegEncContext mpeg_enc_ctx;
    int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
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    int repeat_field;           /* true if we must repeat the field */
    AVPanScan pan_scan;         /* some temporary storage for the panscan */
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    AVStereo3D stereo3d;
    int has_stereo3d;
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    uint8_t *a53_caption;
    int a53_caption_size;
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    uint8_t afd;
    int has_afd;
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    int slice_count;
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    AVRational save_aspect;
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    int save_width, save_height, save_progressive_seq;
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    AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
    int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
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    int tmpgexs;
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    int first_slice;
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    int extradata_decoded;
} Mpeg1Context;

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#define MB_TYPE_ZERO_MV   0x20000000

static const uint32_t ptype2mb_type[7] = {
                    MB_TYPE_INTRA,
                    MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
                    MB_TYPE_L0,
                    MB_TYPE_L0 | MB_TYPE_CBP,
    MB_TYPE_QUANT | MB_TYPE_INTRA,
    MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
    MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
};

static const uint32_t btype2mb_type[11] = {
                    MB_TYPE_INTRA,
                    MB_TYPE_L1,
                    MB_TYPE_L1   | MB_TYPE_CBP,
                    MB_TYPE_L0,
                    MB_TYPE_L0   | MB_TYPE_CBP,
                    MB_TYPE_L0L1,
                    MB_TYPE_L0L1 | MB_TYPE_CBP,
    MB_TYPE_QUANT | MB_TYPE_INTRA,
    MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
    MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
    MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
};

static const uint8_t non_linear_qscale[32] = {
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     0,  1,  2,  3,  4,  5,   6,   7,
     8, 10, 12, 14, 16, 18,  20,  22,
    24, 28, 32, 36, 40, 44,  48,  52,
    56, 64, 72, 80, 88, 96, 104, 112,
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};

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/* as H.263, but only 17 codes */
static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
{
    int code, sign, val, shift;

    code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
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    if (code == 0)
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        return pred;
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    if (code < 0)
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        return 0xffff;

    sign  = get_bits1(&s->gb);
    shift = fcode - 1;
    val   = code;
    if (shift) {
        val  = (val - 1) << shift;
        val |= get_bits(&s->gb, shift);
        val++;
    }
    if (sign)
        val = -val;
    val += pred;

    /* modulo decoding */
    return sign_extend(val, 5 + shift);
}

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#define check_scantable_index(ctx, x)                                         \
    do {                                                                      \
        if ((x) > 63) {                                                       \
            av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
                   ctx->mb_x, ctx->mb_y);                                     \
            return AVERROR_INVALIDDATA;                                       \
        }                                                                     \
    } while (0)

static inline int mpeg1_decode_block_intra(MpegEncContext *s,
                                           int16_t *block, int n)
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{
    int level, dc, diff, i, j, run;
    int component;
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    RLTable *rl                  = &ff_rl_mpeg1;
    uint8_t *const scantable     = s->intra_scantable.permutated;
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    const uint16_t *quant_matrix = s->intra_matrix;
    const int qscale             = s->qscale;

    /* DC coefficient */
    component = (n <= 3 ? 0 : n - 4 + 1);
    diff = decode_dc(&s->gb, component);
    if (diff >= 0xffff)
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        return AVERROR_INVALIDDATA;
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    dc  = s->last_dc[component];
    dc += diff;
    s->last_dc[component] = dc;
    block[0] = dc * quant_matrix[0];
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    ff_tlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
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    i = 0;
    {
        OPEN_READER(re, &s->gb);
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        UPDATE_CACHE(re, &s->gb);
        if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
            goto end;

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        /* now quantify & encode AC coefficients */
        for (;;) {
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            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
                       TEX_VLC_BITS, 2, 0);
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            if (level != 0) {
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                i += run;
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                check_scantable_index(s, i);
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                j = scantable[i];
                level = (level * qscale * quant_matrix[j]) >> 4;
                level = (level - 1) | 1;
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                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
                        SHOW_SBITS(re, &s->gb, 1);
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                SKIP_BITS(re, &s->gb, 1);
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            } else {
                /* escape */
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                run = SHOW_UBITS(re, &s->gb, 6) + 1;
                LAST_SKIP_BITS(re, &s->gb, 6);
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                UPDATE_CACHE(re, &s->gb);
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                level = SHOW_SBITS(re, &s->gb, 8);
                SKIP_BITS(re, &s->gb, 8);
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                if (level == -128) {
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                    level = SHOW_UBITS(re, &s->gb, 8) - 256;
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                    SKIP_BITS(re, &s->gb, 8);
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                } else if (level == 0) {
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                    level = SHOW_UBITS(re, &s->gb, 8);
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                    SKIP_BITS(re, &s->gb, 8);
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                }
                i += run;
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                check_scantable_index(s, i);
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                j = scantable[i];
                if (level < 0) {
                    level = -level;
                    level = (level * qscale * quant_matrix[j]) >> 4;
                    level = (level - 1) | 1;
                    level = -level;
                } else {
                    level = (level * qscale * quant_matrix[j]) >> 4;
                    level = (level - 1) | 1;
                }
            }

            block[j] = level;
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            if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
               break;

            UPDATE_CACHE(re, &s->gb);
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        }
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end:
        LAST_SKIP_BITS(re, &s->gb, 2);
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        CLOSE_READER(re, &s->gb);
    }
    s->block_last_index[n] = i;
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    return 0;
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}

int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
{
    return mpeg1_decode_block_intra(s, block, n);
}

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static inline int mpeg1_decode_block_inter(MpegEncContext *s,
                                           int16_t *block, int n)
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{
    int level, i, j, run;
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    RLTable *rl                  = &ff_rl_mpeg1;
    uint8_t *const scantable     = s->intra_scantable.permutated;
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    const uint16_t *quant_matrix = s->inter_matrix;
    const int qscale             = s->qscale;

    {
        OPEN_READER(re, &s->gb);
        i = -1;
        // special case for first coefficient, no need to add second VLC table
        UPDATE_CACHE(re, &s->gb);
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        if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
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            level = (3 * qscale * quant_matrix[0]) >> 5;
            level = (level - 1) | 1;
            if (GET_CACHE(re, &s->gb) & 0x40000000)
                level = -level;
            block[0] = level;
            i++;
            SKIP_BITS(re, &s->gb, 2);
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            if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
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                goto end;
        }
        /* now quantify & encode AC coefficients */
        for (;;) {
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            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
                       TEX_VLC_BITS, 2, 0);
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            if (level != 0) {
                i += run;
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                check_scantable_index(s, i);
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                j = scantable[i];
                level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
                level = (level - 1) | 1;
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                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
                        SHOW_SBITS(re, &s->gb, 1);
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                SKIP_BITS(re, &s->gb, 1);
            } else {
                /* escape */
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                run = SHOW_UBITS(re, &s->gb, 6) + 1;
                LAST_SKIP_BITS(re, &s->gb, 6);
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                UPDATE_CACHE(re, &s->gb);
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                level = SHOW_SBITS(re, &s->gb, 8);
                SKIP_BITS(re, &s->gb, 8);
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                if (level == -128) {
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                    level = SHOW_UBITS(re, &s->gb, 8) - 256;
                    SKIP_BITS(re, &s->gb, 8);
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                } else if (level == 0) {
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                    level = SHOW_UBITS(re, &s->gb, 8);
                    SKIP_BITS(re, &s->gb, 8);
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                }
                i += run;
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                check_scantable_index(s, i);
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                j = scantable[i];
                if (level < 0) {
                    level = -level;
                    level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
                    level = (level - 1) | 1;
                    level = -level;
                } else {
                    level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
                    level = (level - 1) | 1;
                }
            }

            block[j] = level;
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            if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
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                break;
            UPDATE_CACHE(re, &s->gb);
        }
end:
        LAST_SKIP_BITS(re, &s->gb, 2);
        CLOSE_READER(re, &s->gb);
    }
    s->block_last_index[n] = i;
    return 0;
}

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/**
 * Note: this function can read out of range and crash for corrupt streams.
 * Changing this would eat up any speed benefits it has.
 * Do not use "fast" flag if you need the code to be robust.
 */
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static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
                                                int16_t *block, int n)
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{
    int level, i, j, run;
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    RLTable *rl              = &ff_rl_mpeg1;
    uint8_t *const scantable = s->intra_scantable.permutated;
    const int qscale         = s->qscale;
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    {
        OPEN_READER(re, &s->gb);
        i = -1;
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        // Special case for first coefficient, no need to add second VLC table.
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        UPDATE_CACHE(re, &s->gb);
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        if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
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            level = (3 * qscale) >> 1;
            level = (level - 1) | 1;
            if (GET_CACHE(re, &s->gb) & 0x40000000)
                level = -level;
            block[0] = level;
            i++;
            SKIP_BITS(re, &s->gb, 2);
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            if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
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                goto end;
        }

        /* now quantify & encode AC coefficients */
        for (;;) {
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            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
                       TEX_VLC_BITS, 2, 0);
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            if (level != 0) {
                i += run;
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                check_scantable_index(s, i);
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                j = scantable[i];
                level = ((level * 2 + 1) * qscale) >> 1;
                level = (level - 1) | 1;
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                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
                        SHOW_SBITS(re, &s->gb, 1);
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                SKIP_BITS(re, &s->gb, 1);
            } else {
                /* escape */
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                run = SHOW_UBITS(re, &s->gb, 6) + 1;
                LAST_SKIP_BITS(re, &s->gb, 6);
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                UPDATE_CACHE(re, &s->gb);
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                level = SHOW_SBITS(re, &s->gb, 8);
                SKIP_BITS(re, &s->gb, 8);
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                if (level == -128) {
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                    level = SHOW_UBITS(re, &s->gb, 8) - 256;
                    SKIP_BITS(re, &s->gb, 8);
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                } else if (level == 0) {
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                    level = SHOW_UBITS(re, &s->gb, 8);
                    SKIP_BITS(re, &s->gb, 8);
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                }
                i += run;
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                check_scantable_index(s, i);
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                j = scantable[i];
                if (level < 0) {
                    level = -level;
                    level = ((level * 2 + 1) * qscale) >> 1;
                    level = (level - 1) | 1;
                    level = -level;
                } else {
                    level = ((level * 2 + 1) * qscale) >> 1;
                    level = (level - 1) | 1;
                }
            }

            block[j] = level;
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            if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
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                break;
            UPDATE_CACHE(re, &s->gb);
        }
end:
        LAST_SKIP_BITS(re, &s->gb, 2);
        CLOSE_READER(re, &s->gb);
    }
    s->block_last_index[n] = i;
    return 0;
}

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static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
                                               int16_t *block, int n)
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{
    int level, i, j, run;
    RLTable *rl = &ff_rl_mpeg1;
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    uint8_t *const scantable = s->intra_scantable.permutated;
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    const uint16_t *quant_matrix;
    const int qscale = s->qscale;
    int mismatch;

    mismatch = 1;

    {
        OPEN_READER(re, &s->gb);
        i = -1;
        if (n < 4)
            quant_matrix = s->inter_matrix;
        else
            quant_matrix = s->chroma_inter_matrix;

415
        // Special case for first coefficient, no need to add second VLC table.
416
        UPDATE_CACHE(re, &s->gb);
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        if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
            level = (3 * qscale * quant_matrix[0]) >> 5;
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            if (GET_CACHE(re, &s->gb) & 0x40000000)
                level = -level;
            block[0]  = level;
            mismatch ^= level;
            i++;
            SKIP_BITS(re, &s->gb, 2);
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            if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
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                goto end;
        }

        /* now quantify & encode AC coefficients */
        for (;;) {
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            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
                       TEX_VLC_BITS, 2, 0);
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            if (level != 0) {
                i += run;
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                check_scantable_index(s, i);
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                j = scantable[i];
                level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
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                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
                        SHOW_SBITS(re, &s->gb, 1);
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                SKIP_BITS(re, &s->gb, 1);
            } else {
                /* escape */
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                run = SHOW_UBITS(re, &s->gb, 6) + 1;
                LAST_SKIP_BITS(re, &s->gb, 6);
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                UPDATE_CACHE(re, &s->gb);
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                level = SHOW_SBITS(re, &s->gb, 12);
                SKIP_BITS(re, &s->gb, 12);
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                i += run;
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                check_scantable_index(s, i);
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                j = scantable[i];
                if (level < 0) {
                    level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
                    level = -level;
                } else {
                    level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
                }
            }

            mismatch ^= level;
            block[j]  = level;
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            if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
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                break;
            UPDATE_CACHE(re, &s->gb);
        }
end:
        LAST_SKIP_BITS(re, &s->gb, 2);
        CLOSE_READER(re, &s->gb);
    }
    block[63] ^= (mismatch & 1);

    s->block_last_index[n] = i;
    return 0;
}

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/**
 * Note: this function can read out of range and crash for corrupt streams.
 * Changing this would eat up any speed benefits it has.
 * Do not use "fast" flag if you need the code to be robust.
 */
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static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
                                                    int16_t *block, int n)
{
    int level, i, j, run;
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    RLTable *rl              = &ff_rl_mpeg1;
    uint8_t *const scantable = s->intra_scantable.permutated;
    const int qscale         = s->qscale;
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    OPEN_READER(re, &s->gb);
    i = -1;

    // special case for first coefficient, no need to add second VLC table
    UPDATE_CACHE(re, &s->gb);
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    if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
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        level = (3 * qscale) >> 1;
        if (GET_CACHE(re, &s->gb) & 0x40000000)
            level = -level;
        block[0] = level;
        i++;
        SKIP_BITS(re, &s->gb, 2);
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        if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
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            goto end;
    }

    /* now quantify & encode AC coefficients */
    for (;;) {
        GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);

        if (level != 0) {
            i += run;
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            j = scantable[i];
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            level = ((level * 2 + 1) * qscale) >> 1;
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            level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
                    SHOW_SBITS(re, &s->gb, 1);
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            SKIP_BITS(re, &s->gb, 1);
        } else {
            /* escape */
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            run = SHOW_UBITS(re, &s->gb, 6) + 1;
            LAST_SKIP_BITS(re, &s->gb, 6);
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            UPDATE_CACHE(re, &s->gb);
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            level = SHOW_SBITS(re, &s->gb, 12);
            SKIP_BITS(re, &s->gb, 12);
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            i += run;
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            j = scantable[i];
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            if (level < 0) {
                level = ((-level * 2 + 1) * qscale) >> 1;
                level = -level;
            } else {
                level = ((level * 2 + 1) * qscale) >> 1;
            }
        }

        block[j] = level;
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        if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF || i > 63)
536
            break;
537

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        UPDATE_CACHE(re, &s->gb);
    }
end:
    LAST_SKIP_BITS(re, &s->gb, 2);
    CLOSE_READER(re, &s->gb);
    s->block_last_index[n] = i;
    return 0;
}

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static inline int mpeg2_decode_block_intra(MpegEncContext *s,
                                           int16_t *block, int n)
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{
    int level, dc, diff, i, j, run;
    int component;
    RLTable *rl;
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    uint8_t *const scantable = s->intra_scantable.permutated;
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    const uint16_t *quant_matrix;
    const int qscale = s->qscale;
    int mismatch;

    /* DC coefficient */
    if (n < 4) {
        quant_matrix = s->intra_matrix;
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        component    = 0;
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    } else {
        quant_matrix = s->chroma_intra_matrix;
564
        component    = (n & 1) + 1;
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    }
    diff = decode_dc(&s->gb, component);
    if (diff >= 0xffff)
568
        return AVERROR_INVALIDDATA;
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    dc  = s->last_dc[component];
    dc += diff;
    s->last_dc[component] = dc;
    block[0] = dc << (3 - s->intra_dc_precision);
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    ff_tlog(s->avctx, "dc=%d\n", block[0]);
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    mismatch = block[0] ^ 1;
    i = 0;
    if (s->intra_vlc_format)
        rl = &ff_rl_mpeg2;
    else
        rl = &ff_rl_mpeg1;

    {
        OPEN_READER(re, &s->gb);
        /* now quantify & encode AC coefficients */
        for (;;) {
            UPDATE_CACHE(re, &s->gb);
586 587
            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
                       TEX_VLC_BITS, 2, 0);
588 589 590 591 592

            if (level == 127) {
                break;
            } else if (level != 0) {
                i += run;
593
                check_scantable_index(s, i);
594
                j = scantable[i];
595
                level = (level * qscale * quant_matrix[j]) >> 4;
596 597
                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
                        SHOW_SBITS(re, &s->gb, 1);
598 599 600
                LAST_SKIP_BITS(re, &s->gb, 1);
            } else {
                /* escape */
601 602
                run = SHOW_UBITS(re, &s->gb, 6) + 1;
                LAST_SKIP_BITS(re, &s->gb, 6);
603
                UPDATE_CACHE(re, &s->gb);
604 605
                level = SHOW_SBITS(re, &s->gb, 12);
                SKIP_BITS(re, &s->gb, 12);
606
                i += run;
607
                check_scantable_index(s, i);
608
                j = scantable[i];
609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627
                if (level < 0) {
                    level = (-level * qscale * quant_matrix[j]) >> 4;
                    level = -level;
                } else {
                    level = (level * qscale * quant_matrix[j]) >> 4;
                }
            }

            mismatch ^= level;
            block[j]  = level;
        }
        CLOSE_READER(re, &s->gb);
    }
    block[63] ^= mismatch & 1;

    s->block_last_index[n] = i;
    return 0;
}

628 629 630 631 632
/**
 * Note: this function can read out of range and crash for corrupt streams.
 * Changing this would eat up any speed benefits it has.
 * Do not use "fast" flag if you need the code to be robust.
 */
633 634
static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
                                                int16_t *block, int n)
635
{
636
    int level, dc, diff, i, j, run;
637 638
    int component;
    RLTable *rl;
639
    uint8_t *const scantable = s->intra_scantable.permutated;
640 641 642 643 644 645
    const uint16_t *quant_matrix;
    const int qscale = s->qscale;

    /* DC coefficient */
    if (n < 4) {
        quant_matrix = s->intra_matrix;
646
        component    = 0;
647 648
    } else {
        quant_matrix = s->chroma_intra_matrix;
649
        component    = (n & 1) + 1;
650 651 652
    }
    diff = decode_dc(&s->gb, component);
    if (diff >= 0xffff)
653
        return AVERROR_INVALIDDATA;
654 655 656 657
    dc = s->last_dc[component];
    dc += diff;
    s->last_dc[component] = dc;
    block[0] = dc << (3 - s->intra_dc_precision);
658
    i = 0;
659 660 661 662 663 664 665 666 667 668
    if (s->intra_vlc_format)
        rl = &ff_rl_mpeg2;
    else
        rl = &ff_rl_mpeg1;

    {
        OPEN_READER(re, &s->gb);
        /* now quantify & encode AC coefficients */
        for (;;) {
            UPDATE_CACHE(re, &s->gb);
669 670
            GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
                       TEX_VLC_BITS, 2, 0);
671

672
            if (level >= 64 || i > 63) {
673 674
                break;
            } else if (level != 0) {
675
                i += run;
676
                j = scantable[i];
677
                level = (level * qscale * quant_matrix[j]) >> 4;
678 679
                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
                        SHOW_SBITS(re, &s->gb, 1);
680 681 682
                LAST_SKIP_BITS(re, &s->gb, 1);
            } else {
                /* escape */
683 684
                run = SHOW_UBITS(re, &s->gb, 6) + 1;
                LAST_SKIP_BITS(re, &s->gb, 6);
685
                UPDATE_CACHE(re, &s->gb);
686 687
                level = SHOW_SBITS(re, &s->gb, 12);
                SKIP_BITS(re, &s->gb, 12);
688
                i += run;
689
                j = scantable[i];
690 691 692 693 694 695 696 697 698 699 700 701 702
                if (level < 0) {
                    level = (-level * qscale * quant_matrix[j]) >> 4;
                    level = -level;
                } else {
                    level = (level * qscale * quant_matrix[j]) >> 4;
                }
            }

            block[j] = level;
        }
        CLOSE_READER(re, &s->gb);
    }

703
    s->block_last_index[n] = i;
704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720
    return 0;
}

/******************************************/
/* decoding */

static inline int get_dmv(MpegEncContext *s)
{
    if (get_bits1(&s->gb))
        return 1 - (get_bits1(&s->gb) << 1);
    else
        return 0;
}

static inline int get_qscale(MpegEncContext *s)
{
    int qscale = get_bits(&s->gb, 5);
721
    if (s->q_scale_type)
722
        return non_linear_qscale[qscale];
723
    else
724 725 726 727 728 729 730 731 732 733 734 735 736 737
        return qscale << 1;
}


/* motion type (for MPEG-2) */
#define MT_FIELD 1
#define MT_FRAME 2
#define MT_16X8  2
#define MT_DMV   3

static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
{
    int i, j, k, cbp, val, mb_type, motion_type;
    const int mb_block_count = 4 + (1 << s->chroma_format);
738
    int ret;
739

740
    ff_tlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
741

742
    av_assert2(s->mb_skipped == 0);
743 744 745 746

    if (s->mb_skip_run-- != 0) {
        if (s->pict_type == AV_PICTURE_TYPE_P) {
            s->mb_skipped = 1;
747 748
            s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
                MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
749 750 751 752 753 754
        } else {
            int mb_type;

            if (s->mb_x)
                mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
            else
755 756
                // FIXME not sure if this is allowed in MPEG at all
                mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
757 758
            if (IS_INTRA(mb_type)) {
                av_log(s->avctx, AV_LOG_ERROR, "skip with previntra\n");
759
                return AVERROR_INVALIDDATA;
760
            }
761
            s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
762
                mb_type | MB_TYPE_SKIP;
763

764 765 766 767 768 769 770 771 772 773 774 775
            if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
                s->mb_skipped = 1;
        }

        return 0;
    }

    switch (s->pict_type) {
    default:
    case AV_PICTURE_TYPE_I:
        if (get_bits1(&s->gb) == 0) {
            if (get_bits1(&s->gb) == 0) {
776 777 778
                av_log(s->avctx, AV_LOG_ERROR,
                       "invalid mb type in I Frame at %d %d\n",
                       s->mb_x, s->mb_y);
779
                return AVERROR_INVALIDDATA;
780 781 782 783 784 785 786 787 788
            }
            mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
        } else {
            mb_type = MB_TYPE_INTRA;
        }
        break;
    case AV_PICTURE_TYPE_P:
        mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
        if (mb_type < 0) {
789 790
            av_log(s->avctx, AV_LOG_ERROR,
                   "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
791
            return AVERROR_INVALIDDATA;
792 793 794 795 796 797
        }
        mb_type = ptype2mb_type[mb_type];
        break;
    case AV_PICTURE_TYPE_B:
        mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
        if (mb_type < 0) {
798 799
            av_log(s->avctx, AV_LOG_ERROR,
                   "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
800
            return AVERROR_INVALIDDATA;
801 802 803 804
        }
        mb_type = btype2mb_type[mb_type];
        break;
    }
805
    ff_tlog(s->avctx, "mb_type=%x\n", mb_type);
806 807
//    motion_type = 0; /* avoid warning */
    if (IS_INTRA(mb_type)) {
808
        s->bdsp.clear_blocks(s->block[0]);
809

810
        if (!s->chroma_y_shift)
811
            s->bdsp.clear_blocks(s->block[6]);
812 813

        /* compute DCT type */
814 815 816
        // FIXME: add an interlaced_dct coded var?
        if (s->picture_structure == PICT_FRAME &&
            !s->frame_pred_frame_dct)
817 818 819 820 821 822 823 824
            s->interlaced_dct = get_bits1(&s->gb);

        if (IS_QUANT(mb_type))
            s->qscale = get_qscale(s);

        if (s->concealment_motion_vectors) {
            /* just parse them */
            if (s->picture_structure != PICT_FRAME)
825
                skip_bits1(&s->gb);  /* field select */
826

827 828 829 830 831 832 833 834
            s->mv[0][0][0]      =
            s->last_mv[0][0][0] =
            s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
                                                     s->last_mv[0][0][0]);
            s->mv[0][0][1]      =
            s->last_mv[0][0][1] =
            s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
                                                     s->last_mv[0][0][1]);
835

836
            check_marker(&s->gb, "after concealment_motion_vectors");
837 838 839 840
        } else {
            /* reset mv prediction */
            memset(s->last_mv, 0, sizeof(s->last_mv));
        }
841 842
        s->mb_intra = 1;
        // if 1, we memcpy blocks in xvmcvideo
843
        if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
844 845 846
            ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks

        if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
847
            if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
848
                for (i = 0; i < 6; i++)
849 850
                    mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
            } else {
851
                for (i = 0; i < mb_block_count; i++)
852 853
                    if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
                        return ret;
854 855
            }
        } else {
856
            for (i = 0; i < 6; i++)
857 858
                if ((ret = mpeg1_decode_block_intra(s, *s->pblocks[i], i)) < 0)
                    return ret;
859 860 861
        }
    } else {
        if (mb_type & MB_TYPE_ZERO_MV) {
862
            av_assert2(mb_type & MB_TYPE_CBP);
863 864 865

            s->mv_dir = MV_DIR_FORWARD;
            if (s->picture_structure == PICT_FRAME) {
866 867
                if (s->picture_structure == PICT_FRAME
                    && !s->frame_pred_frame_dct)
868 869 870
                    s->interlaced_dct = get_bits1(&s->gb);
                s->mv_type = MV_TYPE_16X16;
            } else {
871 872
                s->mv_type            = MV_TYPE_FIELD;
                mb_type              |= MB_TYPE_INTERLACED;
873 874 875 876 877 878 879 880 881 882
                s->field_select[0][0] = s->picture_structure - 1;
            }

            if (IS_QUANT(mb_type))
                s->qscale = get_qscale(s);

            s->last_mv[0][0][0] = 0;
            s->last_mv[0][0][1] = 0;
            s->last_mv[0][1][0] = 0;
            s->last_mv[0][1][1] = 0;
883 884
            s->mv[0][0][0]      = 0;
            s->mv[0][0][1]      = 0;
885
        } else {
886
            av_assert2(mb_type & MB_TYPE_L0L1);
887 888
            // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
            /* get additional motion vector type */
889
            if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct) {
890
                motion_type = MT_FRAME;
891
            } else {
892 893 894 895 896 897 898 899 900 901
                motion_type = get_bits(&s->gb, 2);
                if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
                    s->interlaced_dct = get_bits1(&s->gb);
            }

            if (IS_QUANT(mb_type))
                s->qscale = get_qscale(s);

            /* motion vectors */
            s->mv_dir = (mb_type >> 13) & 3;
902
            ff_tlog(s->avctx, "motion_type=%d\n", motion_type);
903 904 905
            switch (motion_type) {
            case MT_FRAME: /* or MT_16X8 */
                if (s->picture_structure == PICT_FRAME) {
906
                    mb_type   |= MB_TYPE_16x16;
907 908 909 910
                    s->mv_type = MV_TYPE_16X16;
                    for (i = 0; i < 2; i++) {
                        if (USES_LIST(mb_type, i)) {
                            /* MT_FRAME */
911 912 913 914 915 916 917 918 919 920
                            s->mv[i][0][0]      =
                            s->last_mv[i][0][0] =
                            s->last_mv[i][1][0] =
                                mpeg_decode_motion(s, s->mpeg_f_code[i][0],
                                                   s->last_mv[i][0][0]);
                            s->mv[i][0][1]      =
                            s->last_mv[i][0][1] =
                            s->last_mv[i][1][1] =
                                mpeg_decode_motion(s, s->mpeg_f_code[i][1],
                                                   s->last_mv[i][0][1]);
921 922 923 924 925 926 927 928
                            /* full_pel: only for MPEG-1 */
                            if (s->full_pel[i]) {
                                s->mv[i][0][0] <<= 1;
                                s->mv[i][0][1] <<= 1;
                            }
                        }
                    }
                } else {
929
                    mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958
                    s->mv_type = MV_TYPE_16X8;
                    for (i = 0; i < 2; i++) {
                        if (USES_LIST(mb_type, i)) {
                            /* MT_16X8 */
                            for (j = 0; j < 2; j++) {
                                s->field_select[i][j] = get_bits1(&s->gb);
                                for (k = 0; k < 2; k++) {
                                    val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
                                                             s->last_mv[i][j][k]);
                                    s->last_mv[i][j][k] = val;
                                    s->mv[i][j][k]      = val;
                                }
                            }
                        }
                    }
                }
                break;
            case MT_FIELD:
                s->mv_type = MV_TYPE_FIELD;
                if (s->picture_structure == PICT_FRAME) {
                    mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
                    for (i = 0; i < 2; i++) {
                        if (USES_LIST(mb_type, i)) {
                            for (j = 0; j < 2; j++) {
                                s->field_select[i][j] = get_bits1(&s->gb);
                                val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
                                                         s->last_mv[i][j][0]);
                                s->last_mv[i][j][0] = val;
                                s->mv[i][j][0]      = val;
959
                                ff_tlog(s->avctx, "fmx=%d\n", val);
960 961
                                val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
                                                         s->last_mv[i][j][1] >> 1);
962
                                s->last_mv[i][j][1] = 2 * val;
963
                                s->mv[i][j][1]      = val;
964
                                ff_tlog(s->avctx, "fmy=%d\n", val);
965 966 967 968
                            }
                        }
                    }
                } else {
969
                    av_assert0(!s->progressive_sequence);
970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985
                    mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
                    for (i = 0; i < 2; i++) {
                        if (USES_LIST(mb_type, i)) {
                            s->field_select[i][0] = get_bits1(&s->gb);
                            for (k = 0; k < 2; k++) {
                                val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
                                                         s->last_mv[i][0][k]);
                                s->last_mv[i][0][k] = val;
                                s->last_mv[i][1][k] = val;
                                s->mv[i][0][k]      = val;
                            }
                        }
                    }
                }
                break;
            case MT_DMV:
986
                if (s->progressive_sequence){
987
                    av_log(s->avctx, AV_LOG_ERROR, "MT_DMV in progressive_sequence\n");
988
                    return AVERROR_INVALIDDATA;
989
                }
990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039
                s->mv_type = MV_TYPE_DMV;
                for (i = 0; i < 2; i++) {
                    if (USES_LIST(mb_type, i)) {
                        int dmx, dmy, mx, my, m;
                        const int my_shift = s->picture_structure == PICT_FRAME;

                        mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
                                                s->last_mv[i][0][0]);
                        s->last_mv[i][0][0] = mx;
                        s->last_mv[i][1][0] = mx;
                        dmx = get_dmv(s);
                        my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
                                                 s->last_mv[i][0][1] >> my_shift);
                        dmy = get_dmv(s);


                        s->last_mv[i][0][1] = my << my_shift;
                        s->last_mv[i][1][1] = my << my_shift;

                        s->mv[i][0][0] = mx;
                        s->mv[i][0][1] = my;
                        s->mv[i][1][0] = mx; // not used
                        s->mv[i][1][1] = my; // not used

                        if (s->picture_structure == PICT_FRAME) {
                            mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;

                            // m = 1 + 2 * s->top_field_first;
                            m = s->top_field_first ? 1 : 3;

                            /* top -> top pred */
                            s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
                            s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
                            m = 4 - m;
                            s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
                            s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
                        } else {
                            mb_type |= MB_TYPE_16x16;

                            s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
                            s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
                            if (s->picture_structure == PICT_TOP_FIELD)
                                s->mv[i][2][1]--;
                            else
                                s->mv[i][2][1]++;
                        }
                    }
                }
                break;
            default:
1040 1041
                av_log(s->avctx, AV_LOG_ERROR,
                       "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1042
                return AVERROR_INVALIDDATA;
1043 1044 1045 1046 1047
            }
        }

        s->mb_intra = 0;
        if (HAS_CBP(mb_type)) {
1048
            s->bdsp.clear_blocks(s->block[0]);
1049 1050 1051

            cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
            if (mb_block_count > 6) {
1052 1053
                cbp <<= mb_block_count - 6;
                cbp  |= get_bits(&s->gb, mb_block_count - 6);
1054
                s->bdsp.clear_blocks(s->block[6]);
1055 1056
            }
            if (cbp <= 0) {
1057
                av_log(s->avctx, AV_LOG_ERROR,
1058
                       "invalid cbp %d at %d %d\n", cbp, s->mb_x, s->mb_y);
1059
                return AVERROR_INVALIDDATA;
1060 1061
            }

1062
            // if 1, we memcpy blocks in xvmcvideo
1063
            if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1064 1065 1066
                ff_xvmc_pack_pblocks(s, cbp);

            if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1067
                if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
1068
                    for (i = 0; i < 6; i++) {
1069
                        if (cbp & 32)
1070
                            mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1071
                        else
1072 1073 1074 1075
                            s->block_last_index[i] = -1;
                        cbp += cbp;
                    }
                } else {
1076
                    cbp <<= 12 - mb_block_count;
1077 1078 1079

                    for (i = 0; i < mb_block_count; i++) {
                        if (cbp & (1 << 11)) {
1080 1081
                            if ((ret = mpeg2_decode_block_non_intra(s, *s->pblocks[i], i)) < 0)
                                return ret;
1082 1083 1084 1085 1086 1087 1088
                        } else {
                            s->block_last_index[i] = -1;
                        }
                        cbp += cbp;
                    }
                }
            } else {
1089
                if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
1090
                    for (i = 0; i < 6; i++) {
1091
                        if (cbp & 32)
1092
                            mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1093
                        else
1094 1095 1096 1097 1098 1099
                            s->block_last_index[i] = -1;
                        cbp += cbp;
                    }
                } else {
                    for (i = 0; i < 6; i++) {
                        if (cbp & 32) {
1100 1101
                            if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
                                return ret;
1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121
                        } else {
                            s->block_last_index[i] = -1;
                        }
                        cbp += cbp;
                    }
                }
            }
        } else {
            for (i = 0; i < 12; i++)
                s->block_last_index[i] = -1;
        }
    }

    s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;

    return 0;
}

static av_cold int mpeg_decode_init(AVCodecContext *avctx)
{
1122
    Mpeg1Context *s    = avctx->priv_data;
1123 1124
    MpegEncContext *s2 = &s->mpeg_enc_ctx;

1125
    ff_mpv_decode_defaults(s2);
1126 1127 1128 1129

    if (   avctx->codec_tag != AV_RL32("VCR2")
        && avctx->codec_tag != AV_RL32("BW10"))
        avctx->coded_width = avctx->coded_height = 0; // do not trust dimensions from input
1130
    ff_mpv_decode_init(s2, avctx);
1131 1132

    s->mpeg_enc_ctx.avctx  = avctx;
1133 1134 1135 1136

    /* we need some permutation to store matrices,
     * until the decoder sets the real permutation. */
    ff_mpv_idct_init(s2);
1137 1138 1139 1140 1141 1142 1143
    ff_mpeg12_common_init(&s->mpeg_enc_ctx);
    ff_mpeg12_init_vlcs();

    s->mpeg_enc_ctx_allocated      = 0;
    s->mpeg_enc_ctx.picture_number = 0;
    s->repeat_field                = 0;
    s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1144
    avctx->color_range             = AVCOL_RANGE_MPEG;
1145 1146 1147
    return 0;
}

1148 1149
static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
                                             const AVCodecContext *avctx_from)
1150 1151 1152 1153 1154
{
    Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
    MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
    int err;

1155 1156 1157
    if (avctx == avctx_from               ||
        !ctx_from->mpeg_enc_ctx_allocated ||
        !s1->context_initialized)
1158 1159 1160
        return 0;

    err = ff_mpeg_update_thread_context(avctx, avctx_from);
1161 1162
    if (err)
        return err;
1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180

    if (!ctx->mpeg_enc_ctx_allocated)
        memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));

    if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
        s->picture_number++;

    return 0;
}

static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
                                 const uint8_t *new_perm)
{
    uint16_t temp_matrix[64];
    int i;

    memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));

1181
    for (i = 0; i < 64; i++)
1182 1183 1184
        matrix[new_perm[i]] = temp_matrix[old_perm[i]];
}

1185
static const enum AVPixelFormat mpeg1_hwaccel_pixfmt_list_420[] = {
1186 1187
#if CONFIG_MPEG1_XVMC_HWACCEL
    AV_PIX_FMT_XVMC,
1188
#endif
1189
#if CONFIG_MPEG1_VDPAU_DECODER && FF_API_VDPAU
1190
    AV_PIX_FMT_VDPAU_MPEG1,
1191 1192
#endif
#if CONFIG_MPEG1_VDPAU_HWACCEL
1193
    AV_PIX_FMT_VDPAU,
1194 1195 1196 1197
#endif
    AV_PIX_FMT_YUV420P,
    AV_PIX_FMT_NONE
};
1198

1199
static const enum AVPixelFormat mpeg2_hwaccel_pixfmt_list_420[] = {
1200 1201
#if CONFIG_MPEG2_XVMC_HWACCEL
    AV_PIX_FMT_XVMC,
1202
#endif
1203
#if CONFIG_MPEG_VDPAU_DECODER && FF_API_VDPAU
1204
    AV_PIX_FMT_VDPAU_MPEG2,
1205 1206
#endif
#if CONFIG_MPEG2_VDPAU_HWACCEL
1207
    AV_PIX_FMT_VDPAU,
1208
#endif
1209 1210 1211
#if CONFIG_MPEG2_DXVA2_HWACCEL
    AV_PIX_FMT_DXVA2_VLD,
#endif
1212 1213 1214
#if CONFIG_MPEG2_D3D11VA_HWACCEL
    AV_PIX_FMT_D3D11VA_VLD,
#endif
1215
#if CONFIG_MPEG2_VAAPI_HWACCEL
1216
    AV_PIX_FMT_VAAPI,
1217 1218 1219
#endif
#if CONFIG_MPEG2_VIDEOTOOLBOX_HWACCEL
    AV_PIX_FMT_VIDEOTOOLBOX,
1220 1221 1222 1223 1224
#endif
    AV_PIX_FMT_YUV420P,
    AV_PIX_FMT_NONE
};

1225 1226 1227 1228 1229 1230 1231 1232 1233 1234
static const enum AVPixelFormat mpeg12_pixfmt_list_422[] = {
    AV_PIX_FMT_YUV422P,
    AV_PIX_FMT_NONE
};

static const enum AVPixelFormat mpeg12_pixfmt_list_444[] = {
    AV_PIX_FMT_YUV444P,
    AV_PIX_FMT_NONE
};

1235
#if FF_API_VDPAU
1236 1237 1238
static inline int uses_vdpau(AVCodecContext *avctx) {
    return avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG1 || avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG2;
}
1239
#endif
1240

1241 1242
static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
{
1243
    Mpeg1Context *s1  = avctx->priv_data;
1244
    MpegEncContext *s = &s1->mpeg_enc_ctx;
1245
    const enum AVPixelFormat *pix_fmts;
1246

1247
    if (CONFIG_GRAY && (avctx->flags & AV_CODEC_FLAG_GRAY))
1248 1249
        return AV_PIX_FMT_GRAY8;

1250
    if (s->chroma_format < 2)
1251
        pix_fmts = avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO ?
1252
                                mpeg1_hwaccel_pixfmt_list_420 :
1253
                                mpeg2_hwaccel_pixfmt_list_420;
1254
    else if (s->chroma_format == 2)
1255
        pix_fmts = mpeg12_pixfmt_list_422;
1256
    else
1257 1258
        pix_fmts = mpeg12_pixfmt_list_444;

1259
    return ff_thread_get_format(avctx, pix_fmts);
1260 1261 1262 1263 1264
}

static void setup_hwaccel_for_pixfmt(AVCodecContext *avctx)
{
    // until then pix_fmt may be changed right after codec init
1265 1266 1267 1268 1269
    if (avctx->hwaccel
#if FF_API_VDPAU
        || uses_vdpau(avctx)
#endif
        )
1270 1271
        if (avctx->idct_algo == FF_IDCT_AUTO)
            avctx->idct_algo = FF_IDCT_SIMPLE;
1272 1273 1274 1275 1276 1277 1278

    if (avctx->hwaccel && avctx->pix_fmt == AV_PIX_FMT_XVMC) {
        Mpeg1Context *s1 = avctx->priv_data;
        MpegEncContext *s = &s1->mpeg_enc_ctx;

        s->pack_pblocks = 1;
#if FF_API_XVMC
1279
FF_DISABLE_DEPRECATION_WARNINGS
1280
        avctx->xvmc_acceleration = 2;
1281
FF_ENABLE_DEPRECATION_WARNINGS
1282 1283
#endif /* FF_API_XVMC */
    }
1284 1285 1286 1287 1288 1289
}

/* Call this function when we know all parameters.
 * It may be called in different places for MPEG-1 and MPEG-2. */
static int mpeg_decode_postinit(AVCodecContext *avctx)
{
1290
    Mpeg1Context *s1  = avctx->priv_data;
1291 1292
    MpegEncContext *s = &s1->mpeg_enc_ctx;
    uint8_t old_permutation[64];
1293
    int ret;
1294

1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324
    if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
        // MPEG-1 aspect
        avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
    } else { // MPEG-2
        // MPEG-2 aspect
        if (s->aspect_ratio_info > 1) {
            AVRational dar =
                av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
                                  (AVRational) { s1->pan_scan.width,
                                                 s1->pan_scan.height }),
                         (AVRational) { s->width, s->height });

            /* We ignore the spec here and guess a bit as reality does not
             * match the spec, see for example res_change_ffmpeg_aspect.ts
             * and sequence-display-aspect.mpg.
             * issue1613, 621, 562 */
            if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
                (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
                 av_cmp_q(dar, (AVRational) { 16, 9 }))) {
                s->avctx->sample_aspect_ratio =
                    av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
                             (AVRational) { s->width, s->height });
            } else {
                s->avctx->sample_aspect_ratio =
                    av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
                             (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
// issue1613 4/3 16/9 -> 16/9
// res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
// widescreen-issue562.mpg 4/3 16/9 -> 16/9
//                s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1325
                ff_dlog(avctx, "aspect A %d/%d\n",
1326 1327
                        ff_mpeg2_aspect[s->aspect_ratio_info].num,
                        ff_mpeg2_aspect[s->aspect_ratio_info].den);
1328
                ff_dlog(avctx, "aspect B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1329 1330 1331 1332 1333 1334 1335 1336
                        s->avctx->sample_aspect_ratio.den);
            }
        } else {
            s->avctx->sample_aspect_ratio =
                ff_mpeg2_aspect[s->aspect_ratio_info];
        }
    } // MPEG-2

1337 1338 1339 1340 1341 1342 1343
    if (av_image_check_sar(s->width, s->height,
                           avctx->sample_aspect_ratio) < 0) {
        av_log(avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
                avctx->sample_aspect_ratio.num,
                avctx->sample_aspect_ratio.den);
        avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
    }
1344

1345 1346 1347
    if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
        avctx->coded_width       != s->width                ||
        avctx->coded_height      != s->height               ||
1348 1349
        s1->save_width           != s->width                ||
        s1->save_height          != s->height               ||
1350
        av_cmp_q(s1->save_aspect, s->avctx->sample_aspect_ratio) ||
1351
        (s1->save_progressive_seq != s->progressive_sequence && FFALIGN(s->height, 16) != FFALIGN(s->height, 32)) ||
1352
        0) {
1353 1354 1355
        if (s1->mpeg_enc_ctx_allocated) {
            ParseContext pc = s->parse_context;
            s->parse_context.buffer = 0;
1356
            ff_mpv_common_end(s);
1357
            s->parse_context = pc;
1358
            s1->mpeg_enc_ctx_allocated = 0;
1359 1360
        }

1361 1362 1363 1364
        ret = ff_set_dimensions(avctx, s->width, s->height);
        if (ret < 0)
            return ret;

1365 1366 1367 1368 1369 1370
        if (avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO && s->bit_rate) {
            avctx->rc_max_rate = s->bit_rate;
        } else if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO && s->bit_rate &&
                   (s->bit_rate != 0x3FFFF*400 || s->vbv_delay != 0xFFFF)) {
            avctx->bit_rate = s->bit_rate;
        }
1371
        s1->save_aspect          = s->avctx->sample_aspect_ratio;
1372 1373 1374 1375 1376 1377 1378 1379 1380
        s1->save_width           = s->width;
        s1->save_height          = s->height;
        s1->save_progressive_seq = s->progressive_sequence;

        /* low_delay may be forced, in this case we will have B-frames
         * that behave like P-frames. */
        avctx->has_b_frames = !s->low_delay;

        if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1381
            // MPEG-1 fps
1382
            avctx->framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
1383
            avctx->ticks_per_frame     = 1;
1384 1385

            avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1386 1387
        } else { // MPEG-2
            // MPEG-2 fps
1388 1389
            av_reduce(&s->avctx->framerate.num,
                      &s->avctx->framerate.den,
1390
                      ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1391 1392 1393
                      ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
                      1 << 30);
            avctx->ticks_per_frame = 2;
1394 1395 1396 1397 1398

            switch (s->chroma_format) {
            case 1: avctx->chroma_sample_location = AVCHROMA_LOC_LEFT; break;
            case 2:
            case 3: avctx->chroma_sample_location = AVCHROMA_LOC_TOPLEFT; break;
1399
            default: av_assert0(0);
1400
            }
1401 1402 1403
        } // MPEG-2

        avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1404
        setup_hwaccel_for_pixfmt(avctx);
1405 1406 1407

        /* Quantization matrices may need reordering
         * if DCT permutation is changed. */
1408
        memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1409

1410
        ff_mpv_idct_init(s);
1411 1412
        if ((ret = ff_mpv_common_init(s)) < 0)
            return ret;
1413

1414 1415 1416 1417
        quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
        quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
        quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
        quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1418 1419 1420 1421 1422 1423

        s1->mpeg_enc_ctx_allocated = 1;
    }
    return 0;
}

1424 1425
static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
                                int buf_size)
1426
{
1427
    Mpeg1Context *s1  = avctx->priv_data;
1428 1429 1430
    MpegEncContext *s = &s1->mpeg_enc_ctx;
    int ref, f_code, vbv_delay;

1431
    init_get_bits(&s->gb, buf, buf_size * 8);
1432 1433 1434 1435

    ref = get_bits(&s->gb, 10); /* temporal ref */
    s->pict_type = get_bits(&s->gb, 3);
    if (s->pict_type == 0 || s->pict_type > 3)
1436
        return AVERROR_INVALIDDATA;
1437 1438

    vbv_delay = get_bits(&s->gb, 16);
1439
    s->vbv_delay = vbv_delay;
1440 1441
    if (s->pict_type == AV_PICTURE_TYPE_P ||
        s->pict_type == AV_PICTURE_TYPE_B) {
1442 1443
        s->full_pel[0] = get_bits1(&s->gb);
        f_code = get_bits(&s->gb, 3);
1444
        if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1445
            return AVERROR_INVALIDDATA;
1446
        f_code += !f_code;
1447 1448 1449 1450 1451 1452
        s->mpeg_f_code[0][0] = f_code;
        s->mpeg_f_code[0][1] = f_code;
    }
    if (s->pict_type == AV_PICTURE_TYPE_B) {
        s->full_pel[1] = get_bits1(&s->gb);
        f_code = get_bits(&s->gb, 3);
1453
        if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1454
            return AVERROR_INVALIDDATA;
1455
        f_code += !f_code;
1456 1457 1458
        s->mpeg_f_code[1][0] = f_code;
        s->mpeg_f_code[1][1] = f_code;
    }
1459 1460
    s->current_picture.f->pict_type = s->pict_type;
    s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1461 1462

    if (avctx->debug & FF_DEBUG_PICT_INFO)
1463 1464
        av_log(avctx, AV_LOG_DEBUG,
               "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1465 1466 1467 1468 1469 1470 1471 1472

    s->y_dc_scale = 8;
    s->c_dc_scale = 8;
    return 0;
}

static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
{
1473
    MpegEncContext *s = &s1->mpeg_enc_ctx;
1474 1475 1476 1477 1478 1479
    int horiz_size_ext, vert_size_ext;
    int bit_rate_ext;

    skip_bits(&s->gb, 1); /* profile and level esc*/
    s->avctx->profile       = get_bits(&s->gb, 3);
    s->avctx->level         = get_bits(&s->gb, 4);
1480
    s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1481
    s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1482 1483 1484 1485 1486 1487

    if (!s->chroma_format) {
        s->chroma_format = 1;
        av_log(s->avctx, AV_LOG_WARNING, "Chroma format invalid\n");
    }

1488 1489 1490 1491 1492
    horiz_size_ext          = get_bits(&s->gb, 2);
    vert_size_ext           = get_bits(&s->gb, 2);
    s->width  |= (horiz_size_ext << 12);
    s->height |= (vert_size_ext  << 12);
    bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1493
    s->bit_rate += (bit_rate_ext << 18) * 400LL;
1494
    check_marker(&s->gb, "after bit rate extension");
1495 1496 1497
    s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;

    s->low_delay = get_bits1(&s->gb);
1498
    if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
1499 1500 1501 1502 1503
        s->low_delay = 1;

    s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
    s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;

1504
    ff_dlog(s->avctx, "sequence extension\n");
1505
    s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1506 1507

    if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1508
        av_log(s->avctx, AV_LOG_DEBUG,
1509
               "profile: %d, level: %d ps: %d cf:%d vbv buffer: %d, bitrate:%"PRId64"\n",
1510
               s->avctx->profile, s->avctx->level, s->progressive_sequence, s->chroma_format,
1511
               s->avctx->rc_buffer_size, s->bit_rate);
1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526
}

static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
{
    MpegEncContext *s = &s1->mpeg_enc_ctx;
    int color_description, w, h;

    skip_bits(&s->gb, 3); /* video format */
    color_description = get_bits1(&s->gb);
    if (color_description) {
        s->avctx->color_primaries = get_bits(&s->gb, 8);
        s->avctx->color_trc       = get_bits(&s->gb, 8);
        s->avctx->colorspace      = get_bits(&s->gb, 8);
    }
    w = get_bits(&s->gb, 14);
1527
    skip_bits(&s->gb, 1); // marker
1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564
    h = get_bits(&s->gb, 14);
    // remaining 3 bits are zero padding

    s1->pan_scan.width  = 16 * w;
    s1->pan_scan.height = 16 * h;

    if (s->avctx->debug & FF_DEBUG_PICT_INFO)
        av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
}

static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
{
    MpegEncContext *s = &s1->mpeg_enc_ctx;
    int i, nofco;

    nofco = 1;
    if (s->progressive_sequence) {
        if (s->repeat_first_field) {
            nofco++;
            if (s->top_field_first)
                nofco++;
        }
    } else {
        if (s->picture_structure == PICT_FRAME) {
            nofco++;
            if (s->repeat_first_field)
                nofco++;
        }
    }
    for (i = 0; i < nofco; i++) {
        s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
        skip_bits(&s->gb, 1); // marker
        s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
        skip_bits(&s->gb, 1); // marker
    }

    if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1565 1566
        av_log(s->avctx, AV_LOG_DEBUG,
               "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1567 1568 1569 1570 1571
               s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
               s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
               s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
}

1572 1573
static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
                       uint16_t matrix1[64], int intra)
1574 1575 1576 1577
{
    int i;

    for (i = 0; i < 64; i++) {
1578
        int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1579 1580 1581
        int v = get_bits(&s->gb, 8);
        if (v == 0) {
            av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1582
            return AVERROR_INVALIDDATA;
1583 1584
        }
        if (intra && i == 0 && v != 8) {
1585
            av_log(s->avctx, AV_LOG_DEBUG, "intra matrix specifies invalid DC quantizer %d, ignoring\n", v);
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            v = 8; // needed by pink.mpg / issue1046
        }
        matrix0[j] = v;
        if (matrix1)
            matrix1[j] = v;
    }
    return 0;
}

static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
{
1597
    ff_dlog(s->avctx, "matrix extension\n");
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    if (get_bits1(&s->gb))
        load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
    if (get_bits1(&s->gb))
        load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
    if (get_bits1(&s->gb))
        load_matrix(s, s->chroma_intra_matrix, NULL, 1);
    if (get_bits1(&s->gb))
        load_matrix(s, s->chroma_inter_matrix, NULL, 0);
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}

static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
{
    MpegEncContext *s = &s1->mpeg_enc_ctx;

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    s->full_pel[0]       = s->full_pel[1] = 0;
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    s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
    s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
    s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
    s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
    if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
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        av_log(s->avctx, AV_LOG_ERROR,
               "Missing picture start code, guessing missing values\n");
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        if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
            if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
                s->pict_type = AV_PICTURE_TYPE_I;
            else
                s->pict_type = AV_PICTURE_TYPE_P;
        } else
            s->pict_type = AV_PICTURE_TYPE_B;
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        s->current_picture.f->pict_type = s->pict_type;
        s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1630
    }
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    s->mpeg_f_code[0][0] += !s->mpeg_f_code[0][0];
    s->mpeg_f_code[0][1] += !s->mpeg_f_code[0][1];
    s->mpeg_f_code[1][0] += !s->mpeg_f_code[1][0];
    s->mpeg_f_code[1][1] += !s->mpeg_f_code[1][1];

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    s->intra_dc_precision         = get_bits(&s->gb, 2);
    s->picture_structure          = get_bits(&s->gb, 2);
    s->top_field_first            = get_bits1(&s->gb);
    s->frame_pred_frame_dct       = get_bits1(&s->gb);
    s->concealment_motion_vectors = get_bits1(&s->gb);
    s->q_scale_type               = get_bits1(&s->gb);
    s->intra_vlc_format           = get_bits1(&s->gb);
    s->alternate_scan             = get_bits1(&s->gb);
    s->repeat_first_field         = get_bits1(&s->gb);
    s->chroma_420_type            = get_bits1(&s->gb);
    s->progressive_frame          = get_bits1(&s->gb);

    if (s->alternate_scan) {
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        ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
        ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1651
    } else {
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        ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
        ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
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    }

    /* composite display not parsed */
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    ff_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
    ff_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
    ff_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
    ff_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
    ff_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
    ff_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
    ff_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
    ff_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
    ff_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
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}

static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
{
    AVCodecContext *avctx = s->avctx;
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    Mpeg1Context *s1      = (Mpeg1Context *) s;
1672
    int ret;
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    /* start frame decoding */
    if (s->first_field || s->picture_structure == PICT_FRAME) {
        AVFrameSideData *pan_scan;

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        if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
            return ret;
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        ff_mpeg_er_frame_start(s);

        /* first check if we must repeat the frame */
1684
        s->current_picture_ptr->f->repeat_pict = 0;
1685 1686 1687
        if (s->repeat_first_field) {
            if (s->progressive_sequence) {
                if (s->top_field_first)
1688
                    s->current_picture_ptr->f->repeat_pict = 4;
1689
                else
1690
                    s->current_picture_ptr->f->repeat_pict = 2;
1691
            } else if (s->progressive_frame) {
1692
                s->current_picture_ptr->f->repeat_pict = 1;
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            }
        }

1696
        pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
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                                          AV_FRAME_DATA_PANSCAN,
                                          sizeof(s1->pan_scan));
        if (!pan_scan)
            return AVERROR(ENOMEM);
        memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));

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        if (s1->a53_caption) {
            AVFrameSideData *sd = av_frame_new_side_data(
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                s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
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                s1->a53_caption_size);
            if (sd)
                memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
            av_freep(&s1->a53_caption);
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            avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
1711
        }
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        if (s1->has_stereo3d) {
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            AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
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            if (!stereo)
                return AVERROR(ENOMEM);

            *stereo = s1->stereo3d;
            s1->has_stereo3d = 0;
        }
1721 1722

        if (s1->has_afd) {
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            AVFrameSideData *sd =
                av_frame_new_side_data(s->current_picture_ptr->f,
                                       AV_FRAME_DATA_AFD, 1);
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            if (!sd)
                return AVERROR(ENOMEM);

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            *sd->data   = s1->afd;
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            s1->has_afd = 0;
        }

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        if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
            ff_thread_finish_setup(avctx);
    } else { // second field
        int i;

        if (!s->current_picture_ptr) {
            av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
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            return AVERROR_INVALIDDATA;
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        }

        if (s->avctx->hwaccel &&
            (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
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1745
            if ((ret = s->avctx->hwaccel->end_frame(s->avctx)) < 0) {
1746 1747
                av_log(avctx, AV_LOG_ERROR,
                       "hardware accelerator failed to decode first field\n");
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                return ret;
            }
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        }

        for (i = 0; i < 4; i++) {
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            s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
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            if (s->picture_structure == PICT_BOTTOM_FIELD)
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                s->current_picture.f->data[i] +=
                    s->current_picture_ptr->f->linesize[i];
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        }
    }

    if (avctx->hwaccel) {
1761 1762
        if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
            return ret;
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    }

    return 0;
}

#define DECODE_SLICE_ERROR -1
#define DECODE_SLICE_OK     0

/**
 * Decode a slice.
 * MpegEncContext.mb_y must be set to the MB row from the startcode.
 * @return DECODE_SLICE_ERROR if the slice is damaged,
 *         DECODE_SLICE_OK if this slice is OK
 */
static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
                             const uint8_t **buf, int buf_size)
{
    AVCodecContext *avctx = s->avctx;
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    const int lowres      = s->avctx->lowres;
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    const int field_pic   = s->picture_structure != PICT_FRAME;
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    int ret;
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    s->resync_mb_x =
    s->resync_mb_y = -1;

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    av_assert0(mb_y < s->mb_height);
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    init_get_bits(&s->gb, *buf, buf_size * 8);
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    if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
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        skip_bits(&s->gb, 3);
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    ff_mpeg1_clean_buffers(s);
    s->interlaced_dct = 0;

    s->qscale = get_qscale(s);

    if (s->qscale == 0) {
        av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1801
        return AVERROR_INVALIDDATA;
1802 1803 1804
    }

    /* extra slice info */
1805 1806
    if (skip_1stop_8data_bits(&s->gb) < 0)
        return AVERROR_INVALIDDATA;
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    s->mb_x = 0;

    if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
        skip_bits1(&s->gb);
    } else {
        while (get_bits_left(&s->gb) > 0) {
            int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
                                MBINCR_VLC_BITS, 2);
            if (code < 0) {
                av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1818
                return AVERROR_INVALIDDATA;
1819 1820
            }
            if (code >= 33) {
1821
                if (code == 33)
1822 1823 1824 1825 1826 1827 1828 1829 1830
                    s->mb_x += 33;
                /* otherwise, stuffing, nothing to do */
            } else {
                s->mb_x += code;
                break;
            }
        }
    }

1831
    if (s->mb_x >= (unsigned) s->mb_width) {
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        av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1833
        return AVERROR_INVALIDDATA;
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    }

1836
    if (avctx->hwaccel && avctx->hwaccel->decode_slice) {
1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855
        const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
        int start_code = -1;
        buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
        if (buf_end < *buf + buf_size)
            buf_end -= 4;
        s->mb_y = mb_y;
        if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
            return DECODE_SLICE_ERROR;
        *buf = buf_end;
        return DECODE_SLICE_OK;
    }

    s->resync_mb_x = s->mb_x;
    s->resync_mb_y = s->mb_y = mb_y;
    s->mb_skip_run = 0;
    ff_init_block_index(s);

    if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
        if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871
            av_log(s->avctx, AV_LOG_DEBUG,
                   "qp:%d fc:%2d%2d%2d%2d %s %s %s %s %s dc:%d pstruct:%d fdct:%d cmv:%d qtype:%d ivlc:%d rff:%d %s\n",
                   s->qscale,
                   s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
                   s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
                   s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
                   (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
                   (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
                   s->progressive_sequence ? "ps"  : "",
                   s->progressive_frame    ? "pf"  : "",
                   s->alternate_scan       ? "alt" : "",
                   s->top_field_first      ? "top" : "",
                   s->intra_dc_precision, s->picture_structure,
                   s->frame_pred_frame_dct, s->concealment_motion_vectors,
                   s->q_scale_type, s->intra_vlc_format,
                   s->repeat_first_field, s->chroma_420_type ? "420" : "");
1872 1873 1874 1875 1876
        }
    }

    for (;;) {
        // If 1, we memcpy blocks in xvmcvideo.
1877
        if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1878 1879
            ff_xvmc_init_block(s); // set s->block

1880 1881
        if ((ret = mpeg_decode_mb(s, s->block)) < 0)
            return ret;
1882

1883 1884
        // Note motion_val is normally NULL unless we want to extract the MVs.
        if (s->current_picture.motion_val[0] && !s->encoding) {
1885 1886 1887 1888 1889 1890 1891
            const int wrap = s->b8_stride;
            int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
            int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
            int motion_x, motion_y, dir, i;

            for (i = 0; i < 2; i++) {
                for (dir = 0; dir < 2; dir++) {
1892 1893
                    if (s->mb_intra ||
                        (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1894
                        motion_x = motion_y = 0;
1895 1896
                    } else if (s->mv_type == MV_TYPE_16X16 ||
                               (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1897 1898
                        motion_x = s->mv[dir][0][0];
                        motion_y = s->mv[dir][0][1];
1899
                    } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1900 1901 1902 1903
                        motion_x = s->mv[dir][i][0];
                        motion_y = s->mv[dir][i][1];
                    }

1904 1905
                    s->current_picture.motion_val[dir][xy][0]     = motion_x;
                    s->current_picture.motion_val[dir][xy][1]     = motion_y;
1906 1907
                    s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
                    s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1908
                    s->current_picture.ref_index [dir][b8_xy]     =
1909
                    s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1910 1911
                    av_assert2(s->field_select[dir][i] == 0 ||
                               s->field_select[dir][i] == 1);
1912
                }
1913 1914
                xy    += wrap;
                b8_xy += 2;
1915 1916 1917
            }
        }

1918 1919 1920
        s->dest[0] += 16 >> lowres;
        s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
        s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1921

1922
        ff_mpv_decode_mb(s, s->block);
1923 1924

        if (++s->mb_x >= s->mb_width) {
1925
            const int mb_size = 16 >> s->avctx->lowres;
1926

1927
            ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1928
            ff_mpv_report_decode_progress(s);
1929

1930
            s->mb_x  = 0;
1931 1932 1933 1934
            s->mb_y += 1 << field_pic;

            if (s->mb_y >= s->mb_height) {
                int left   = get_bits_left(&s->gb);
1935 1936 1937 1938 1939 1940 1941
                int is_d10 = s->chroma_format == 2 &&
                             s->pict_type == AV_PICTURE_TYPE_I &&
                             avctx->profile == 0 && avctx->level == 5 &&
                             s->intra_dc_precision == 2 &&
                             s->q_scale_type == 1 && s->alternate_scan == 0 &&
                             s->progressive_frame == 0
                             /* vbv_delay == 0xBBB || 0xE10 */;
1942

1943 1944 1945 1946 1947 1948 1949 1950 1951
                if (left >= 32 && !is_d10) {
                    GetBitContext gb = s->gb;
                    align_get_bits(&gb);
                    if (show_bits(&gb, 24) == 0x060E2B) {
                        av_log(avctx, AV_LOG_DEBUG, "Invalid MXF data found in video stream\n");
                        is_d10 = 1;
                    }
                }

1952 1953
                if (left < 0 ||
                    (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1954
                    ((avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE)) && left > 8)) {
1955 1956
                    av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
                           left, show_bits(&s->gb, FFMIN(left, 23)));
1957
                    return AVERROR_INVALIDDATA;
1958 1959 1960
                } else
                    goto eos;
            }
1961
            // There are some files out there which are missing the last slice
1962
            // in cases where the slice is completely outside the visible
1963 1964
            // area, we detect this here instead of running into the end expecting
            // more data
1965 1966 1967 1968 1969 1970 1971
            if (s->mb_y >= ((s->height + 15) >> 4) &&
                !s->progressive_sequence &&
                get_bits_left(&s->gb) <= 8 &&
                get_bits_left(&s->gb) >= 0 &&
                s->mb_skip_run == -1 &&
                show_bits(&s->gb, 8) == 0)
                goto eos;
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984

            ff_init_block_index(s);
        }

        /* skip mb handling */
        if (s->mb_skip_run == -1) {
            /* read increment again */
            s->mb_skip_run = 0;
            for (;;) {
                int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
                                    MBINCR_VLC_BITS, 2);
                if (code < 0) {
                    av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1985
                    return AVERROR_INVALIDDATA;
1986 1987 1988 1989 1990 1991 1992
                }
                if (code >= 33) {
                    if (code == 33) {
                        s->mb_skip_run += 33;
                    } else if (code == 35) {
                        if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
                            av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1993
                            return AVERROR_INVALIDDATA;
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
                        }
                        goto eos; /* end of slice */
                    }
                    /* otherwise, stuffing, nothing to do */
                } else {
                    s->mb_skip_run += code;
                    break;
                }
            }
            if (s->mb_skip_run) {
                int i;
                if (s->pict_type == AV_PICTURE_TYPE_I) {
2006 2007
                    av_log(s->avctx, AV_LOG_ERROR,
                           "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
2008
                    return AVERROR_INVALIDDATA;
2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036
                }

                /* skip mb */
                s->mb_intra = 0;
                for (i = 0; i < 12; i++)
                    s->block_last_index[i] = -1;
                if (s->picture_structure == PICT_FRAME)
                    s->mv_type = MV_TYPE_16X16;
                else
                    s->mv_type = MV_TYPE_FIELD;
                if (s->pict_type == AV_PICTURE_TYPE_P) {
                    /* if P type, zero motion vector is implied */
                    s->mv_dir             = MV_DIR_FORWARD;
                    s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
                    s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
                    s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
                    s->field_select[0][0] = (s->picture_structure - 1) & 1;
                } else {
                    /* if B type, reuse previous vectors and directions */
                    s->mv[0][0][0] = s->last_mv[0][0][0];
                    s->mv[0][0][1] = s->last_mv[0][0][1];
                    s->mv[1][0][0] = s->last_mv[1][0][0];
                    s->mv[1][0][1] = s->last_mv[1][0][1];
                }
            }
        }
    }
eos: // end of slice
2037 2038
    if (get_bits_left(&s->gb) < 0) {
        av_log(s, AV_LOG_ERROR, "overread %d\n", -get_bits_left(&s->gb));
2039
        return AVERROR_INVALIDDATA;
2040
    }
2041
    *buf += (get_bits_count(&s->gb) - 1) / 8;
2042
    ff_dlog(s, "Slice start:%d %d  end:%d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
2043 2044 2045 2046 2047
    return 0;
}

static int slice_decode_thread(AVCodecContext *c, void *arg)
{
2048
    MpegEncContext *s   = *(void **) arg;
2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060
    const uint8_t *buf  = s->gb.buffer;
    int mb_y            = s->start_mb_y;
    const int field_pic = s->picture_structure != PICT_FRAME;

    s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;

    for (;;) {
        uint32_t start_code;
        int ret;

        ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
        emms_c();
2061
        ff_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
2062 2063 2064 2065 2066 2067
                ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
                s->start_mb_y, s->end_mb_y, s->er.error_count);
        if (ret < 0) {
            if (c->err_recognition & AV_EF_EXPLODE)
                return ret;
            if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
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                ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
                                s->mb_x, s->mb_y,
                                ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2071
        } else {
2072 2073 2074
            ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
                            s->mb_x - 1, s->mb_y,
                            ER_AC_END | ER_DC_END | ER_MV_END);
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        }

        if (s->mb_y == s->end_mb_y)
            return 0;

        start_code = -1;
2081
        buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
2082 2083
        mb_y       = start_code - SLICE_MIN_START_CODE;
        if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
2084 2085
            mb_y += (*buf&0xE0)<<2;
        mb_y <<= field_pic;
2086 2087 2088
        if (s->picture_structure == PICT_BOTTOM_FIELD)
            mb_y++;
        if (mb_y < 0 || mb_y >= s->end_mb_y)
2089
            return AVERROR_INVALIDDATA;
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    }
}

/**
 * Handle slice ends.
 * @return 1 if it seems to be the last slice
 */
static int slice_end(AVCodecContext *avctx, AVFrame *pict)
{
2099
    Mpeg1Context *s1  = avctx->priv_data;
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    MpegEncContext *s = &s1->mpeg_enc_ctx;

    if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
        return 0;

    if (s->avctx->hwaccel) {
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        int ret = s->avctx->hwaccel->end_frame(s->avctx);
        if (ret < 0) {
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            av_log(avctx, AV_LOG_ERROR,
                   "hardware accelerator failed to decode picture\n");
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            return ret;
        }
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    }

    /* end of slice reached */
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    if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field && !s1->first_slice) {
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        /* end of image */

        ff_er_frame_end(&s->er);

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        ff_mpv_frame_end(s);
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        if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2123
            int ret = av_frame_ref(pict, s->current_picture_ptr->f);
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            if (ret < 0)
                return ret;
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            ff_print_debug_info(s, s->current_picture_ptr, pict);
            ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG2);
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        } else {
            if (avctx->active_thread_type & FF_THREAD_FRAME)
                s->picture_number++;
            /* latency of 1 frame for I- and P-frames */
            /* XXX: use another variable than picture_number */
2133
            if (s->last_picture_ptr) {
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                int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2135 2136
                if (ret < 0)
                    return ret;
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                ff_print_debug_info(s, s->last_picture_ptr, pict);
                ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG2);
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            }
        }

        return 1;
    } else {
        return 0;
    }
}

static int mpeg1_decode_sequence(AVCodecContext *avctx,
                                 const uint8_t *buf, int buf_size)
{
2151
    Mpeg1Context *s1  = avctx->priv_data;
2152 2153 2154 2155
    MpegEncContext *s = &s1->mpeg_enc_ctx;
    int width, height;
    int i, v, j;

2156
    init_get_bits(&s->gb, buf, buf_size * 8);
2157 2158 2159 2160

    width  = get_bits(&s->gb, 12);
    height = get_bits(&s->gb, 12);
    if (width == 0 || height == 0) {
2161 2162
        av_log(avctx, AV_LOG_WARNING,
               "Invalid horizontal or vertical size value.\n");
2163
        if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
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            return AVERROR_INVALIDDATA;
    }
    s->aspect_ratio_info = get_bits(&s->gb, 4);
    if (s->aspect_ratio_info == 0) {
        av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
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        if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2170
            return AVERROR_INVALIDDATA;
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    }
    s->frame_rate_index = get_bits(&s->gb, 4);
2173
    if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
2174 2175
        av_log(avctx, AV_LOG_WARNING,
               "frame_rate_index %d is invalid\n", s->frame_rate_index);
2176
        s->frame_rate_index = 1;
2177
    }
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    s->bit_rate = get_bits(&s->gb, 18) * 400LL;
2179
    if (check_marker(&s->gb, "in sequence header") == 0) {
2180
        return AVERROR_INVALIDDATA;
2181
    }
2182 2183 2184 2185 2186 2187 2188 2189 2190

    s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
    skip_bits(&s->gb, 1);

    /* get matrix */
    if (get_bits1(&s->gb)) {
        load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
    } else {
        for (i = 0; i < 64; i++) {
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            j = s->idsp.idct_permutation[i];
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            v = ff_mpeg1_default_intra_matrix[i];
            s->intra_matrix[j]        = v;
            s->chroma_intra_matrix[j] = v;
        }
    }
    if (get_bits1(&s->gb)) {
        load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
    } else {
        for (i = 0; i < 64; i++) {
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            int j = s->idsp.idct_permutation[i];
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            v = ff_mpeg1_default_non_intra_matrix[i];
            s->inter_matrix[j]        = v;
            s->chroma_inter_matrix[j] = v;
        }
    }

    if (show_bits(&s->gb, 23) != 0) {
        av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2210
        return AVERROR_INVALIDDATA;
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    }

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    s->width  = width;
    s->height = height;

2216
    /* We set MPEG-2 parameters so that it emulates MPEG-1. */
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    s->progressive_sequence = 1;
    s->progressive_frame    = 1;
    s->picture_structure    = PICT_FRAME;
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    s->first_field          = 0;
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    s->frame_pred_frame_dct = 1;
    s->chroma_format        = 1;
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    s->codec_id             =
    s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
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    s->out_format           = FMT_MPEG1;
    s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2227
    if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
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        s->low_delay = 1;

    if (s->avctx->debug & FF_DEBUG_PICT_INFO)
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        av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%"PRId64", aspect_ratio_info: %d \n",
2232
               s->avctx->rc_buffer_size, s->bit_rate, s->aspect_ratio_info);
2233 2234 2235 2236 2237 2238

    return 0;
}

static int vcr2_init_sequence(AVCodecContext *avctx)
{
2239
    Mpeg1Context *s1  = avctx->priv_data;
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    MpegEncContext *s = &s1->mpeg_enc_ctx;
2241
    int i, v, ret;
2242 2243 2244 2245

    /* start new MPEG-1 context decoding */
    s->out_format = FMT_MPEG1;
    if (s1->mpeg_enc_ctx_allocated) {
2246
        ff_mpv_common_end(s);
2247
        s1->mpeg_enc_ctx_allocated = 0;
2248
    }
2249 2250
    s->width            = avctx->coded_width;
    s->height           = avctx->coded_height;
2251
    avctx->has_b_frames = 0; // true?
2252
    s->low_delay        = 1;
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    avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2255
    setup_hwaccel_for_pixfmt(avctx);
2256

2257
    ff_mpv_idct_init(s);
2258 2259
    if ((ret = ff_mpv_common_init(s)) < 0)
        return ret;
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    s1->mpeg_enc_ctx_allocated = 1;

    for (i = 0; i < 64; i++) {
2263
        int j = s->idsp.idct_permutation[i];
2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275
        v = ff_mpeg1_default_intra_matrix[i];
        s->intra_matrix[j]        = v;
        s->chroma_intra_matrix[j] = v;

        v = ff_mpeg1_default_non_intra_matrix[i];
        s->inter_matrix[j]        = v;
        s->chroma_inter_matrix[j] = v;
    }

    s->progressive_sequence  = 1;
    s->progressive_frame     = 1;
    s->picture_structure     = PICT_FRAME;
2276
    s->first_field           = 0;
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    s->frame_pred_frame_dct  = 1;
    s->chroma_format         = 1;
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    if (s->codec_tag == AV_RL32("BW10")) {
        s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
    } else {
        s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
        s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
    }
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    s1->save_width           = s->width;
    s1->save_height          = s->height;
    s1->save_progressive_seq = s->progressive_sequence;
    return 0;
}

2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303
static int mpeg_decode_a53_cc(AVCodecContext *avctx,
                              const uint8_t *p, int buf_size)
{
    Mpeg1Context *s1 = avctx->priv_data;

    if (buf_size >= 6 &&
        p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
        p[4] == 3 && (p[5] & 0x40)) {
        /* extract A53 Part 4 CC data */
        int cc_count = p[5] & 0x1f;
        if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
            av_freep(&s1->a53_caption);
            s1->a53_caption_size = cc_count * 3;
2304 2305
            s1->a53_caption      = av_malloc(s1->a53_caption_size);
            if (s1->a53_caption)
2306 2307 2308 2309
                memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
        }
        return 1;
    } else if (buf_size >= 11 &&
2310
               p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321
        /* extract DVD CC data */
        int cc_count = 0;
        int i;
        // There is a caption count field in the data, but it is often
        // incorect.  So count the number of captions present.
        for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
            cc_count++;
        // Transform the DVD format into A53 Part 4 format
        if (cc_count > 0) {
            av_freep(&s1->a53_caption);
            s1->a53_caption_size = cc_count * 6;
2322
            s1->a53_caption      = av_malloc(s1->a53_caption_size);
2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343
            if (s1->a53_caption) {
                uint8_t field1 = !!(p[4] & 0x80);
                uint8_t *cap = s1->a53_caption;
                p += 5;
                for (i = 0; i < cc_count; i++) {
                    cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
                    cap[1] = p[1];
                    cap[2] = p[2];
                    cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
                    cap[4] = p[4];
                    cap[5] = p[5];
                    cap += 6;
                    p += 6;
                }
            }
        }
        return 1;
    }
    return 0;
}

2344 2345 2346
static void mpeg_decode_user_data(AVCodecContext *avctx,
                                  const uint8_t *p, int buf_size)
{
2347
    Mpeg1Context *s = avctx->priv_data;
2348
    const uint8_t *buf_end = p + buf_size;
2349
    Mpeg1Context *s1 = avctx->priv_data;
2350

2351 2352 2353 2354 2355 2356 2357 2358
#if 0
    int i;
    for(i=0; !(!p[i-2] && !p[i-1] && p[i]==1) && i<buf_size; i++){
        av_log(avctx, AV_LOG_ERROR, "%c", p[i]);
    }
    av_log(avctx, AV_LOG_ERROR, "\n");
#endif

2359
    if (buf_size > 29){
2360 2361
        int i;
        for(i=0; i<20; i++)
2362
            if (!memcmp(p+i, "\0TMPGEXS\0", 9)){
2363 2364 2365
                s->tmpgexs= 1;
            }
    }
2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377
    /* we parse the DTG active format information */
    if (buf_end - p >= 5 &&
        p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
        int flags = p[4];
        p += 5;
        if (flags & 0x80) {
            /* skip event id */
            p += 2;
        }
        if (flags & 0x40) {
            if (buf_end - p < 1)
                return;
2378
#if FF_API_AFD
2379
FF_DISABLE_DEPRECATION_WARNINGS
2380
            avctx->dtg_active_format = p[0] & 0x0f;
2381
FF_ENABLE_DEPRECATION_WARNINGS
2382
#endif /* FF_API_AFD */
2383
            s1->has_afd = 1;
2384
            s1->afd     = p[0] & 0x0f;
2385
        }
2386 2387 2388 2389 2390 2391 2392 2393 2394 2395
    } else if (buf_end - p >= 6 &&
               p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
               p[4] == 0x03) { // S3D_video_format_length
        // the 0x7F mask ignores the reserved_bit value
        const uint8_t S3D_video_format_type = p[5] & 0x7F;

        if (S3D_video_format_type == 0x03 ||
            S3D_video_format_type == 0x04 ||
            S3D_video_format_type == 0x08 ||
            S3D_video_format_type == 0x23) {
2396

2397
            s1->has_stereo3d = 1;
2398 2399 2400

            switch (S3D_video_format_type) {
            case 0x03:
2401
                s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2402 2403
                break;
            case 0x04:
2404
                s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2405 2406
                break;
            case 0x08:
2407
                s1->stereo3d.type = AV_STEREO3D_2D;
2408 2409
                break;
            case 0x23:
2410
                s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2411 2412 2413
                break;
            }
        }
2414 2415
    } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
        return;
2416 2417 2418 2419 2420 2421 2422 2423 2424
    }
}

static void mpeg_decode_gop(AVCodecContext *avctx,
                            const uint8_t *buf, int buf_size)
{
    Mpeg1Context *s1  = avctx->priv_data;
    MpegEncContext *s = &s1->mpeg_enc_ctx;
    int broken_link;
2425
    int64_t tc;
2426

2427
    init_get_bits(&s->gb, buf, buf_size * 8);
2428

2429
    tc = avctx->timecode_frame_start = get_bits(&s->gb, 25);
2430

2431
    s->closed_gop = get_bits1(&s->gb);
2432 2433 2434
    /* broken_link indicate that after editing the
     * reference frames of the first B-Frames after GOP I-Frame
     * are missing (open gop) */
2435 2436
    broken_link = get_bits1(&s->gb);

2437 2438 2439 2440 2441 2442 2443
    if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
        char tcbuf[AV_TIMECODE_STR_SIZE];
        av_timecode_make_mpeg_tc_string(tcbuf, tc);
        av_log(s->avctx, AV_LOG_DEBUG,
               "GOP (%s) closed_gop=%d broken_link=%d\n",
               tcbuf, s->closed_gop, broken_link);
    }
2444 2445
}

2446 2447
static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
                         int *got_output, const uint8_t *buf, int buf_size)
2448 2449 2450 2451 2452 2453
{
    Mpeg1Context *s = avctx->priv_data;
    MpegEncContext *s2 = &s->mpeg_enc_ctx;
    const uint8_t *buf_ptr = buf;
    const uint8_t *buf_end = buf + buf_size;
    int ret, input_size;
2454
    int last_code = 0, skip_frame = 0;
2455
    int picture_start_code_seen = 0;
2456 2457 2458 2459 2460 2461

    for (;;) {
        /* find next start code */
        uint32_t start_code = -1;
        buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
        if (start_code > 0x1ff) {
2462
            if (!skip_frame) {
2463 2464
                if (HAVE_THREADS &&
                    (avctx->active_thread_type & FF_THREAD_SLICE) &&
2465
                    !avctx->hwaccel) {
2466
                    int i;
2467
                    av_assert0(avctx->thread_count > 1);
2468

2469 2470 2471
                    avctx->execute(avctx, slice_decode_thread,
                                   &s2->thread_context[0], NULL,
                                   s->slice_count, sizeof(void *));
2472 2473 2474 2475
                    for (i = 0; i < s->slice_count; i++)
                        s2->er.error_count += s2->thread_context[i]->er.error_count;
                }

2476
#if FF_API_VDPAU
2477 2478 2479
                if ((CONFIG_MPEG_VDPAU_DECODER || CONFIG_MPEG1_VDPAU_DECODER)
                    && uses_vdpau(avctx))
                    ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2480
#endif
2481

2482 2483 2484 2485
                ret = slice_end(avctx, picture);
                if (ret < 0)
                    return ret;
                else if (ret) {
2486 2487
                    // FIXME: merge with the stuff in mpeg_decode_slice
                    if (s2->last_picture_ptr || s2->low_delay)
2488 2489 2490 2491
                        *got_output = 1;
                }
            }
            s2->pict_type = 0;
2492 2493 2494 2495

            if (avctx->err_recognition & AV_EF_EXPLODE && s2->er.error_count)
                return AVERROR_INVALIDDATA;

2496 2497 2498 2499 2500
            return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
        }

        input_size = buf_end - buf_ptr;

2501
        if (avctx->debug & FF_DEBUG_STARTCODE)
2502
            av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %"PTRDIFF_SPECIFIER" left %d\n",
2503
                   start_code, buf_ptr - buf, input_size);
2504 2505 2506 2507 2508 2509

        /* prepare data for next start code */
        switch (start_code) {
        case SEQ_START_CODE:
            if (last_code == 0) {
                mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2510 2511
                if (buf != avctx->extradata)
                    s->sync = 1;
2512
            } else {
2513 2514
                av_log(avctx, AV_LOG_ERROR,
                       "ignoring SEQ_START_CODE after %X\n", last_code);
2515 2516 2517 2518 2519 2520
                if (avctx->err_recognition & AV_EF_EXPLODE)
                    return AVERROR_INVALIDDATA;
            }
            break;

        case PICTURE_START_CODE:
2521 2522 2523 2524 2525 2526 2527 2528
            if (picture_start_code_seen && s2->picture_structure == PICT_FRAME) {
               /* If it's a frame picture, there can't be more than one picture header.
                  Yet, it does happen and we need to handle it. */
               av_log(avctx, AV_LOG_WARNING, "ignoring extra picture following a frame-picture\n");
               break;
            }
            picture_start_code_seen = 1;

2529 2530 2531 2532 2533 2534
            if (s2->width <= 0 || s2->height <= 0) {
                av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
                       s2->width, s2->height);
                return AVERROR_INVALIDDATA;
            }

2535
            if (s->tmpgexs){
2536 2537 2538
                s2->intra_dc_precision= 3;
                s2->intra_matrix[0]= 1;
            }
2539 2540
            if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
                !avctx->hwaccel && s->slice_count) {
2541 2542 2543 2544
                int i;

                avctx->execute(avctx, slice_decode_thread,
                               s2->thread_context, NULL,
2545
                               s->slice_count, sizeof(void *));
2546 2547 2548 2549 2550 2551 2552
                for (i = 0; i < s->slice_count; i++)
                    s2->er.error_count += s2->thread_context[i]->er.error_count;
                s->slice_count = 0;
            }
            if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
                ret = mpeg_decode_postinit(avctx);
                if (ret < 0) {
2553 2554
                    av_log(avctx, AV_LOG_ERROR,
                           "mpeg_decode_postinit() failure\n");
2555 2556 2557
                    return ret;
                }

2558
                /* We have a complete image: we try to decompress it. */
2559 2560
                if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
                    s2->pict_type = 0;
2561
                s->first_slice = 1;
2562
                last_code      = PICTURE_START_CODE;
2563
            } else {
2564 2565
                av_log(avctx, AV_LOG_ERROR,
                       "ignoring pic after %X\n", last_code);
2566 2567 2568 2569 2570
                if (avctx->err_recognition & AV_EF_EXPLODE)
                    return AVERROR_INVALIDDATA;
            }
            break;
        case EXT_START_CODE:
2571
            init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2572 2573 2574 2575

            switch (get_bits(&s2->gb, 4)) {
            case 0x1:
                if (last_code == 0) {
2576
                    mpeg_decode_sequence_extension(s);
2577
                } else {
2578 2579
                    av_log(avctx, AV_LOG_ERROR,
                           "ignoring seq ext after %X\n", last_code);
2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596
                    if (avctx->err_recognition & AV_EF_EXPLODE)
                        return AVERROR_INVALIDDATA;
                }
                break;
            case 0x2:
                mpeg_decode_sequence_display_extension(s);
                break;
            case 0x3:
                mpeg_decode_quant_matrix_extension(s2);
                break;
            case 0x7:
                mpeg_decode_picture_display_extension(s);
                break;
            case 0x8:
                if (last_code == PICTURE_START_CODE) {
                    mpeg_decode_picture_coding_extension(s);
                } else {
2597 2598
                    av_log(avctx, AV_LOG_ERROR,
                           "ignoring pic cod ext after %X\n", last_code);
2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609
                    if (avctx->err_recognition & AV_EF_EXPLODE)
                        return AVERROR_INVALIDDATA;
                }
                break;
            }
            break;
        case USER_START_CODE:
            mpeg_decode_user_data(avctx, buf_ptr, input_size);
            break;
        case GOP_START_CODE:
            if (last_code == 0) {
2610
                s2->first_field = 0;
2611
                mpeg_decode_gop(avctx, buf_ptr, input_size);
2612
                s->sync = 1;
2613
            } else {
2614 2615
                av_log(avctx, AV_LOG_ERROR,
                       "ignoring GOP_START_CODE after %X\n", last_code);
2616 2617 2618 2619 2620
                if (avctx->err_recognition & AV_EF_EXPLODE)
                    return AVERROR_INVALIDDATA;
            }
            break;
        default:
2621 2622 2623 2624
            if (start_code >= SLICE_MIN_START_CODE &&
                start_code <= SLICE_MAX_START_CODE && last_code == PICTURE_START_CODE) {
                if (s2->progressive_sequence && !s2->progressive_frame) {
                    s2->progressive_frame = 1;
2625 2626
                    av_log(s2->avctx, AV_LOG_ERROR,
                           "interlaced frame in progressive sequence, ignoring\n");
2627 2628
                }

2629 2630 2631 2632 2633
                if (s2->picture_structure == 0 ||
                    (s2->progressive_frame && s2->picture_structure != PICT_FRAME)) {
                    av_log(s2->avctx, AV_LOG_ERROR,
                           "picture_structure %d invalid, ignoring\n",
                           s2->picture_structure);
2634 2635 2636
                    s2->picture_structure = PICT_FRAME;
                }

2637
                if (s2->progressive_sequence && !s2->frame_pred_frame_dct)
2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648
                    av_log(s2->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");

                if (s2->picture_structure == PICT_FRAME) {
                    s2->first_field = 0;
                    s2->v_edge_pos  = 16 * s2->mb_height;
                } else {
                    s2->first_field ^= 1;
                    s2->v_edge_pos   = 8 * s2->mb_height;
                    memset(s2->mbskip_table, 0, s2->mb_stride * s2->mb_height);
                }
            }
2649 2650 2651
            if (start_code >= SLICE_MIN_START_CODE &&
                start_code <= SLICE_MAX_START_CODE && last_code != 0) {
                const int field_pic = s2->picture_structure != PICT_FRAME;
2652
                int mb_y = start_code - SLICE_MIN_START_CODE;
2653
                last_code = SLICE_MIN_START_CODE;
2654
                if (s2->codec_id != AV_CODEC_ID_MPEG1VIDEO && s2->mb_height > 2800/16)
2655
                    mb_y += (*buf_ptr&0xE0)<<2;
2656

2657
                mb_y <<= field_pic;
2658 2659 2660
                if (s2->picture_structure == PICT_BOTTOM_FIELD)
                    mb_y++;

2661 2662 2663 2664 2665
                if (buf_end - buf_ptr < 2) {
                    av_log(s2->avctx, AV_LOG_ERROR, "slice too small\n");
                    return AVERROR_INVALIDDATA;
                }

2666
                if (mb_y >= s2->mb_height) {
2667 2668
                    av_log(s2->avctx, AV_LOG_ERROR,
                           "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2669
                    return AVERROR_INVALIDDATA;
2670 2671
                }

2672
                if (!s2->last_picture_ptr) {
2673 2674
                    /* Skip B-frames if we do not have reference frames and
                     * GOP is not closed. */
2675
                    if (s2->pict_type == AV_PICTURE_TYPE_B) {
2676
                        if (!s2->closed_gop) {
2677
                            skip_frame = 1;
2678
                            break;
2679
                        }
2680 2681
                    }
                }
2682
                if (s2->pict_type == AV_PICTURE_TYPE_I || (s2->avctx->flags2 & AV_CODEC_FLAG2_SHOW_ALL))
2683
                    s->sync = 1;
2684
                if (!s2->next_picture_ptr) {
2685 2686
                    /* Skip P-frames if we do not have a reference frame or
                     * we have an invalid header. */
2687 2688 2689 2690
                    if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
                        skip_frame = 1;
                        break;
                    }
2691
                }
2692 2693 2694 2695 2696
                if ((avctx->skip_frame >= AVDISCARD_NONREF &&
                     s2->pict_type == AV_PICTURE_TYPE_B) ||
                    (avctx->skip_frame >= AVDISCARD_NONKEY &&
                     s2->pict_type != AV_PICTURE_TYPE_I) ||
                    avctx->skip_frame >= AVDISCARD_ALL) {
2697
                    skip_frame = 1;
2698
                    break;
2699
                }
2700 2701 2702 2703 2704

                if (!s->mpeg_enc_ctx_allocated)
                    break;

                if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2705 2706
                    if (mb_y < avctx->skip_top ||
                        mb_y >= s2->mb_height - avctx->skip_bottom)
2707 2708 2709 2710 2711 2712 2713 2714 2715 2716
                        break;
                }

                if (!s2->pict_type) {
                    av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
                    if (avctx->err_recognition & AV_EF_EXPLODE)
                        return AVERROR_INVALIDDATA;
                    break;
                }

2717
                if (s->first_slice) {
2718
                    skip_frame     = 0;
2719
                    s->first_slice = 0;
2720 2721
                    if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
                        return ret;
2722 2723
                }
                if (!s2->current_picture_ptr) {
2724 2725
                    av_log(avctx, AV_LOG_ERROR,
                           "current_picture not initialized\n");
2726 2727 2728
                    return AVERROR_INVALIDDATA;
                }

2729
#if FF_API_VDPAU
2730 2731 2732 2733
                if (uses_vdpau(avctx)) {
                    s->slice_count++;
                    break;
                }
2734
#endif
2735

2736 2737
                if (HAVE_THREADS &&
                    (avctx->active_thread_type & FF_THREAD_SLICE) &&
2738
                    !avctx->hwaccel) {
2739 2740 2741
                    int threshold = (s2->mb_height * s->slice_count +
                                     s2->slice_context_count / 2) /
                                    s2->slice_context_count;
2742
                    av_assert0(avctx->thread_count > 1);
2743 2744 2745 2746 2747 2748
                    if (threshold <= mb_y) {
                        MpegEncContext *thread_context = s2->thread_context[s->slice_count];

                        thread_context->start_mb_y = mb_y;
                        thread_context->end_mb_y   = s2->mb_height;
                        if (s->slice_count) {
2749 2750
                            s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
                            ret = ff_update_duplicate_context(thread_context, s2);
2751 2752 2753
                            if (ret < 0)
                                return ret;
                        }
2754
                        init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765
                        s->slice_count++;
                    }
                    buf_ptr += 2; // FIXME add minimum number of bytes per slice
                } else {
                    ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
                    emms_c();

                    if (ret < 0) {
                        if (avctx->err_recognition & AV_EF_EXPLODE)
                            return ret;
                        if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2766 2767 2768
                            ff_er_add_slice(&s2->er, s2->resync_mb_x,
                                            s2->resync_mb_y, s2->mb_x, s2->mb_y,
                                            ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2769
                    } else {
2770 2771 2772
                        ff_er_add_slice(&s2->er, s2->resync_mb_x,
                                        s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
                                        ER_AC_END | ER_DC_END | ER_MV_END);
2773 2774 2775 2776 2777 2778 2779 2780
                    }
                }
            }
            break;
        }
    }
}

2781 2782
static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
                             int *got_output, AVPacket *avpkt)
2783 2784
{
    const uint8_t *buf = avpkt->data;
2785
    int ret;
2786 2787 2788 2789 2790 2791 2792 2793
    int buf_size = avpkt->size;
    Mpeg1Context *s = avctx->priv_data;
    AVFrame *picture = data;
    MpegEncContext *s2 = &s->mpeg_enc_ctx;

    if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
        /* special case for last picture */
        if (s2->low_delay == 0 && s2->next_picture_ptr) {
2794
            int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2795 2796 2797 2798 2799 2800 2801 2802 2803 2804
            if (ret < 0)
                return ret;

            s2->next_picture_ptr = NULL;

            *got_output = 1;
        }
        return buf_size;
    }

2805
    if (s2->avctx->flags & AV_CODEC_FLAG_TRUNCATED) {
2806 2807
        int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
                                           buf_size, NULL);
2808

2809 2810
        if (ff_combine_frame(&s2->parse_context, next,
                             (const uint8_t **) &buf, &buf_size) < 0)
2811 2812 2813
            return buf_size;
    }

2814 2815 2816 2817
    s2->codec_tag = avpriv_toupper4(avctx->codec_tag);
    if (s->mpeg_enc_ctx_allocated == 0 && (   s2->codec_tag == AV_RL32("VCR2")
                                           || s2->codec_tag == AV_RL32("BW10")
                                          ))
2818 2819 2820 2821 2822
        vcr2_init_sequence(avctx);

    s->slice_count = 0;

    if (avctx->extradata && !s->extradata_decoded) {
2823 2824 2825
        ret = decode_chunks(avctx, picture, got_output,
                            avctx->extradata, avctx->extradata_size);
        if (*got_output) {
2826 2827 2828
            av_log(avctx, AV_LOG_ERROR, "picture in extradata\n");
            *got_output = 0;
        }
2829
        s->extradata_decoded = 1;
2830 2831
        if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) {
            s2->current_picture_ptr = NULL;
2832
            return ret;
2833
        }
2834 2835
    }

2836 2837 2838 2839 2840
    ret = decode_chunks(avctx, picture, got_output, buf, buf_size);
    if (ret<0 || *got_output)
        s2->current_picture_ptr = NULL;

    return ret;
2841 2842 2843 2844 2845 2846
}

static void flush(AVCodecContext *avctx)
{
    Mpeg1Context *s = avctx->priv_data;

2847
    s->sync       = 0;
2848 2849 2850 2851

    ff_mpeg_flush(avctx);
}

2852
static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2853 2854 2855 2856
{
    Mpeg1Context *s = avctx->priv_data;

    if (s->mpeg_enc_ctx_allocated)
2857
        ff_mpv_common_end(&s->mpeg_enc_ctx);
2858
    av_freep(&s->a53_caption);
2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870
    return 0;
}

static const AVProfile mpeg2_video_profiles[] = {
    { FF_PROFILE_MPEG2_422,          "4:2:2"              },
    { FF_PROFILE_MPEG2_HIGH,         "High"               },
    { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
    { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
    { FF_PROFILE_MPEG2_MAIN,         "Main"               },
    { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
    { FF_PROFILE_RESERVED,           "Reserved"           },
    { FF_PROFILE_RESERVED,           "Reserved"           },
2871
    { FF_PROFILE_UNKNOWN                                  },
2872 2873 2874 2875
};

AVCodec ff_mpeg1video_decoder = {
    .name                  = "mpeg1video",
2876
    .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2877 2878 2879 2880 2881 2882
    .type                  = AVMEDIA_TYPE_VIDEO,
    .id                    = AV_CODEC_ID_MPEG1VIDEO,
    .priv_data_size        = sizeof(Mpeg1Context),
    .init                  = mpeg_decode_init,
    .close                 = mpeg_decode_end,
    .decode                = mpeg_decode_frame,
2883 2884 2885
    .capabilities          = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
                             AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
                             AV_CODEC_CAP_SLICE_THREADS,
2886
    .flush                 = flush,
2887
    .max_lowres            = 3,
2888 2889 2890 2891 2892
    .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
};

AVCodec ff_mpeg2video_decoder = {
    .name           = "mpeg2video",
2893
    .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2894 2895 2896 2897 2898 2899
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_MPEG2VIDEO,
    .priv_data_size = sizeof(Mpeg1Context),
    .init           = mpeg_decode_init,
    .close          = mpeg_decode_end,
    .decode         = mpeg_decode_frame,
2900 2901 2902
    .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
                      AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
                      AV_CODEC_CAP_SLICE_THREADS,
2903
    .flush          = flush,
2904
    .max_lowres     = 3,
2905 2906 2907
    .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
};

2908 2909 2910
//legacy decoder
AVCodec ff_mpegvideo_decoder = {
    .name           = "mpegvideo",
2911
    .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2912 2913 2914 2915 2916 2917
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_MPEG2VIDEO,
    .priv_data_size = sizeof(Mpeg1Context),
    .init           = mpeg_decode_init,
    .close          = mpeg_decode_end,
    .decode         = mpeg_decode_frame,
2918
    .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS,
2919 2920 2921 2922
    .flush          = flush,
    .max_lowres     = 3,
};

2923
#if FF_API_XVMC
2924
#if CONFIG_MPEG_XVMC_DECODER
2925
FF_DISABLE_DEPRECATION_WARNINGS
2926 2927 2928 2929 2930 2931 2932
static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
{
    if (avctx->active_thread_type & FF_THREAD_SLICE)
        return -1;
    if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
        return -1;
    if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2933
        ff_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944
    }
    mpeg_decode_init(avctx);

    avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
    avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!

    return 0;
}

AVCodec ff_mpeg_xvmc_decoder = {
    .name           = "mpegvideo_xvmc",
2945
    .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2946 2947 2948 2949 2950 2951
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
    .priv_data_size = sizeof(Mpeg1Context),
    .init           = mpeg_mc_decode_init,
    .close          = mpeg_decode_end,
    .decode         = mpeg_decode_frame,
2952
    .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2953
                      AV_CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL |
2954
                      AV_CODEC_CAP_DELAY,
2955 2956
    .flush          = flush,
};
2957
FF_ENABLE_DEPRECATION_WARNINGS
2958
#endif
2959
#endif /* FF_API_XVMC */
2960

2961
#if CONFIG_MPEG_VDPAU_DECODER && FF_API_VDPAU
2962 2963
AVCodec ff_mpeg_vdpau_decoder = {
    .name           = "mpegvideo_vdpau",
2964
    .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2965 2966 2967 2968 2969 2970
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_MPEG2VIDEO,
    .priv_data_size = sizeof(Mpeg1Context),
    .init           = mpeg_decode_init,
    .close          = mpeg_decode_end,
    .decode         = mpeg_decode_frame,
2971 2972
    .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED |
                      AV_CODEC_CAP_HWACCEL_VDPAU | AV_CODEC_CAP_DELAY,
2973 2974 2975 2976
    .flush          = flush,
};
#endif

2977
#if CONFIG_MPEG1_VDPAU_DECODER && FF_API_VDPAU
2978 2979
AVCodec ff_mpeg1_vdpau_decoder = {
    .name           = "mpeg1video_vdpau",
2980
    .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2981 2982 2983 2984 2985 2986
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_MPEG1VIDEO,
    .priv_data_size = sizeof(Mpeg1Context),
    .init           = mpeg_decode_init,
    .close          = mpeg_decode_end,
    .decode         = mpeg_decode_frame,
2987 2988
    .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED |
                      AV_CODEC_CAP_HWACCEL_VDPAU | AV_CODEC_CAP_DELAY,
2989 2990 2991
    .flush          = flush,
};
#endif