mpeg4videodec.c 106 KB
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/*
 * MPEG4 decoder.
 * Copyright (c) 2000,2001 Fabrice Bellard
 * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * 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.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * 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
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

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#define UNCHECKED_BITSTREAM_READER 1

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#include "libavutil/opt.h"
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#include "error_resilience.h"
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#include "internal.h"
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#include "mpegvideo.h"
#include "mpeg4video.h"
#include "h263.h"
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#include "thread.h"
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/* The defines below define the number of bits that are read at once for
 * reading vlc values. Changing these may improve speed and data cache needs
 * be aware though that decreasing them may need the number of stages that is
 * passed to get_vlc* to be increased. */
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#define SPRITE_TRAJ_VLC_BITS 6
#define DC_VLC_BITS 9
#define MB_TYPE_B_VLC_BITS 4

static VLC dc_lum, dc_chrom;
static VLC sprite_trajectory;
static VLC mb_type_b_vlc;

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static const int mb_type_b_map[4] = {
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    MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
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    MB_TYPE_L0L1    | MB_TYPE_16x16,
    MB_TYPE_L1      | MB_TYPE_16x16,
    MB_TYPE_L0      | MB_TYPE_16x16,
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};

/**
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 * Predict the ac.
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 * @param n block index (0-3 are luma, 4-5 are chroma)
 * @param dir the ac prediction direction
 */
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void ff_mpeg4_pred_ac(MpegEncContext *s, int16_t *block, int n, int dir)
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{
    int i;
    int16_t *ac_val, *ac_val1;
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    int8_t *const qscale_table = s->current_picture.qscale_table;
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    /* find prediction */
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    ac_val  = s->ac_val[0][0] + s->block_index[n] * 16;
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    ac_val1 = ac_val;
    if (s->ac_pred) {
        if (dir == 0) {
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            const int xy = s->mb_x - 1 + s->mb_y * s->mb_stride;
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            /* left prediction */
            ac_val -= 16;

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            if (s->mb_x == 0 || s->qscale == qscale_table[xy] ||
                n == 1 || n == 3) {
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                /* same qscale */
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                for (i = 1; i < 8; i++)
                    block[s->dsp.idct_permutation[i << 3]] += ac_val[i];
            } else {
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                /* different qscale, we must rescale */
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                for (i = 1; i < 8; i++)
                    block[s->dsp.idct_permutation[i << 3]] += ROUNDED_DIV(ac_val[i] * qscale_table[xy], s->qscale);
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            }
        } else {
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            const int xy = s->mb_x + s->mb_y * s->mb_stride - s->mb_stride;
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            /* top prediction */
            ac_val -= 16 * s->block_wrap[n];

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            if (s->mb_y == 0 || s->qscale == qscale_table[xy] ||
                n == 2 || n == 3) {
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                /* same qscale */
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                for (i = 1; i < 8; i++)
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                    block[s->dsp.idct_permutation[i]] += ac_val[i + 8];
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            } else {
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                /* different qscale, we must rescale */
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                for (i = 1; i < 8; i++)
                    block[s->dsp.idct_permutation[i]] += ROUNDED_DIV(ac_val[i + 8] * qscale_table[xy], s->qscale);
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            }
        }
    }
    /* left copy */
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    for (i = 1; i < 8; i++)
        ac_val1[i] = block[s->dsp.idct_permutation[i << 3]];
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    /* top copy */
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    for (i = 1; i < 8; i++)
        ac_val1[8 + i] = block[s->dsp.idct_permutation[i]];
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}

/**
 * check if the next stuff is a resync marker or the end.
 * @return 0 if not
 */
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static inline int mpeg4_is_resync(Mpeg4DecContext *ctx)
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{
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    MpegEncContext *s = &ctx->m;
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    int bits_count = get_bits_count(&s->gb);
    int v          = show_bits(&s->gb, 16);
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    if (s->workaround_bugs & FF_BUG_NO_PADDING && !ctx->resync_marker)
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        return 0;

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    while (v <= 0xFF) {
        if (s->pict_type == AV_PICTURE_TYPE_B ||
            (v >> (8 - s->pict_type) != 1) || s->partitioned_frame)
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            break;
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        skip_bits(&s->gb, 8 + s->pict_type);
        bits_count += 8 + s->pict_type;
        v = show_bits(&s->gb, 16);
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    }

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    if (bits_count + 8 >= s->gb.size_in_bits) {
        v >>= 8;
        v  |= 0x7F >> (7 - (bits_count & 7));
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        if (v == 0x7F)
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            return s->mb_num;
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    } else {
        if (v == ff_mpeg4_resync_prefix[bits_count & 7]) {
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            int len, mb_num;
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            int mb_num_bits = av_log2(s->mb_num - 1) + 1;
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            GetBitContext gb = s->gb;
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            skip_bits(&s->gb, 1);
            align_get_bits(&s->gb);

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            for (len = 0; len < 32; len++)
                if (get_bits1(&s->gb))
                    break;
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            mb_num = get_bits(&s->gb, mb_num_bits);
            if (!mb_num || mb_num > s->mb_num || get_bits_count(&s->gb)+6 > s->gb.size_in_bits)
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                mb_num= -1;

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            s->gb = gb;
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            if (len >= ff_mpeg4_get_video_packet_prefix_length(s))
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                return mb_num;
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        }
    }
    return 0;
}

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static int mpeg4_decode_sprite_trajectory(Mpeg4DecContext *ctx, GetBitContext *gb)
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{
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    MpegEncContext *s = &ctx->m;
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    int a     = 2 << s->sprite_warping_accuracy;
    int rho   = 3  - s->sprite_warping_accuracy;
    int r     = 16 / a;
    int alpha = 0;
    int beta  = 0;
    int w     = s->width;
    int h     = s->height;
    int min_ab, i, w2, h2, w3, h3;
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    int sprite_ref[4][2];
    int virtual_ref[2][2];
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    // only true for rectangle shapes
    const int vop_ref[4][2] = { { 0, 0 },         { s->width, 0 },
                                { 0, s->height }, { s->width, s->height } };
    int d[4][2]             = { { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 } };
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    if (w <= 0 || h <= 0)
        return AVERROR_INVALIDDATA;
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    for (i = 0; i < ctx->num_sprite_warping_points; i++) {
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        int length;
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        int x = 0, y = 0;
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        length = get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
        if (length)
            x = get_xbits(gb, length);
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        if (!(ctx->divx_version == 500 && ctx->divx_build == 413))
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            skip_bits1(gb);     /* marker bit */

        length = get_vlc2(gb, sprite_trajectory.table, SPRITE_TRAJ_VLC_BITS, 3);
        if (length)
            y = get_xbits(gb, length);

        skip_bits1(gb);         /* marker bit */
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        ctx->sprite_traj[i][0] = d[i][0] = x;
        ctx->sprite_traj[i][1] = d[i][1] = y;
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    }
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    for (; i < 4; i++)
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        ctx->sprite_traj[i][0] = ctx->sprite_traj[i][1] = 0;
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    while ((1 << alpha) < w)
        alpha++;
    while ((1 << beta) < h)
        beta++;  /* typo in the mpeg4 std for the definition of w' and h' */
    w2 = 1 << alpha;
    h2 = 1 << beta;

    // Note, the 4th point isn't used for GMC
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    if (ctx->divx_version == 500 && ctx->divx_build == 413) {
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        sprite_ref[0][0] = a * vop_ref[0][0] + d[0][0];
        sprite_ref[0][1] = a * vop_ref[0][1] + d[0][1];
        sprite_ref[1][0] = a * vop_ref[1][0] + d[0][0] + d[1][0];
        sprite_ref[1][1] = a * vop_ref[1][1] + d[0][1] + d[1][1];
        sprite_ref[2][0] = a * vop_ref[2][0] + d[0][0] + d[2][0];
        sprite_ref[2][1] = a * vop_ref[2][1] + d[0][1] + d[2][1];
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    } else {
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        sprite_ref[0][0] = (a >> 1) * (2 * vop_ref[0][0] + d[0][0]);
        sprite_ref[0][1] = (a >> 1) * (2 * vop_ref[0][1] + d[0][1]);
        sprite_ref[1][0] = (a >> 1) * (2 * vop_ref[1][0] + d[0][0] + d[1][0]);
        sprite_ref[1][1] = (a >> 1) * (2 * vop_ref[1][1] + d[0][1] + d[1][1]);
        sprite_ref[2][0] = (a >> 1) * (2 * vop_ref[2][0] + d[0][0] + d[2][0]);
        sprite_ref[2][1] = (a >> 1) * (2 * vop_ref[2][1] + d[0][1] + d[2][1]);
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    }
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    /* sprite_ref[3][0] = (a >> 1) * (2 * vop_ref[3][0] + d[0][0] + d[1][0] + d[2][0] + d[3][0]);
     * sprite_ref[3][1] = (a >> 1) * (2 * vop_ref[3][1] + d[0][1] + d[1][1] + d[2][1] + d[3][1]); */

    /* this is mostly identical to the mpeg4 std (and is totally unreadable
     * because of that...). Perhaps it should be reordered to be more readable.
     * The idea behind this virtual_ref mess is to be able to use shifts later
     * per pixel instead of divides so the distance between points is converted
     * from w&h based to w2&h2 based which are of the 2^x form. */
    virtual_ref[0][0] = 16 * (vop_ref[0][0] + w2) +
                         ROUNDED_DIV(((w - w2) *
                                      (r * sprite_ref[0][0] - 16 * vop_ref[0][0]) +
                                      w2 * (r * sprite_ref[1][0] - 16 * vop_ref[1][0])), w);
    virtual_ref[0][1] = 16 * vop_ref[0][1] +
                        ROUNDED_DIV(((w - w2) *
                                     (r * sprite_ref[0][1] - 16 * vop_ref[0][1]) +
                                     w2 * (r * sprite_ref[1][1] - 16 * vop_ref[1][1])), w);
    virtual_ref[1][0] = 16 * vop_ref[0][0] +
                        ROUNDED_DIV(((h - h2) * (r * sprite_ref[0][0] - 16 * vop_ref[0][0]) +
                                     h2 * (r * sprite_ref[2][0] - 16 * vop_ref[2][0])), h);
    virtual_ref[1][1] = 16 * (vop_ref[0][1] + h2) +
                        ROUNDED_DIV(((h - h2) * (r * sprite_ref[0][1] - 16 * vop_ref[0][1]) +
                                     h2 * (r * sprite_ref[2][1] - 16 * vop_ref[2][1])), h);

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    switch (ctx->num_sprite_warping_points) {
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    case 0:
        s->sprite_offset[0][0] =
        s->sprite_offset[0][1] =
        s->sprite_offset[1][0] =
        s->sprite_offset[1][1] = 0;
        s->sprite_delta[0][0]  = a;
        s->sprite_delta[0][1]  =
        s->sprite_delta[1][0]  = 0;
        s->sprite_delta[1][1]  = a;
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        ctx->sprite_shift[0]   =
        ctx->sprite_shift[1]   = 0;
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        break;
    case 1:     // GMC only
        s->sprite_offset[0][0] = sprite_ref[0][0] - a * vop_ref[0][0];
        s->sprite_offset[0][1] = sprite_ref[0][1] - a * vop_ref[0][1];
        s->sprite_offset[1][0] = ((sprite_ref[0][0] >> 1) | (sprite_ref[0][0] & 1)) -
                                 a * (vop_ref[0][0] / 2);
        s->sprite_offset[1][1] = ((sprite_ref[0][1] >> 1) | (sprite_ref[0][1] & 1)) -
                                 a * (vop_ref[0][1] / 2);
        s->sprite_delta[0][0]  = a;
        s->sprite_delta[0][1]  =
        s->sprite_delta[1][0]  = 0;
        s->sprite_delta[1][1]  = a;
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        ctx->sprite_shift[0]   =
        ctx->sprite_shift[1]   = 0;
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        break;
    case 2:
        s->sprite_offset[0][0] = (sprite_ref[0][0] << (alpha + rho)) +
                                 (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
                                 (-vop_ref[0][0]) +
                                 (r * sprite_ref[0][1] - virtual_ref[0][1]) *
                                 (-vop_ref[0][1]) + (1 << (alpha + rho - 1));
        s->sprite_offset[0][1] = (sprite_ref[0][1] << (alpha + rho)) +
                                 (-r * sprite_ref[0][1] + virtual_ref[0][1]) *
                                 (-vop_ref[0][0]) +
                                 (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
                                 (-vop_ref[0][1]) + (1 << (alpha + rho - 1));
        s->sprite_offset[1][0] = ((-r * sprite_ref[0][0] + virtual_ref[0][0]) *
                                  (-2 * vop_ref[0][0] + 1) +
                                  (r * sprite_ref[0][1] - virtual_ref[0][1]) *
                                  (-2 * vop_ref[0][1] + 1) + 2 * w2 * r *
                                  sprite_ref[0][0] - 16 * w2 + (1 << (alpha + rho + 1)));
        s->sprite_offset[1][1] = ((-r * sprite_ref[0][1] + virtual_ref[0][1]) *
                                  (-2 * vop_ref[0][0] + 1) +
                                  (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
                                  (-2 * vop_ref[0][1] + 1) + 2 * w2 * r *
                                  sprite_ref[0][1] - 16 * w2 + (1 << (alpha + rho + 1)));
        s->sprite_delta[0][0] = (-r * sprite_ref[0][0] + virtual_ref[0][0]);
        s->sprite_delta[0][1] = (+r * sprite_ref[0][1] - virtual_ref[0][1]);
        s->sprite_delta[1][0] = (-r * sprite_ref[0][1] + virtual_ref[0][1]);
        s->sprite_delta[1][1] = (-r * sprite_ref[0][0] + virtual_ref[0][0]);

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        ctx->sprite_shift[0]  = alpha + rho;
        ctx->sprite_shift[1]  = alpha + rho + 2;
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        break;
    case 3:
        min_ab = FFMIN(alpha, beta);
        w3     = w2 >> min_ab;
        h3     = h2 >> min_ab;
        s->sprite_offset[0][0] = (sprite_ref[0][0] << (alpha + beta + rho - min_ab)) +
                                 (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
                                 h3 * (-vop_ref[0][0]) +
                                 (-r * sprite_ref[0][0] + virtual_ref[1][0]) *
                                 w3 * (-vop_ref[0][1]) +
                                 (1 << (alpha + beta + rho - min_ab - 1));
        s->sprite_offset[0][1] = (sprite_ref[0][1] << (alpha + beta + rho - min_ab)) +
                                 (-r * sprite_ref[0][1] + virtual_ref[0][1]) *
                                 h3 * (-vop_ref[0][0]) +
                                 (-r * sprite_ref[0][1] + virtual_ref[1][1]) *
                                 w3 * (-vop_ref[0][1]) +
                                 (1 << (alpha + beta + rho - min_ab - 1));
        s->sprite_offset[1][0] = (-r * sprite_ref[0][0] + virtual_ref[0][0]) *
                                 h3 * (-2 * vop_ref[0][0] + 1) +
                                 (-r * sprite_ref[0][0] + virtual_ref[1][0]) *
                                 w3 * (-2 * vop_ref[0][1] + 1) + 2 * w2 * h3 *
                                 r * sprite_ref[0][0] - 16 * w2 * h3 +
                                 (1 << (alpha + beta + rho - min_ab + 1));
        s->sprite_offset[1][1] = (-r * sprite_ref[0][1] + virtual_ref[0][1]) *
                                 h3 * (-2 * vop_ref[0][0] + 1) +
                                 (-r * sprite_ref[0][1] + virtual_ref[1][1]) *
                                 w3 * (-2 * vop_ref[0][1] + 1) + 2 * w2 * h3 *
                                 r * sprite_ref[0][1] - 16 * w2 * h3 +
                                 (1 << (alpha + beta + rho - min_ab + 1));
        s->sprite_delta[0][0] = (-r * sprite_ref[0][0] + virtual_ref[0][0]) * h3;
        s->sprite_delta[0][1] = (-r * sprite_ref[0][0] + virtual_ref[1][0]) * w3;
        s->sprite_delta[1][0] = (-r * sprite_ref[0][1] + virtual_ref[0][1]) * h3;
        s->sprite_delta[1][1] = (-r * sprite_ref[0][1] + virtual_ref[1][1]) * w3;

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        ctx->sprite_shift[0]  = alpha + beta + rho - min_ab;
        ctx->sprite_shift[1]  = alpha + beta + rho - min_ab + 2;
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        break;
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    }
    /* try to simplify the situation */
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    if (s->sprite_delta[0][0] == a << ctx->sprite_shift[0] &&
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        s->sprite_delta[0][1] == 0 &&
        s->sprite_delta[1][0] == 0 &&
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        s->sprite_delta[1][1] == a << ctx->sprite_shift[0]) {
        s->sprite_offset[0][0] >>= ctx->sprite_shift[0];
        s->sprite_offset[0][1] >>= ctx->sprite_shift[0];
        s->sprite_offset[1][0] >>= ctx->sprite_shift[1];
        s->sprite_offset[1][1] >>= ctx->sprite_shift[1];
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        s->sprite_delta[0][0] = a;
        s->sprite_delta[0][1] = 0;
        s->sprite_delta[1][0] = 0;
        s->sprite_delta[1][1] = a;
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        ctx->sprite_shift[0] = 0;
        ctx->sprite_shift[1] = 0;
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        s->real_sprite_warping_points = 1;
    } else {
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        int shift_y = 16 - ctx->sprite_shift[0];
        int shift_c = 16 - ctx->sprite_shift[1];
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        for (i = 0; i < 2; i++) {
            s->sprite_offset[0][i] <<= shift_y;
            s->sprite_offset[1][i] <<= shift_c;
            s->sprite_delta[0][i]  <<= shift_y;
            s->sprite_delta[1][i]  <<= shift_y;
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            ctx->sprite_shift[i]     = 16;
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        }
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        s->real_sprite_warping_points = ctx->num_sprite_warping_points;
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    }
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    return 0;
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}

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static int decode_new_pred(Mpeg4DecContext *ctx, GetBitContext *gb) {
    int len = FFMIN(ctx->time_increment_bits + 3, 15);
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    get_bits(gb, len);
    if (get_bits1(gb))
        get_bits(gb, len);
    check_marker(gb, "after new_pred");

    return 0;
}

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/**
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 * Decode the next video packet.
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 * @return <0 if something went wrong
 */
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int ff_mpeg4_decode_video_packet_header(Mpeg4DecContext *ctx)
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{
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    MpegEncContext *s = &ctx->m;

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    int mb_num_bits      = av_log2(s->mb_num - 1) + 1;
    int header_extension = 0, mb_num, len;
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    /* is there enough space left for a video packet + header */
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    if (get_bits_count(&s->gb) > s->gb.size_in_bits - 20)
        return -1;
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    for (len = 0; len < 32; len++)
        if (get_bits1(&s->gb))
            break;
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    if (len != ff_mpeg4_get_video_packet_prefix_length(s)) {
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        av_log(s->avctx, AV_LOG_ERROR, "marker does not match f_code\n");
        return -1;
    }

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    if (ctx->shape != RECT_SHAPE) {
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        header_extension = get_bits1(&s->gb);
        // FIXME more stuff here
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    }

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    mb_num = get_bits(&s->gb, mb_num_bits);
    if (mb_num >= s->mb_num) {
        av_log(s->avctx, AV_LOG_ERROR,
               "illegal mb_num in video packet (%d %d) \n", mb_num, s->mb_num);
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        return -1;
    }

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    s->mb_x = mb_num % s->mb_width;
    s->mb_y = mb_num / s->mb_width;
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    if (ctx->shape != BIN_ONLY_SHAPE) {
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        int qscale = get_bits(&s->gb, s->quant_precision);
        if (qscale)
            s->chroma_qscale = s->qscale = qscale;
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    }

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    if (ctx->shape == RECT_SHAPE)
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        header_extension = get_bits1(&s->gb);

    if (header_extension) {
        int time_incr = 0;
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        while (get_bits1(&s->gb) != 0)
            time_incr++;

        check_marker(&s->gb, "before time_increment in video packed header");
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        skip_bits(&s->gb, ctx->time_increment_bits);      /* time_increment */
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        check_marker(&s->gb, "before vop_coding_type in video packed header");

        skip_bits(&s->gb, 2); /* vop coding type */
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        // FIXME not rect stuff here
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        if (ctx->shape != BIN_ONLY_SHAPE) {
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            skip_bits(&s->gb, 3); /* intra dc vlc threshold */
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            // FIXME don't just ignore everything
            if (s->pict_type == AV_PICTURE_TYPE_S &&
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                ctx->vol_sprite_usage == GMC_SPRITE) {
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                if (mpeg4_decode_sprite_trajectory(ctx, &s->gb) < 0)
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                    return AVERROR_INVALIDDATA;
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                av_log(s->avctx, AV_LOG_ERROR, "untested\n");
            }

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            // FIXME reduced res stuff here
460

461
            if (s->pict_type != AV_PICTURE_TYPE_I) {
462
                int f_code = get_bits(&s->gb, 3);       /* fcode_for */
463 464 465
                if (f_code == 0)
                    av_log(s->avctx, AV_LOG_ERROR,
                           "Error, video packet header damaged (f_code=0)\n");
466
            }
467
            if (s->pict_type == AV_PICTURE_TYPE_B) {
468
                int b_code = get_bits(&s->gb, 3);
469 470 471
                if (b_code == 0)
                    av_log(s->avctx, AV_LOG_ERROR,
                           "Error, video packet header damaged (b_code=0)\n");
472 473 474
            }
        }
    }
475
    if (ctx->new_pred)
476
        decode_new_pred(ctx, &s->gb);
477 478 479 480 481

    return 0;
}

/**
482
 * Get the average motion vector for a GMC MB.
483
 * @param n either 0 for the x component or 1 for y
484
 * @return the average MV for a GMC MB
485
 */
486
static inline int get_amv(Mpeg4DecContext *ctx, int n)
487
{
488
    MpegEncContext *s = &ctx->m;
489
    int x, y, mb_v, sum, dx, dy, shift;
490 491
    int len     = 1 << (s->f_code + 4);
    const int a = s->sprite_warping_accuracy;
492

493
    if (s->workaround_bugs & FF_BUG_AMV)
494 495
        len >>= s->quarter_sample;

496
    if (s->real_sprite_warping_points == 1) {
497
        if (ctx->divx_version == 500 && ctx->divx_build == 413)
498 499 500 501 502 503
            sum = s->sprite_offset[0][n] / (1 << (a - s->quarter_sample));
        else
            sum = RSHIFT(s->sprite_offset[0][n] << s->quarter_sample, a);
    } else {
        dx    = s->sprite_delta[n][0];
        dy    = s->sprite_delta[n][1];
504
        shift = ctx->sprite_shift[0];
505 506
        if (n)
            dy -= 1 << (shift + a + 1);
507
        else
508 509 510 511 512
            dx -= 1 << (shift + a + 1);
        mb_v = s->sprite_offset[0][n] + dx * s->mb_x * 16 + dy * s->mb_y * 16;

        sum = 0;
        for (y = 0; y < 16; y++) {
513 514
            int v;

515 516 517 518 519
            v = mb_v + dy * y;
            // FIXME optimize
            for (x = 0; x < 16; x++) {
                sum += v >> shift;
                v   += dx;
520 521
            }
        }
522
        sum = RSHIFT(sum, a + 8 - s->quarter_sample);
523 524
    }

525 526 527 528
    if (sum < -len)
        sum = -len;
    else if (sum >= len)
        sum = len - 1;
529 530 531 532 533

    return sum;
}

/**
534
 * Decode the dc value.
535 536 537 538
 * @param n block index (0-3 are luma, 4-5 are chroma)
 * @param dir_ptr the prediction direction will be stored here
 * @return the quantized dc
 */
539
static inline int mpeg4_decode_dc(MpegEncContext *s, int n, int *dir_ptr)
540 541 542 543 544 545 546
{
    int level, code;

    if (n < 4)
        code = get_vlc2(&s->gb, dc_lum.table, DC_VLC_BITS, 1);
    else
        code = get_vlc2(&s->gb, dc_chrom.table, DC_VLC_BITS, 1);
547 548

    if (code < 0 || code > 9 /* && s->nbit < 9 */) {
549 550 551
        av_log(s->avctx, AV_LOG_ERROR, "illegal dc vlc\n");
        return -1;
    }
552

553 554 555
    if (code == 0) {
        level = 0;
    } else {
556 557 558 559 560 561
        if (IS_3IV1) {
            if (code == 1)
                level = 2 * get_bits1(&s->gb) - 1;
            else {
                if (get_bits1(&s->gb))
                    level = get_bits(&s->gb, code - 1) + (1 << (code - 1));
562
                else
563
                    level = -get_bits(&s->gb, code - 1) - (1 << (code - 1));
564
            }
565
        } else {
566 567 568
            level = get_xbits(&s->gb, code);
        }

569 570
        if (code > 8) {
            if (get_bits1(&s->gb) == 0) { /* marker */
571
                if (s->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)) {
572 573 574 575 576 577 578 579 580 581 582
                    av_log(s->avctx, AV_LOG_ERROR, "dc marker bit missing\n");
                    return -1;
                }
            }
        }
    }

    return ff_mpeg4_pred_dc(s, n, level, dir_ptr, 0);
}

/**
583
 * Decode first partition.
584 585
 * @return number of MBs decoded or <0 if an error occurred
 */
586
static int mpeg4_decode_partition_a(Mpeg4DecContext *ctx)
587
{
588
    MpegEncContext *s = &ctx->m;
589
    int mb_num = 0;
590 591 592
    static const int8_t quant_tab[4] = { -1, -2, 1, 2 };

    /* decode first partition */
593 594
    s->first_slice_line = 1;
    for (; s->mb_y < s->mb_height; s->mb_y++) {
595
        ff_init_block_index(s);
596 597
        for (; s->mb_x < s->mb_width; s->mb_x++) {
            const int xy = s->mb_x + s->mb_y * s->mb_stride;
598
            int cbpc;
599
            int dir = 0;
600 601 602

            mb_num++;
            ff_update_block_index(s);
603 604
            if (s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y + 1)
                s->first_slice_line = 0;
605

606
            if (s->pict_type == AV_PICTURE_TYPE_I) {
607 608
                int i;

609 610 611
                do {
                    if (show_bits_long(&s->gb, 19) == DC_MARKER)
                        return mb_num - 1;
612

613
                    cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
614 615 616
                    if (cbpc < 0) {
                        av_log(s->avctx, AV_LOG_ERROR,
                               "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
617 618
                        return -1;
                    }
619
                } while (cbpc == 8);
620

621
                s->cbp_table[xy]               = cbpc & 3;
622
                s->current_picture.mb_type[xy] = MB_TYPE_INTRA;
623
                s->mb_intra                    = 1;
624

625
                if (cbpc & 4)
626 627
                    ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);

628 629 630 631
                s->current_picture.qscale_table[xy] = s->qscale;

                s->mbintra_table[xy] = 1;
                for (i = 0; i < 6; i++) {
632
                    int dc_pred_dir;
633 634 635 636
                    int dc = mpeg4_decode_dc(s, i, &dc_pred_dir);
                    if (dc < 0) {
                        av_log(s->avctx, AV_LOG_ERROR,
                               "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
637 638
                        return -1;
                    }
639 640 641
                    dir <<= 1;
                    if (dc_pred_dir)
                        dir |= 1;
642
                }
643 644
                s->pred_dir_table[xy] = dir;
            } else { /* P/S_TYPE */
645
                int mx, my, pred_x, pred_y, bits;
646 647
                int16_t *const mot_val = s->current_picture.motion_val[0][s->block_index[0]];
                const int stride       = s->b8_stride * 2;
648 649

try_again:
650 651 652 653
                bits = show_bits(&s->gb, 17);
                if (bits == MOTION_MARKER)
                    return mb_num - 1;

654
                skip_bits1(&s->gb);
655
                if (bits & 0x10000) {
656
                    /* skip mb */
657
                    if (s->pict_type == AV_PICTURE_TYPE_S &&
658
                        ctx->vol_sprite_usage == GMC_SPRITE) {
659 660 661 662
                        s->current_picture.mb_type[xy] = MB_TYPE_SKIP  |
                                                         MB_TYPE_16x16 |
                                                         MB_TYPE_GMC   |
                                                         MB_TYPE_L0;
663 664
                        mx = get_amv(ctx, 0);
                        my = get_amv(ctx, 1);
665 666 667 668 669
                    } else {
                        s->current_picture.mb_type[xy] = MB_TYPE_SKIP  |
                                                         MB_TYPE_16x16 |
                                                         MB_TYPE_L0;
                        mx = my = 0;
670
                    }
671 672 673 674 675 676 677 678 679 680
                    mot_val[0]          =
                    mot_val[2]          =
                    mot_val[0 + stride] =
                    mot_val[2 + stride] = mx;
                    mot_val[1]          =
                    mot_val[3]          =
                    mot_val[1 + stride] =
                    mot_val[3 + stride] = my;

                    if (s->mbintra_table[xy])
681 682 683 684
                        ff_clean_intra_table_entries(s);
                    continue;
                }

685
                cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
686 687 688
                if (cbpc < 0) {
                    av_log(s->avctx, AV_LOG_ERROR,
                           "cbpc corrupted at %d %d\n", s->mb_x, s->mb_y);
689 690
                    return -1;
                }
691
                if (cbpc == 20)
692 693
                    goto try_again;

694
                s->cbp_table[xy] = cbpc & (8 + 3);  // 8 is dquant
695 696 697

                s->mb_intra = ((cbpc & 4) != 0);

698
                if (s->mb_intra) {
699
                    s->current_picture.mb_type[xy] = MB_TYPE_INTRA;
700 701 702 703 704 705 706 707 708 709 710
                    s->mbintra_table[xy] = 1;
                    mot_val[0]          =
                    mot_val[2]          =
                    mot_val[0 + stride] =
                    mot_val[2 + stride] = 0;
                    mot_val[1]          =
                    mot_val[3]          =
                    mot_val[1 + stride] =
                    mot_val[3 + stride] = 0;
                } else {
                    if (s->mbintra_table[xy])
711 712
                        ff_clean_intra_table_entries(s);

713
                    if (s->pict_type == AV_PICTURE_TYPE_S &&
714
                        ctx->vol_sprite_usage == GMC_SPRITE &&
715 716 717 718
                        (cbpc & 16) == 0)
                        s->mcsel = get_bits1(&s->gb);
                    else
                        s->mcsel = 0;
719 720 721 722

                    if ((cbpc & 16) == 0) {
                        /* 16x16 motion prediction */

723
                        ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
724
                        if (!s->mcsel) {
725
                            mx = ff_h263_decode_motion(s, pred_x, s->f_code);
726 727 728
                            if (mx >= 0xffff)
                                return -1;

729
                            my = ff_h263_decode_motion(s, pred_y, s->f_code);
730 731
                            if (my >= 0xffff)
                                return -1;
732 733
                            s->current_picture.mb_type[xy] = MB_TYPE_16x16 |
                                                             MB_TYPE_L0;
734
                        } else {
735 736
                            mx = get_amv(ctx, 0);
                            my = get_amv(ctx, 1);
737 738 739
                            s->current_picture.mb_type[xy] = MB_TYPE_16x16 |
                                                             MB_TYPE_GMC   |
                                                             MB_TYPE_L0;
740 741
                        }

742 743 744 745 746 747 748 749
                        mot_val[0]          =
                        mot_val[2]          =
                        mot_val[0 + stride] =
                        mot_val[2 + stride] = mx;
                        mot_val[1]          =
                        mot_val[3]          =
                        mot_val[1 + stride] =
                        mot_val[3 + stride] = my;
750 751
                    } else {
                        int i;
752 753 754 755
                        s->current_picture.mb_type[xy] = MB_TYPE_8x8 |
                                                         MB_TYPE_L0;
                        for (i = 0; i < 4; i++) {
                            int16_t *mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
756
                            mx = ff_h263_decode_motion(s, pred_x, s->f_code);
757 758 759
                            if (mx >= 0xffff)
                                return -1;

760
                            my = ff_h263_decode_motion(s, pred_y, s->f_code);
761 762 763 764 765 766 767 768 769
                            if (my >= 0xffff)
                                return -1;
                            mot_val[0] = mx;
                            mot_val[1] = my;
                        }
                    }
                }
            }
        }
770
        s->mb_x = 0;
771 772 773 774 775 776 777 778 779
    }

    return mb_num;
}

/**
 * decode second partition.
 * @return <0 if an error occurred
 */
780 781 782
static int mpeg4_decode_partition_b(MpegEncContext *s, int mb_count)
{
    int mb_num = 0;
783 784
    static const int8_t quant_tab[4] = { -1, -2, 1, 2 };

785 786 787
    s->mb_x = s->resync_mb_x;
    s->first_slice_line = 1;
    for (s->mb_y = s->resync_mb_y; mb_num < mb_count; s->mb_y++) {
788
        ff_init_block_index(s);
789 790
        for (; mb_num < mb_count && s->mb_x < s->mb_width; s->mb_x++) {
            const int xy = s->mb_x + s->mb_y * s->mb_stride;
791 792 793

            mb_num++;
            ff_update_block_index(s);
794 795 796 797 798 799 800 801 802
            if (s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y + 1)
                s->first_slice_line = 0;

            if (s->pict_type == AV_PICTURE_TYPE_I) {
                int ac_pred = get_bits1(&s->gb);
                int cbpy    = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
                if (cbpy < 0) {
                    av_log(s->avctx, AV_LOG_ERROR,
                           "cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
803 804 805
                    return -1;
                }

806 807 808
                s->cbp_table[xy]               |= cbpy << 2;
                s->current_picture.mb_type[xy] |= ac_pred * MB_TYPE_ACPRED;
            } else { /* P || S_TYPE */
809
                if (IS_INTRA(s->current_picture.mb_type[xy])) {
810 811
                    int i;
                    int dir     = 0;
812
                    int ac_pred = get_bits1(&s->gb);
813
                    int cbpy    = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
814

815 816 817
                    if (cbpy < 0) {
                        av_log(s->avctx, AV_LOG_ERROR,
                               "I cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
818 819 820
                        return -1;
                    }

821
                    if (s->cbp_table[xy] & 8)
822
                        ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
823
                    s->current_picture.qscale_table[xy] = s->qscale;
824

825
                    for (i = 0; i < 6; i++) {
826
                        int dc_pred_dir;
827 828 829 830
                        int dc = mpeg4_decode_dc(s, i, &dc_pred_dir);
                        if (dc < 0) {
                            av_log(s->avctx, AV_LOG_ERROR,
                                   "DC corrupted at %d %d\n", s->mb_x, s->mb_y);
831 832
                            return -1;
                        }
833 834 835
                        dir <<= 1;
                        if (dc_pred_dir)
                            dir |= 1;
836
                    }
837 838 839 840
                    s->cbp_table[xy]               &= 3;  // remove dquant
                    s->cbp_table[xy]               |= cbpy << 2;
                    s->current_picture.mb_type[xy] |= ac_pred * MB_TYPE_ACPRED;
                    s->pred_dir_table[xy]           = dir;
841 842
                } else if (IS_SKIP(s->current_picture.mb_type[xy])) {
                    s->current_picture.qscale_table[xy] = s->qscale;
843 844
                    s->cbp_table[xy]                    = 0;
                } else {
845
                    int cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
846

847 848 849
                    if (cbpy < 0) {
                        av_log(s->avctx, AV_LOG_ERROR,
                               "P cbpy corrupted at %d %d\n", s->mb_x, s->mb_y);
850 851 852
                        return -1;
                    }

853
                    if (s->cbp_table[xy] & 8)
854
                        ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
855
                    s->current_picture.qscale_table[xy] = s->qscale;
856

857 858
                    s->cbp_table[xy] &= 3;  // remove dquant
                    s->cbp_table[xy] |= (cbpy ^ 0xf) << 2;
859 860 861
                }
            }
        }
862 863 864
        if (mb_num >= mb_count)
            return 0;
        s->mb_x = 0;
865 866 867 868 869
    }
    return 0;
}

/**
870
 * Decode the first and second partition.
871 872
 * @return <0 if error (and sets error type in the error_status_table)
 */
873
int ff_mpeg4_decode_partitions(Mpeg4DecContext *ctx)
874
{
875
    MpegEncContext *s = &ctx->m;
876
    int mb_num;
877 878
    const int part_a_error = s->pict_type == AV_PICTURE_TYPE_I ? (ER_DC_ERROR | ER_MV_ERROR) : ER_MV_ERROR;
    const int part_a_end   = s->pict_type == AV_PICTURE_TYPE_I ? (ER_DC_END   | ER_MV_END)   : ER_MV_END;
879

880
    mb_num = mpeg4_decode_partition_a(ctx);
881 882 883
    if (mb_num < 0) {
        ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
                        s->mb_x, s->mb_y, part_a_error);
884 885 886
        return -1;
    }

887
    if (s->resync_mb_x + s->resync_mb_y * s->mb_width + mb_num > s->mb_num) {
888
        av_log(s->avctx, AV_LOG_ERROR, "slice below monitor ...\n");
889 890
        ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
                        s->mb_x, s->mb_y, part_a_error);
891 892 893
        return -1;
    }

894
    s->mb_num_left = mb_num;
895

896 897
    if (s->pict_type == AV_PICTURE_TYPE_I) {
        while (show_bits(&s->gb, 9) == 1)
898
            skip_bits(&s->gb, 9);
899 900 901 902
        if (get_bits_long(&s->gb, 19) != DC_MARKER) {
            av_log(s->avctx, AV_LOG_ERROR,
                   "marker missing after first I partition at %d %d\n",
                   s->mb_x, s->mb_y);
903 904
            return -1;
        }
905 906
    } else {
        while (show_bits(&s->gb, 10) == 1)
907
            skip_bits(&s->gb, 10);
908 909 910 911
        if (get_bits(&s->gb, 17) != MOTION_MARKER) {
            av_log(s->avctx, AV_LOG_ERROR,
                   "marker missing after first P partition at %d %d\n",
                   s->mb_x, s->mb_y);
912 913 914
            return -1;
        }
    }
915 916
    ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
                    s->mb_x - 1, s->mb_y, part_a_end);
917

918 919 920 921
    if (mpeg4_decode_partition_b(s, mb_num) < 0) {
        if (s->pict_type == AV_PICTURE_TYPE_P)
            ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
                            s->mb_x, s->mb_y, ER_DC_ERROR);
922
        return -1;
923 924 925 926
    } else {
        if (s->pict_type == AV_PICTURE_TYPE_P)
            ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
                            s->mb_x - 1, s->mb_y, ER_DC_END);
927 928 929 930 931 932
    }

    return 0;
}

/**
933
 * Decode a block.
934 935
 * @return <0 if an error occurred
 */
936
static inline int mpeg4_decode_block(Mpeg4DecContext *ctx, int16_t *block,
937
                                     int n, int coded, int intra, int rvlc)
938
{
939
    MpegEncContext *s = &ctx->m;
940
    int level, i, last, run, qmul, qadd;
941
    int av_uninit(dc_pred_dir);
942 943 944 945 946 947 948
    RLTable *rl;
    RL_VLC_ELEM *rl_vlc;
    const uint8_t *scan_table;

    // Note intra & rvlc should be optimized away if this is inlined

    if (intra) {
949
        if (ctx->use_intra_dc_vlc) {
950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965
            /* DC coef */
            if (s->partitioned_frame) {
                level = s->dc_val[0][s->block_index[n]];
                if (n < 4)
                    level = FASTDIV((level + (s->y_dc_scale >> 1)), s->y_dc_scale);
                else
                    level = FASTDIV((level + (s->c_dc_scale >> 1)), s->c_dc_scale);
                dc_pred_dir = (s->pred_dir_table[s->mb_x + s->mb_y * s->mb_stride] << n) & 32;
            } else {
                level = mpeg4_decode_dc(s, n, &dc_pred_dir);
                if (level < 0)
                    return -1;
            }
            block[0] = level;
            i        = 0;
        } else {
966 967
            i = -1;
            ff_mpeg4_pred_dc(s, n, 0, &dc_pred_dir, 0);
968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984
        }
        if (!coded)
            goto not_coded;

        if (rvlc) {
            rl     = &ff_rvlc_rl_intra;
            rl_vlc = ff_rvlc_rl_intra.rl_vlc[0];
        } else {
            rl     = &ff_mpeg4_rl_intra;
            rl_vlc = ff_mpeg4_rl_intra.rl_vlc[0];
        }
        if (s->ac_pred) {
            if (dc_pred_dir == 0)
                scan_table = s->intra_v_scantable.permutated;  /* left */
            else
                scan_table = s->intra_h_scantable.permutated;  /* top */
        } else {
985
            scan_table = s->intra_scantable.permutated;
986 987 988
        }
        qmul = 1;
        qadd = 0;
989 990 991 992 993 994
    } else {
        i = -1;
        if (!coded) {
            s->block_last_index[n] = i;
            return 0;
        }
995 996 997 998
        if (rvlc)
            rl = &ff_rvlc_rl_inter;
        else
            rl = &ff_h263_rl_inter;
999 1000 1001

        scan_table = s->intra_scantable.permutated;

1002 1003 1004 1005
        if (s->mpeg_quant) {
            qmul = 1;
            qadd = 0;
            if (rvlc)
1006
                rl_vlc = ff_rvlc_rl_inter.rl_vlc[0];
1007
            else
1008
                rl_vlc = ff_h263_rl_inter.rl_vlc[0];
1009
        } else {
1010 1011
            qmul = s->qscale << 1;
            qadd = (s->qscale - 1) | 1;
1012
            if (rvlc)
1013
                rl_vlc = ff_rvlc_rl_inter.rl_vlc[s->qscale];
1014
            else
1015
                rl_vlc = ff_h263_rl_inter.rl_vlc[s->qscale];
1016 1017
        }
    }
1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031
    {
        OPEN_READER(re, &s->gb);
        for (;;) {
            UPDATE_CACHE(re, &s->gb);
            GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 0);
            if (level == 0) {
                /* escape */
                if (rvlc) {
                    if (SHOW_UBITS(re, &s->gb, 1) == 0) {
                        av_log(s->avctx, AV_LOG_ERROR,
                               "1. marker bit missing in rvlc esc\n");
                        return -1;
                    }
                    SKIP_CACHE(re, &s->gb, 1);
1032

1033 1034 1035 1036
                    last = SHOW_UBITS(re, &s->gb, 1);
                    SKIP_CACHE(re, &s->gb, 1);
                    run = SHOW_UBITS(re, &s->gb, 6);
                    SKIP_COUNTER(re, &s->gb, 1 + 1 + 6);
1037 1038
                    UPDATE_CACHE(re, &s->gb);

1039 1040 1041 1042 1043 1044
                    if (SHOW_UBITS(re, &s->gb, 1) == 0) {
                        av_log(s->avctx, AV_LOG_ERROR,
                               "2. marker bit missing in rvlc esc\n");
                        return -1;
                    }
                    SKIP_CACHE(re, &s->gb, 1);
1045

1046 1047
                    level = SHOW_UBITS(re, &s->gb, 11);
                    SKIP_CACHE(re, &s->gb, 11);
1048

1049 1050 1051
                    if (SHOW_UBITS(re, &s->gb, 5) != 0x10) {
                        av_log(s->avctx, AV_LOG_ERROR, "reverse esc missing\n");
                        return -1;
1052
                    }
1053
                    SKIP_CACHE(re, &s->gb, 5);
1054

1055 1056 1057
                    level = level * qmul + qadd;
                    level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
                    SKIP_COUNTER(re, &s->gb, 1 + 11 + 5 + 1);
1058

1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088
                    i += run + 1;
                    if (last)
                        i += 192;
                } else {
                    int cache;
                    cache = GET_CACHE(re, &s->gb);

                    if (IS_3IV1)
                        cache ^= 0xC0000000;

                    if (cache & 0x80000000) {
                        if (cache & 0x40000000) {
                            /* third escape */
                            SKIP_CACHE(re, &s->gb, 2);
                            last = SHOW_UBITS(re, &s->gb, 1);
                            SKIP_CACHE(re, &s->gb, 1);
                            run = SHOW_UBITS(re, &s->gb, 6);
                            SKIP_COUNTER(re, &s->gb, 2 + 1 + 6);
                            UPDATE_CACHE(re, &s->gb);

                            if (IS_3IV1) {
                                level = SHOW_SBITS(re, &s->gb, 12);
                                LAST_SKIP_BITS(re, &s->gb, 12);
                            } else {
                                if (SHOW_UBITS(re, &s->gb, 1) == 0) {
                                    av_log(s->avctx, AV_LOG_ERROR,
                                           "1. marker bit missing in 3. esc\n");
                                    return -1;
                                }
                                SKIP_CACHE(re, &s->gb, 1);
1089

1090 1091
                                level = SHOW_SBITS(re, &s->gb, 12);
                                SKIP_CACHE(re, &s->gb, 12);
1092

1093 1094 1095 1096 1097
                                if (SHOW_UBITS(re, &s->gb, 1) == 0) {
                                    av_log(s->avctx, AV_LOG_ERROR,
                                           "2. marker bit missing in 3. esc\n");
                                    return -1;
                                }
1098

1099
                                SKIP_COUNTER(re, &s->gb, 1 + 12 + 1);
1100 1101 1102
                            }

#if 0
1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120
                            if (s->error_recognition >= FF_ER_COMPLIANT) {
                                const int abs_level= FFABS(level);
                                if (abs_level<=MAX_LEVEL && run<=MAX_RUN) {
                                    const int run1= run - rl->max_run[last][abs_level] - 1;
                                    if (abs_level <= rl->max_level[last][run]) {
                                        av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, vlc encoding possible\n");
                                        return -1;
                                    }
                                    if (s->error_recognition > FF_ER_COMPLIANT) {
                                        if (abs_level <= rl->max_level[last][run]*2) {
                                            av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 1 encoding possible\n");
                                            return -1;
                                        }
                                        if (run1 >= 0 && abs_level <= rl->max_level[last][run1]) {
                                            av_log(s->avctx, AV_LOG_ERROR, "illegal 3. esc, esc 2 encoding possible\n");
                                            return -1;
                                        }
                                    }
1121 1122 1123
                                }
                            }
#endif
1124 1125 1126 1127 1128 1129
                            if (level > 0)
                                level = level * qmul + qadd;
                            else
                                level = level * qmul - qadd;

                            if ((unsigned)(level + 2048) > 4095) {
1130
                                if (s->err_recognition & (AV_EF_BITSTREAM|AV_EF_AGGRESSIVE)) {
1131 1132 1133 1134 1135 1136 1137 1138
                                    if (level > 2560 || level < -2560) {
                                        av_log(s->avctx, AV_LOG_ERROR,
                                               "|level| overflow in 3. esc, qp=%d\n",
                                               s->qscale);
                                        return -1;
                                    }
                                }
                                level = level < 0 ? -2048 : 2047;
1139
                            }
1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150

                            i += run + 1;
                            if (last)
                                i += 192;
                        } else {
                            /* second escape */
                            SKIP_BITS(re, &s->gb, 2);
                            GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
                            i    += run + rl->max_run[run >> 7][level / qmul] + 1;  // FIXME opt indexing
                            level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
                            LAST_SKIP_BITS(re, &s->gb, 1);
1151
                        }
1152 1153 1154 1155 1156 1157 1158 1159
                    } else {
                        /* first escape */
                        SKIP_BITS(re, &s->gb, 1);
                        GET_RL_VLC(level, run, re, &s->gb, rl_vlc, TEX_VLC_BITS, 2, 1);
                        i    += run;
                        level = level + rl->max_level[run >> 7][(run - 1) & 63] * qmul;  // FIXME opt indexing
                        level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
                        LAST_SKIP_BITS(re, &s->gb, 1);
1160 1161 1162
                    }
                }
            } else {
1163
                i    += run;
1164 1165 1166
                level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
                LAST_SKIP_BITS(re, &s->gb, 1);
            }
1167 1168 1169 1170 1171 1172 1173 1174 1175 1176
            if (i > 62) {
                i -= 192;
                if (i & (~63)) {
                    av_log(s->avctx, AV_LOG_ERROR,
                           "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
                    return -1;
                }

                block[scan_table[i]] = level;
                break;
1177 1178 1179 1180
            }

            block[scan_table[i]] = level;
        }
1181
        CLOSE_READER(re, &s->gb);
1182
    }
1183 1184

not_coded:
1185
    if (intra) {
1186
        if (!ctx->use_intra_dc_vlc) {
1187 1188
            block[0] = ff_mpeg4_pred_dc(s, n, block[0], &dc_pred_dir, 0);

1189
            i -= i >> 31;  // if (i == -1) i = 0;
1190 1191
        }

1192
        ff_mpeg4_pred_ac(s, block, n, dc_pred_dir);
1193 1194
        if (s->ac_pred)
            i = 63;  // FIXME not optimal
1195 1196 1197 1198 1199 1200 1201 1202 1203
    }
    s->block_last_index[n] = i;
    return 0;
}

/**
 * decode partition C of one MB.
 * @return <0 if an error occurred
 */
Diego Biurrun's avatar
Diego Biurrun committed
1204
static int mpeg4_decode_partitioned_mb(MpegEncContext *s, int16_t block[6][64])
1205
{
1206
    Mpeg4DecContext *ctx = (Mpeg4DecContext *)s;
1207
    int cbp, mb_type;
1208
    const int xy = s->mb_x + s->mb_y * s->mb_stride;
1209

1210
    mb_type = s->current_picture.mb_type[xy];
1211
    cbp     = s->cbp_table[xy];
1212

1213
    ctx->use_intra_dc_vlc = s->qscale < ctx->intra_dc_threshold;
1214

1215
    if (s->current_picture.qscale_table[xy] != s->qscale)
1216
        ff_set_qscale(s, s->current_picture.qscale_table[xy]);
1217

1218 1219
    if (s->pict_type == AV_PICTURE_TYPE_P ||
        s->pict_type == AV_PICTURE_TYPE_S) {
1220
        int i;
1221
        for (i = 0; i < 4; i++) {
1222 1223
            s->mv[0][i][0] = s->current_picture.motion_val[0][s->block_index[i]][0];
            s->mv[0][i][1] = s->current_picture.motion_val[0][s->block_index[i]][1];
1224 1225 1226 1227 1228
        }
        s->mb_intra = IS_INTRA(mb_type);

        if (IS_SKIP(mb_type)) {
            /* skip mb */
1229
            for (i = 0; i < 6; i++)
1230
                s->block_last_index[i] = -1;
1231
            s->mv_dir  = MV_DIR_FORWARD;
1232
            s->mv_type = MV_TYPE_16X16;
1233
            if (s->pict_type == AV_PICTURE_TYPE_S
1234
                && ctx->vol_sprite_usage == GMC_SPRITE) {
1235
                s->mcsel      = 1;
1236
                s->mb_skipped = 0;
1237 1238
            } else {
                s->mcsel      = 0;
1239 1240
                s->mb_skipped = 1;
            }
1241
        } else if (s->mb_intra) {
1242
            s->ac_pred = IS_ACPRED(s->current_picture.mb_type[xy]);
1243 1244
        } else if (!s->mb_intra) {
            // s->mcsel = 0;  // FIXME do we need to init that?
1245 1246 1247 1248 1249 1250 1251 1252 1253 1254

            s->mv_dir = MV_DIR_FORWARD;
            if (IS_8X8(mb_type)) {
                s->mv_type = MV_TYPE_8X8;
            } else {
                s->mv_type = MV_TYPE_16X16;
            }
        }
    } else { /* I-Frame */
        s->mb_intra = 1;
1255
        s->ac_pred  = IS_ACPRED(s->current_picture.mb_type[xy]);
1256 1257 1258 1259 1260 1261 1262
    }

    if (!IS_SKIP(mb_type)) {
        int i;
        s->dsp.clear_blocks(s->block[0]);
        /* decode each block */
        for (i = 0; i < 6; i++) {
1263
            if (mpeg4_decode_block(ctx, block[i], i, cbp & 32, s->mb_intra, ctx->rvlc) < 0) {
1264 1265 1266
                av_log(s->avctx, AV_LOG_ERROR,
                       "texture corrupted at %d %d %d\n",
                       s->mb_x, s->mb_y, s->mb_intra);
1267 1268
                return -1;
            }
1269
            cbp += cbp;
1270 1271 1272 1273
        }
    }

    /* per-MB end of slice check */
1274
    if (--s->mb_num_left <= 0) {
1275
        if (mpeg4_is_resync(ctx))
1276 1277 1278
            return SLICE_END;
        else
            return SLICE_NOEND;
1279
    } else {
1280
        if (mpeg4_is_resync(ctx)) {
1281 1282
            const int delta = s->mb_x + 1 == s->mb_width ? 2 : 1;
            if (s->cbp_table[xy + delta])
1283 1284 1285 1286 1287 1288
                return SLICE_END;
        }
        return SLICE_OK;
    }
}

1289
static int mpeg4_decode_mb(MpegEncContext *s, int16_t block[6][64])
1290
{
1291
    Mpeg4DecContext *ctx = (Mpeg4DecContext *)s;
1292 1293 1294
    int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
    int16_t *mot_val;
    static int8_t quant_tab[4] = { -1, -2, 1, 2 };
1295
    const int xy = s->mb_x + s->mb_y * s->mb_stride;
1296

1297
    av_assert2(s->h263_pred);
1298

1299 1300 1301
    if (s->pict_type == AV_PICTURE_TYPE_P ||
        s->pict_type == AV_PICTURE_TYPE_S) {
        do {
1302 1303 1304
            if (get_bits1(&s->gb)) {
                /* skip mb */
                s->mb_intra = 0;
1305
                for (i = 0; i < 6; i++)
1306
                    s->block_last_index[i] = -1;
1307
                s->mv_dir  = MV_DIR_FORWARD;
1308
                s->mv_type = MV_TYPE_16X16;
1309
                if (s->pict_type == AV_PICTURE_TYPE_S &&
1310
                    ctx->vol_sprite_usage == GMC_SPRITE) {
1311 1312 1313 1314 1315
                    s->current_picture.mb_type[xy] = MB_TYPE_SKIP  |
                                                     MB_TYPE_GMC   |
                                                     MB_TYPE_16x16 |
                                                     MB_TYPE_L0;
                    s->mcsel       = 1;
1316 1317
                    s->mv[0][0][0] = get_amv(ctx, 0);
                    s->mv[0][0][1] = get_amv(ctx, 1);
1318 1319 1320 1321 1322 1323
                    s->mb_skipped  = 0;
                } else {
                    s->current_picture.mb_type[xy] = MB_TYPE_SKIP  |
                                                     MB_TYPE_16x16 |
                                                     MB_TYPE_L0;
                    s->mcsel       = 0;
1324 1325
                    s->mv[0][0][0] = 0;
                    s->mv[0][0][1] = 0;
1326
                    s->mb_skipped  = 1;
1327 1328 1329
                }
                goto end;
            }
1330
            cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
1331 1332 1333
            if (cbpc < 0) {
                av_log(s->avctx, AV_LOG_ERROR,
                       "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
1334 1335
                return -1;
            }
1336
        } while (cbpc == 20);
1337 1338

        s->dsp.clear_blocks(s->block[0]);
1339
        dquant      = cbpc & 8;
1340
        s->mb_intra = ((cbpc & 4) != 0);
1341 1342
        if (s->mb_intra)
            goto intra;
1343

1344
        if (s->pict_type == AV_PICTURE_TYPE_S &&
1345
            ctx->vol_sprite_usage == GMC_SPRITE && (cbpc & 16) == 0)
1346 1347 1348
            s->mcsel = get_bits1(&s->gb);
        else
            s->mcsel = 0;
1349
        cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1) ^ 0x0F;
1350 1351

        cbp = (cbpc & 3) | (cbpy << 2);
1352
        if (dquant)
1353
            ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);
1354 1355 1356
        if ((!s->progressive_sequence) &&
            (cbp || (s->workaround_bugs & FF_BUG_XVID_ILACE)))
            s->interlaced_dct = get_bits1(&s->gb);
1357 1358 1359

        s->mv_dir = MV_DIR_FORWARD;
        if ((cbpc & 16) == 0) {
1360 1361 1362 1363
            if (s->mcsel) {
                s->current_picture.mb_type[xy] = MB_TYPE_GMC   |
                                                 MB_TYPE_16x16 |
                                                 MB_TYPE_L0;
1364
                /* 16x16 global motion prediction */
1365
                s->mv_type     = MV_TYPE_16X16;
1366 1367
                mx             = get_amv(ctx, 0);
                my             = get_amv(ctx, 1);
1368 1369
                s->mv[0][0][0] = mx;
                s->mv[0][0][1] = my;
1370 1371 1372 1373
            } else if ((!s->progressive_sequence) && get_bits1(&s->gb)) {
                s->current_picture.mb_type[xy] = MB_TYPE_16x8 |
                                                 MB_TYPE_L0   |
                                                 MB_TYPE_INTERLACED;
1374
                /* 16x8 field motion prediction */
1375
                s->mv_type = MV_TYPE_FIELD;
1376

1377 1378
                s->field_select[0][0] = get_bits1(&s->gb);
                s->field_select[0][1] = get_bits1(&s->gb);
1379

1380
                ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
1381

1382
                for (i = 0; i < 2; i++) {
1383
                    mx = ff_h263_decode_motion(s, pred_x, s->f_code);
1384 1385 1386
                    if (mx >= 0xffff)
                        return -1;

1387
                    my = ff_h263_decode_motion(s, pred_y / 2, s->f_code);
1388 1389 1390 1391 1392 1393
                    if (my >= 0xffff)
                        return -1;

                    s->mv[0][i][0] = mx;
                    s->mv[0][i][1] = my;
                }
1394
            } else {
1395
                s->current_picture.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
1396 1397
                /* 16x16 motion prediction */
                s->mv_type = MV_TYPE_16X16;
1398 1399
                ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
                mx = ff_h263_decode_motion(s, pred_x, s->f_code);
1400 1401 1402 1403

                if (mx >= 0xffff)
                    return -1;

1404
                my = ff_h263_decode_motion(s, pred_y, s->f_code);
1405 1406 1407 1408 1409 1410 1411

                if (my >= 0xffff)
                    return -1;
                s->mv[0][0][0] = mx;
                s->mv[0][0][1] = my;
            }
        } else {
1412
            s->current_picture.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
1413 1414
            s->mv_type                     = MV_TYPE_8X8;
            for (i = 0; i < 4; i++) {
1415
                mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
1416
                mx      = ff_h263_decode_motion(s, pred_x, s->f_code);
1417 1418 1419
                if (mx >= 0xffff)
                    return -1;

1420
                my = ff_h263_decode_motion(s, pred_y, s->f_code);
1421 1422 1423 1424
                if (my >= 0xffff)
                    return -1;
                s->mv[0][i][0] = mx;
                s->mv[0][i][1] = my;
1425 1426
                mot_val[0]     = mx;
                mot_val[1]     = my;
1427 1428
            }
        }
1429 1430 1431
    } else if (s->pict_type == AV_PICTURE_TYPE_B) {
        int modb1;   // first bit of modb
        int modb2;   // second bit of modb
1432 1433
        int mb_type;

1434 1435
        s->mb_intra = 0;  // B-frames never contain intra blocks
        s->mcsel    = 0;  //      ...               true gmc blocks
1436

1437 1438 1439 1440 1441 1442
        if (s->mb_x == 0) {
            for (i = 0; i < 2; i++) {
                s->last_mv[i][0][0] =
                s->last_mv[i][0][1] =
                s->last_mv[i][1][0] =
                s->last_mv[i][1][1] = 0;
1443
            }
1444

1445
            ff_thread_await_progress(&s->next_picture_ptr->tf, s->mb_y, 0);
1446 1447 1448
        }

        /* if we skipped it in the future P Frame than skip it now too */
1449
        s->mb_skipped = s->next_picture.mbskip_table[s->mb_y * s->mb_stride + s->mb_x];  // Note, skiptab=0 if last was GMC
1450

1451 1452 1453
        if (s->mb_skipped) {
            /* skip mb */
            for (i = 0; i < 6; i++)
1454 1455
                s->block_last_index[i] = -1;

1456 1457 1458 1459 1460
            s->mv_dir      = MV_DIR_FORWARD;
            s->mv_type     = MV_TYPE_16X16;
            s->mv[0][0][0] =
            s->mv[0][0][1] =
            s->mv[1][0][0] =
1461
            s->mv[1][0][1] = 0;
1462 1463 1464
            s->current_picture.mb_type[xy] = MB_TYPE_SKIP  |
                                             MB_TYPE_16x16 |
                                             MB_TYPE_L0;
1465 1466 1467
            goto end;
        }

1468 1469 1470 1471 1472 1473 1474 1475 1476
        modb1 = get_bits1(&s->gb);
        if (modb1) {
            // like MB_TYPE_B_DIRECT but no vectors coded
            mb_type = MB_TYPE_DIRECT2 | MB_TYPE_SKIP | MB_TYPE_L0L1;
            cbp     = 0;
        } else {
            modb2   = get_bits1(&s->gb);
            mb_type = get_vlc2(&s->gb, mb_type_b_vlc.table, MB_TYPE_B_VLC_BITS, 1);
            if (mb_type < 0) {
1477 1478 1479
                av_log(s->avctx, AV_LOG_ERROR, "illegal MB_type\n");
                return -1;
            }
1480 1481 1482 1483
            mb_type = mb_type_b_map[mb_type];
            if (modb2) {
                cbp = 0;
            } else {
1484
                s->dsp.clear_blocks(s->block[0]);
1485
                cbp = get_bits(&s->gb, 6);
1486 1487 1488
            }

            if ((!IS_DIRECT(mb_type)) && cbp) {
1489 1490
                if (get_bits1(&s->gb))
                    ff_set_qscale(s, s->qscale + get_bits1(&s->gb) * 4 - 2);
1491 1492
            }

1493 1494 1495
            if (!s->progressive_sequence) {
                if (cbp)
                    s->interlaced_dct = get_bits1(&s->gb);
1496

1497
                if (!IS_DIRECT(mb_type) && get_bits1(&s->gb)) {
1498 1499 1500
                    mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
                    mb_type &= ~MB_TYPE_16x16;

1501 1502 1503
                    if (USES_LIST(mb_type, 0)) {
                        s->field_select[0][0] = get_bits1(&s->gb);
                        s->field_select[0][1] = get_bits1(&s->gb);
1504
                    }
1505 1506 1507
                    if (USES_LIST(mb_type, 1)) {
                        s->field_select[1][0] = get_bits1(&s->gb);
                        s->field_select[1][1] = get_bits1(&s->gb);
1508 1509 1510 1511 1512
                    }
                }
            }

            s->mv_dir = 0;
1513 1514
            if ((mb_type & (MB_TYPE_DIRECT2 | MB_TYPE_INTERLACED)) == 0) {
                s->mv_type = MV_TYPE_16X16;
1515

1516
                if (USES_LIST(mb_type, 0)) {
1517 1518
                    s->mv_dir = MV_DIR_FORWARD;

1519 1520
                    mx = ff_h263_decode_motion(s, s->last_mv[0][0][0], s->f_code);
                    my = ff_h263_decode_motion(s, s->last_mv[0][0][1], s->f_code);
1521 1522 1523 1524 1525 1526
                    s->last_mv[0][1][0] =
                    s->last_mv[0][0][0] =
                    s->mv[0][0][0]      = mx;
                    s->last_mv[0][1][1] =
                    s->last_mv[0][0][1] =
                    s->mv[0][0][1]      = my;
1527 1528
                }

1529
                if (USES_LIST(mb_type, 1)) {
1530 1531
                    s->mv_dir |= MV_DIR_BACKWARD;

1532 1533
                    mx = ff_h263_decode_motion(s, s->last_mv[1][0][0], s->b_code);
                    my = ff_h263_decode_motion(s, s->last_mv[1][0][1], s->b_code);
1534 1535 1536 1537 1538 1539
                    s->last_mv[1][1][0] =
                    s->last_mv[1][0][0] =
                    s->mv[1][0][0]      = mx;
                    s->last_mv[1][1][1] =
                    s->last_mv[1][0][1] =
                    s->mv[1][0][1]      = my;
1540
                }
1541 1542
            } else if (!IS_DIRECT(mb_type)) {
                s->mv_type = MV_TYPE_FIELD;
1543

1544
                if (USES_LIST(mb_type, 0)) {
1545 1546
                    s->mv_dir = MV_DIR_FORWARD;

1547 1548 1549 1550 1551 1552
                    for (i = 0; i < 2; i++) {
                        mx = ff_h263_decode_motion(s, s->last_mv[0][i][0], s->f_code);
                        my = ff_h263_decode_motion(s, s->last_mv[0][i][1] / 2, s->f_code);
                        s->last_mv[0][i][0] =
                        s->mv[0][i][0]      = mx;
                        s->last_mv[0][i][1] = (s->mv[0][i][1] = my) * 2;
1553 1554 1555
                    }
                }

1556
                if (USES_LIST(mb_type, 1)) {
1557 1558
                    s->mv_dir |= MV_DIR_BACKWARD;

1559 1560 1561 1562 1563 1564
                    for (i = 0; i < 2; i++) {
                        mx = ff_h263_decode_motion(s, s->last_mv[1][i][0], s->b_code);
                        my = ff_h263_decode_motion(s, s->last_mv[1][i][1] / 2, s->b_code);
                        s->last_mv[1][i][0] =
                        s->mv[1][i][0]      = mx;
                        s->last_mv[1][i][1] = (s->mv[1][i][1] = my) * 2;
1565 1566 1567 1568 1569
                    }
                }
            }
        }

1570 1571 1572 1573 1574
        if (IS_DIRECT(mb_type)) {
            if (IS_SKIP(mb_type)) {
                mx =
                my = 0;
            } else {
1575 1576
                mx = ff_h263_decode_motion(s, 0, 1);
                my = ff_h263_decode_motion(s, 0, 1);
1577 1578 1579
            }

            s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT;
1580
            mb_type  |= ff_mpeg4_set_direct_mv(s, mx, my);
1581
        }
1582
        s->current_picture.mb_type[xy] = mb_type;
1583
    } else { /* I-Frame */
1584
        do {
1585
            cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
1586 1587 1588
            if (cbpc < 0) {
                av_log(s->avctx, AV_LOG_ERROR,
                       "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
1589 1590
                return -1;
            }
1591
        } while (cbpc == 8);
1592 1593 1594

        dquant = cbpc & 4;
        s->mb_intra = 1;
1595

1596 1597
intra:
        s->ac_pred = get_bits1(&s->gb);
1598
        if (s->ac_pred)
1599
            s->current_picture.mb_type[xy] = MB_TYPE_INTRA | MB_TYPE_ACPRED;
1600
        else
1601
            s->current_picture.mb_type[xy] = MB_TYPE_INTRA;
1602

1603
        cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
1604 1605 1606
        if (cbpy < 0) {
            av_log(s->avctx, AV_LOG_ERROR,
                   "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
1607 1608 1609 1610
            return -1;
        }
        cbp = (cbpc & 3) | (cbpy << 2);

1611
        ctx->use_intra_dc_vlc = s->qscale < ctx->intra_dc_threshold;
1612

1613
        if (dquant)
1614 1615
            ff_set_qscale(s, s->qscale + quant_tab[get_bits(&s->gb, 2)]);

1616 1617
        if (!s->progressive_sequence)
            s->interlaced_dct = get_bits1(&s->gb);
1618 1619 1620 1621

        s->dsp.clear_blocks(s->block[0]);
        /* decode each block */
        for (i = 0; i < 6; i++) {
1622
            if (mpeg4_decode_block(ctx, block[i], i, cbp & 32, 1, 0) < 0)
1623
                return -1;
1624
            cbp += cbp;
1625 1626 1627 1628 1629 1630
        }
        goto end;
    }

    /* decode each block */
    for (i = 0; i < 6; i++) {
1631
        if (mpeg4_decode_block(ctx, block[i], i, cbp & 32, 0, 0) < 0)
1632
            return -1;
1633
        cbp += cbp;
1634 1635
    }

1636 1637 1638
end:
    /* per-MB end of slice check */
    if (s->codec_id == AV_CODEC_ID_MPEG4) {
1639
        int next = mpeg4_is_resync(ctx);
1640
        if (next) {
1641
            if        (s->mb_x + s->mb_y*s->mb_width + 1 >  next && (s->avctx->err_recognition & AV_EF_AGGRESSIVE)) {
1642 1643 1644
                return -1;
            } else if (s->mb_x + s->mb_y*s->mb_width + 1 >= next)
                return SLICE_END;
1645

1646
            if (s->pict_type == AV_PICTURE_TYPE_B) {
1647
                const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
1648
                ff_thread_await_progress(&s->next_picture_ptr->tf,
1649 1650 1651
                                         (s->mb_x + delta >= s->mb_width)
                                         ? FFMIN(s->mb_y + 1, s->mb_height - 1)
                                         : s->mb_y, 0);
1652
                if (s->next_picture.mbskip_table[xy + delta])
1653 1654 1655 1656
                    return SLICE_OK;
            }

            return SLICE_END;
1657 1658 1659 1660 1661 1662
        }
    }

    return SLICE_OK;
}

1663 1664
static int mpeg4_decode_gop_header(MpegEncContext *s, GetBitContext *gb)
{
1665 1666
    int hours, minutes, seconds;

1667
    if (!show_bits(gb, 23)) {
1668 1669 1670 1671
        av_log(s->avctx, AV_LOG_WARNING, "GOP header invalid\n");
        return -1;
    }

1672 1673
    hours   = get_bits(gb, 5);
    minutes = get_bits(gb, 6);
1674
    skip_bits1(gb);
1675
    seconds = get_bits(gb, 6);
1676

1677
    s->time_base = seconds + 60*(minutes + 60*hours);
1678 1679 1680 1681 1682 1683 1684

    skip_bits1(gb);
    skip_bits1(gb);

    return 0;
}

1685 1686
static int mpeg4_decode_profile_level(MpegEncContext *s, GetBitContext *gb)
{
1687

1688 1689
    s->avctx->profile = get_bits(gb, 4);
    s->avctx->level   = get_bits(gb, 4);
1690

1691 1692 1693 1694
    // for Simple profile, level 0
    if (s->avctx->profile == 0 && s->avctx->level == 8) {
        s->avctx->level = 0;
    }
1695

1696
    return 0;
1697 1698
}

1699
static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
1700
{
1701
    MpegEncContext *s = &ctx->m;
1702 1703 1704
    int width, height, vo_ver_id;

    /* vol header */
1705 1706 1707 1708 1709
    skip_bits(gb, 1);                   /* random access */
    s->vo_type = get_bits(gb, 8);
    if (get_bits1(gb) != 0) {           /* is_ol_id */
        vo_ver_id = get_bits(gb, 4);    /* vo_ver_id */
        skip_bits(gb, 3);               /* vo_priority */
1710 1711 1712
    } else {
        vo_ver_id = 1;
    }
1713 1714 1715 1716 1717 1718
    s->aspect_ratio_info = get_bits(gb, 4);
    if (s->aspect_ratio_info == FF_ASPECT_EXTENDED) {
        s->avctx->sample_aspect_ratio.num = get_bits(gb, 8);  // par_width
        s->avctx->sample_aspect_ratio.den = get_bits(gb, 8);  // par_height
    } else {
        s->avctx->sample_aspect_ratio = ff_h263_pixel_aspect[s->aspect_ratio_info];
1719 1720
    }

1721 1722 1723
    if ((s->vol_control_parameters = get_bits1(gb))) { /* vol control parameter */
        int chroma_format = get_bits(gb, 2);
        if (chroma_format != CHROMA_420)
1724
            av_log(s->avctx, AV_LOG_ERROR, "illegal chroma format\n");
1725 1726 1727

        s->low_delay = get_bits1(gb);
        if (get_bits1(gb)) {    /* vbv parameters */
1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739
            get_bits(gb, 15);   /* first_half_bitrate */
            skip_bits1(gb);     /* marker */
            get_bits(gb, 15);   /* latter_half_bitrate */
            skip_bits1(gb);     /* marker */
            get_bits(gb, 15);   /* first_half_vbv_buffer_size */
            skip_bits1(gb);     /* marker */
            get_bits(gb, 3);    /* latter_half_vbv_buffer_size */
            get_bits(gb, 11);   /* first_half_vbv_occupancy */
            skip_bits1(gb);     /* marker */
            get_bits(gb, 15);   /* latter_half_vbv_occupancy */
            skip_bits1(gb);     /* marker */
        }
1740 1741 1742 1743 1744
    } else {
        /* is setting low delay flag only once the smartest thing to do?
         * low delay detection won't be overriden. */
        if (s->picture_number == 0)
            s->low_delay = 0;
1745 1746
    }

1747 1748
    ctx->shape = get_bits(gb, 2); /* vol shape */
    if (ctx->shape != RECT_SHAPE)
1749
        av_log(s->avctx, AV_LOG_ERROR, "only rectangular vol supported\n");
1750
    if (ctx->shape == GRAY_SHAPE && vo_ver_id != 1) {
1751
        av_log(s->avctx, AV_LOG_ERROR, "Gray shape not supported\n");
1752
        skip_bits(gb, 4);  /* video_object_layer_shape_extension */
1753 1754 1755 1756 1757
    }

    check_marker(gb, "before time_increment_resolution");

    s->avctx->time_base.den = get_bits(gb, 16);
1758
    if (!s->avctx->time_base.den) {
1759
        av_log(s->avctx, AV_LOG_ERROR, "time_base.den==0\n");
1760
        s->avctx->time_base.num = 0;
1761 1762 1763
        return -1;
    }

1764 1765 1766
    ctx->time_increment_bits = av_log2(s->avctx->time_base.den - 1) + 1;
    if (ctx->time_increment_bits < 1)
        ctx->time_increment_bits = 1;
1767 1768 1769

    check_marker(gb, "before fixed_vop_rate");

1770
    if (get_bits1(gb) != 0)     /* fixed_vop_rate  */
1771
        s->avctx->time_base.num = get_bits(gb, ctx->time_increment_bits);
1772
    else
1773 1774
        s->avctx->time_base.num = 1;

1775
    ctx->t_frame = 0;
1776

1777 1778
    if (ctx->shape != BIN_ONLY_SHAPE) {
        if (ctx->shape == RECT_SHAPE) {
1779
            check_marker(gb, "before width");
1780
            width = get_bits(gb, 13);
1781
            check_marker(gb, "before height");
1782
            height = get_bits(gb, 13);
1783
            check_marker(gb, "after height");
1784 1785
            if (width && height &&  /* they should be non zero but who knows */
                !(s->width && s->codec_tag == AV_RL32("MP4S"))) {
1786 1787 1788
                if (s->width && s->height &&
                    (s->width != width || s->height != height))
                    s->context_reinit = 1;
1789
                s->width  = width;
1790 1791 1792 1793
                s->height = height;
            }
        }

1794 1795 1796 1797 1798 1799 1800
        s->progressive_sequence  =
        s->progressive_frame     = get_bits1(gb) ^ 1;
        s->interlaced_dct        = 0;
        if (!get_bits1(gb) && (s->avctx->debug & FF_DEBUG_PICT_INFO))
            av_log(s->avctx, AV_LOG_INFO,           /* OBMC Disable */
                   "MPEG4 OBMC not supported (very likely buggy encoder)\n");
        if (vo_ver_id == 1)
1801
            ctx->vol_sprite_usage = get_bits1(gb);    /* vol_sprite_usage */
1802
        else
1803
            ctx->vol_sprite_usage = get_bits(gb, 2);  /* vol_sprite_usage */
1804

1805
        if (ctx->vol_sprite_usage == STATIC_SPRITE)
1806
            av_log(s->avctx, AV_LOG_ERROR, "Static Sprites not supported\n");
1807 1808 1809
        if (ctx->vol_sprite_usage == STATIC_SPRITE ||
            ctx->vol_sprite_usage == GMC_SPRITE) {
            if (ctx->vol_sprite_usage == STATIC_SPRITE) {
1810
                skip_bits(gb, 13); // sprite_width
1811
                skip_bits1(gb); /* marker */
1812
                skip_bits(gb, 13); // sprite_height
1813
                skip_bits1(gb); /* marker */
1814
                skip_bits(gb, 13); // sprite_left
1815
                skip_bits1(gb); /* marker */
1816
                skip_bits(gb, 13); // sprite_top
1817 1818
                skip_bits1(gb); /* marker */
            }
1819 1820
            ctx->num_sprite_warping_points = get_bits(gb, 6);
            if (ctx->num_sprite_warping_points > 3) {
1821 1822
                av_log(s->avctx, AV_LOG_ERROR,
                       "%d sprite_warping_points\n",
1823 1824
                       ctx->num_sprite_warping_points);
                ctx->num_sprite_warping_points = 0;
1825 1826
                return -1;
            }
1827
            s->sprite_warping_accuracy  = get_bits(gb, 2);
1828
            ctx->sprite_brightness_change = get_bits1(gb);
1829
            if (ctx->vol_sprite_usage == STATIC_SPRITE)
1830
                skip_bits1(gb); // low_latency_sprite
1831 1832 1833
        }
        // FIXME sadct disable bit if verid!=1 && shape not rect

1834 1835 1836 1837 1838 1839 1840
        if (get_bits1(gb) == 1) {                   /* not_8_bit */
            s->quant_precision = get_bits(gb, 4);   /* quant_precision */
            if (get_bits(gb, 4) != 8)               /* bits_per_pixel */
                av_log(s->avctx, AV_LOG_ERROR, "N-bit not supported\n");
            if (s->quant_precision != 5)
                av_log(s->avctx, AV_LOG_ERROR,
                       "quant precision %d\n", s->quant_precision);
1841
            if (s->quant_precision<3 || s->quant_precision>9) {
1842 1843
                s->quant_precision = 5;
            }
1844 1845 1846 1847 1848 1849
        } else {
            s->quant_precision = 5;
        }

        // FIXME a bunch of grayscale shape things

1850
        if ((s->mpeg_quant = get_bits1(gb))) { /* vol_quant_type */
1851 1852 1853
            int i, v;

            /* load default matrixes */
1854 1855 1856 1857 1858 1859 1860 1861 1862
            for (i = 0; i < 64; i++) {
                int j = s->dsp.idct_permutation[i];
                v = ff_mpeg4_default_intra_matrix[i];
                s->intra_matrix[j]        = v;
                s->chroma_intra_matrix[j] = v;

                v = ff_mpeg4_default_non_intra_matrix[i];
                s->inter_matrix[j]        = v;
                s->chroma_inter_matrix[j] = v;
1863 1864 1865
            }

            /* load custom intra matrix */
1866 1867 1868
            if (get_bits1(gb)) {
                int last = 0;
                for (i = 0; i < 64; i++) {
1869
                    int j;
1870 1871 1872 1873 1874 1875 1876 1877
                    v = get_bits(gb, 8);
                    if (v == 0)
                        break;

                    last = v;
                    j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
                    s->intra_matrix[j]        = last;
                    s->chroma_intra_matrix[j] = last;
1878 1879 1880
                }

                /* replicate last value */
1881 1882 1883 1884
                for (; i < 64; i++) {
                    int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
                    s->intra_matrix[j]        = last;
                    s->chroma_intra_matrix[j] = last;
1885 1886 1887 1888
                }
            }

            /* load custom non intra matrix */
1889 1890 1891
            if (get_bits1(gb)) {
                int last = 0;
                for (i = 0; i < 64; i++) {
1892
                    int j;
1893 1894 1895 1896 1897 1898 1899 1900
                    v = get_bits(gb, 8);
                    if (v == 0)
                        break;

                    last = v;
                    j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
                    s->inter_matrix[j]        = v;
                    s->chroma_inter_matrix[j] = v;
1901 1902 1903
                }

                /* replicate last value */
1904 1905 1906 1907
                for (; i < 64; i++) {
                    int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
                    s->inter_matrix[j]        = last;
                    s->chroma_inter_matrix[j] = last;
1908 1909 1910 1911 1912 1913
                }
            }

            // FIXME a bunch of grayscale shape things
        }

1914 1915 1916 1917 1918
        if (vo_ver_id != 1)
            s->quarter_sample = get_bits1(gb);
        else
            s->quarter_sample = 0;

1919 1920 1921 1922 1923
        if (get_bits_left(gb) < 4) {
            av_log(s->avctx, AV_LOG_ERROR, "VOL Header truncated\n");
            return AVERROR_INVALIDDATA;
        }

1924 1925 1926 1927 1928
        if (!get_bits1(gb)) {
            int pos               = get_bits_count(gb);
            int estimation_method = get_bits(gb, 2);
            if (estimation_method < 2) {
                if (!get_bits1(gb)) {
1929 1930 1931 1932 1933 1934
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* opaque */
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* transparent */
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* intra_cae */
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* inter_cae */
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* no_update */
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* upampling */
1935
                }
1936
                if (!get_bits1(gb)) {
1937 1938 1939 1940
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* intra_blocks */
                    ctx->cplx_estimation_trash_p += 8 * get_bits1(gb);  /* inter_blocks */
                    ctx->cplx_estimation_trash_p += 8 * get_bits1(gb);  /* inter4v_blocks */
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* not coded blocks */
1941
                }
1942
                if (!check_marker(gb, "in complexity estimation part 1")) {
1943 1944 1945
                    skip_bits_long(gb, pos - get_bits_count(gb));
                    goto no_cplx_est;
                }
1946
                if (!get_bits1(gb)) {
1947 1948 1949 1950
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* dct_coeffs */
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* dct_lines */
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* vlc_syms */
                    ctx->cplx_estimation_trash_i += 4 * get_bits1(gb);  /* vlc_bits */
1951
                }
1952
                if (!get_bits1(gb)) {
1953 1954 1955 1956 1957 1958
                    ctx->cplx_estimation_trash_p += 8 * get_bits1(gb);  /* apm */
                    ctx->cplx_estimation_trash_p += 8 * get_bits1(gb);  /* npm */
                    ctx->cplx_estimation_trash_b += 8 * get_bits1(gb);  /* interpolate_mc_q */
                    ctx->cplx_estimation_trash_p += 8 * get_bits1(gb);  /* forwback_mc_q */
                    ctx->cplx_estimation_trash_p += 8 * get_bits1(gb);  /* halfpel2 */
                    ctx->cplx_estimation_trash_p += 8 * get_bits1(gb);  /* halfpel4 */
1959
                }
1960
                if (!check_marker(gb, "in complexity estimation part 2")) {
1961 1962 1963
                    skip_bits_long(gb, pos - get_bits_count(gb));
                    goto no_cplx_est;
                }
1964
                if (estimation_method == 1) {
1965 1966
                    ctx->cplx_estimation_trash_i += 8 * get_bits1(gb);  /* sadct */
                    ctx->cplx_estimation_trash_p += 8 * get_bits1(gb);  /* qpel */
1967
                }
1968 1969 1970 1971 1972 1973
            } else
                av_log(s->avctx, AV_LOG_ERROR,
                       "Invalid Complexity estimation method %d\n",
                       estimation_method);
        } else {

1974
no_cplx_est:
1975 1976 1977
            ctx->cplx_estimation_trash_i =
            ctx->cplx_estimation_trash_p =
            ctx->cplx_estimation_trash_b = 0;
1978 1979
        }

1980
        ctx->resync_marker = !get_bits1(gb); /* resync_marker_disabled */
1981

1982 1983
        s->data_partitioning = get_bits1(gb);
        if (s->data_partitioning)
1984
            ctx->rvlc = get_bits1(gb);
1985

1986
        if (vo_ver_id != 1) {
1987 1988
            ctx->new_pred = get_bits1(gb);
            if (ctx->new_pred) {
1989 1990
                av_log(s->avctx, AV_LOG_ERROR, "new pred not supported\n");
                skip_bits(gb, 2); /* requested upstream message type */
1991
                skip_bits1(gb);   /* newpred segment type */
1992
            }
1993
            if (get_bits1(gb)) // reduced_res_vop
1994 1995 1996
                av_log(s->avctx, AV_LOG_ERROR,
                       "reduced resolution VOP not supported\n");
        } else {
1997
            ctx->new_pred = 0;
1998 1999
        }

2000
        ctx->scalability = get_bits1(gb);
2001

2002
        if (ctx->scalability) {
2003
            GetBitContext bak = *gb;
2004 2005 2006 2007 2008
            int h_sampling_factor_n;
            int h_sampling_factor_m;
            int v_sampling_factor_n;
            int v_sampling_factor_m;

2009
            skip_bits1(gb);    // hierarchy_type
Mans Rullgard's avatar
Mans Rullgard committed
2010 2011
            skip_bits(gb, 4);  /* ref_layer_id */
            skip_bits1(gb);    /* ref_layer_sampling_dir */
2012 2013 2014 2015
            h_sampling_factor_n = get_bits(gb, 5);
            h_sampling_factor_m = get_bits(gb, 5);
            v_sampling_factor_n = get_bits(gb, 5);
            v_sampling_factor_m = get_bits(gb, 5);
2016
            ctx->enhancement_type = get_bits1(gb);
2017 2018 2019

            if (h_sampling_factor_n == 0 || h_sampling_factor_m == 0 ||
                v_sampling_factor_n == 0 || v_sampling_factor_m == 0) {
2020 2021
                /* illegal scalability header (VERY broken encoder),
                 * trying to workaround */
2022
                ctx->scalability = 0;
2023 2024
                *gb            = bak;
            } else
2025 2026 2027 2028 2029
                av_log(s->avctx, AV_LOG_ERROR, "scalability not supported\n");

            // bin shape stuff FIXME
        }
    }
2030

2031
    if (s->avctx->debug&FF_DEBUG_PICT_INFO) {
2032
        av_log(s->avctx, AV_LOG_DEBUG, "tb %d/%d, tincrbits:%d, qp_prec:%d, ps:%d,  %s%s%s%s\n",
2033
               s->avctx->time_base.num, s->avctx->time_base.den,
2034
               ctx->time_increment_bits,
2035 2036
               s->quant_precision,
               s->progressive_sequence,
2037
               ctx->scalability ? "scalability " :"" , s->quarter_sample ? "qpel " : "",
2038
               s->data_partitioning ? "partition " : "", ctx->rvlc ? "rvlc " : ""
2039 2040 2041
        );
    }

2042 2043 2044 2045
    return 0;
}

/**
2046
 * Decode the user data stuff in the header.
2047 2048
 * Also initializes divx/xvid/lavc_version/build.
 */
2049
static int decode_user_data(Mpeg4DecContext *ctx, GetBitContext *gb)
2050
{
2051
    MpegEncContext *s = &ctx->m;
2052 2053 2054 2055 2056 2057
    char buf[256];
    int i;
    int e;
    int ver = 0, build = 0, ver2 = 0, ver3 = 0;
    char last;

2058 2059 2060 2061
    for (i = 0; i < 255 && get_bits_count(gb) < gb->size_in_bits; i++) {
        if (show_bits(gb, 23) == 0)
            break;
        buf[i] = get_bits(gb, 8);
2062
    }
2063
    buf[i] = 0;
2064 2065

    /* divx detection */
2066 2067 2068 2069
    e = sscanf(buf, "DivX%dBuild%d%c", &ver, &build, &last);
    if (e < 2)
        e = sscanf(buf, "DivX%db%d%c", &ver, &build, &last);
    if (e >= 2) {
2070 2071
        ctx->divx_version = ver;
        ctx->divx_build   = build;
2072
        s->divx_packed  = e == 3 && last == 'p';
2073
        if (s->divx_packed && !ctx->showed_packed_warning) {
2074
            av_log(s->avctx, AV_LOG_INFO, "Video uses a non-standard and "
2075 2076
                   "wasteful way to store B-frames ('packed B-frames'). "
                   "Consider using a tool like VirtualDub or avidemux to fix it.\n");
2077
            ctx->showed_packed_warning = 1;
2078 2079 2080
        }
    }

2081
    /* libavcodec detection */
2082 2083 2084 2085 2086 2087 2088
    e = sscanf(buf, "FFmpe%*[^b]b%d", &build) + 3;
    if (e != 4)
        e = sscanf(buf, "FFmpeg v%d.%d.%d / libavcodec build: %d", &ver, &ver2, &ver3, &build);
    if (e != 4) {
        e = sscanf(buf, "Lavc%d.%d.%d", &ver, &ver2, &ver3) + 1;
        if (e > 1)
            build = (ver << 16) + (ver2 << 8) + ver3;
2089
    }
2090 2091
    if (e != 4) {
        if (strcmp(buf, "ffmpeg") == 0)
2092
            ctx->lavc_build = 4600;
2093
    }
2094
    if (e == 4)
2095
        ctx->lavc_build = build;
2096 2097

    /* Xvid detection */
2098 2099
    e = sscanf(buf, "XviD%d", &build);
    if (e == 1)
2100
        ctx->xvid_build = build;
2101 2102 2103 2104

    return 0;
}

2105 2106 2107 2108 2109
int ff_mpeg4_workaround_bugs(AVCodecContext *avctx)
{
    Mpeg4DecContext *ctx = avctx->priv_data;
    MpegEncContext *s = &ctx->m;

2110
    if (ctx->xvid_build == -1 && ctx->divx_version == -1 && ctx->lavc_build == -1) {
2111 2112 2113 2114 2115 2116
        if (s->stream_codec_tag == AV_RL32("XVID") ||
            s->codec_tag        == AV_RL32("XVID") ||
            s->codec_tag        == AV_RL32("XVIX") ||
            s->codec_tag        == AV_RL32("RMP4") ||
            s->codec_tag        == AV_RL32("ZMP4") ||
            s->codec_tag        == AV_RL32("SIPP"))
2117
            ctx->xvid_build = 0;
2118 2119
    }

2120
    if (ctx->xvid_build == -1 && ctx->divx_version == -1 && ctx->lavc_build == -1)
2121 2122
        if (s->codec_tag == AV_RL32("DIVX") && s->vo_type == 0 &&
            s->vol_control_parameters == 0)
2123
            ctx->divx_version = 400;  // divx 4
2124

2125 2126 2127
    if (ctx->xvid_build >= 0 && ctx->divx_version >= 0) {
        ctx->divx_version =
        ctx->divx_build   = -1;
2128 2129 2130 2131 2132 2133 2134 2135 2136
    }

    if (s->workaround_bugs & FF_BUG_AUTODETECT) {
        if (s->codec_tag == AV_RL32("XVIX"))
            s->workaround_bugs |= FF_BUG_XVID_ILACE;

        if (s->codec_tag == AV_RL32("UMP4"))
            s->workaround_bugs |= FF_BUG_UMP4;

2137
        if (ctx->divx_version >= 500 && ctx->divx_build < 1814)
2138 2139
            s->workaround_bugs |= FF_BUG_QPEL_CHROMA;

2140
        if (ctx->divx_version > 502 && ctx->divx_build < 1814)
2141 2142
            s->workaround_bugs |= FF_BUG_QPEL_CHROMA2;

2143
        if (ctx->xvid_build <= 3U)
2144 2145
            s->padding_bug_score = 256 * 256 * 256 * 64;

2146
        if (ctx->xvid_build <= 1U)
2147 2148
            s->workaround_bugs |= FF_BUG_QPEL_CHROMA;

2149
        if (ctx->xvid_build <= 12U)
2150 2151
            s->workaround_bugs |= FF_BUG_EDGE;

2152
        if (ctx->xvid_build <= 32U)
2153 2154 2155 2156 2157 2158 2159
            s->workaround_bugs |= FF_BUG_DC_CLIP;

#define SET_QPEL_FUNC(postfix1, postfix2)                           \
    s->dsp.put_        ## postfix1 = ff_put_        ## postfix2;    \
    s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;    \
    s->dsp.avg_        ## postfix1 = ff_avg_        ## postfix2;

2160
        if (ctx->lavc_build < 4653U)
2161 2162
            s->workaround_bugs |= FF_BUG_STD_QPEL;

2163
        if (ctx->lavc_build < 4655U)
2164 2165
            s->workaround_bugs |= FF_BUG_DIRECT_BLOCKSIZE;

2166
        if (ctx->lavc_build < 4670U)
2167 2168
            s->workaround_bugs |= FF_BUG_EDGE;

2169
        if (ctx->lavc_build <= 4712U)
2170 2171
            s->workaround_bugs |= FF_BUG_DC_CLIP;

2172
        if (ctx->divx_version >= 0)
2173
            s->workaround_bugs |= FF_BUG_DIRECT_BLOCKSIZE;
2174
        if (ctx->divx_version == 501 && ctx->divx_build == 20020416)
2175 2176
            s->padding_bug_score = 256 * 256 * 256 * 64;

2177
        if (ctx->divx_version < 500U)
2178 2179
            s->workaround_bugs |= FF_BUG_EDGE;

2180
        if (ctx->divx_version >= 0)
2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202
            s->workaround_bugs |= FF_BUG_HPEL_CHROMA;
    }

    if (s->workaround_bugs & FF_BUG_STD_QPEL) {
        SET_QPEL_FUNC(qpel_pixels_tab[0][5], qpel16_mc11_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[0][7], qpel16_mc31_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[0][9], qpel16_mc12_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)

        SET_QPEL_FUNC(qpel_pixels_tab[1][5], qpel8_mc11_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[1][7], qpel8_mc31_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[1][9], qpel8_mc12_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
        SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
    }

    if (avctx->debug & FF_DEBUG_BUGS)
        av_log(s->avctx, AV_LOG_DEBUG,
               "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
2203 2204
               s->workaround_bugs, ctx->lavc_build, ctx->xvid_build,
               ctx->divx_version, ctx->divx_build, s->divx_packed ? "p" : "");
2205 2206

#if HAVE_MMX
2207
    if (s->codec_id == AV_CODEC_ID_MPEG4 && ctx->xvid_build >= 0 &&
2208 2209 2210 2211 2212 2213 2214 2215 2216 2217
        avctx->idct_algo == FF_IDCT_AUTO &&
        (av_get_cpu_flags() & AV_CPU_FLAG_MMX)) {
        avctx->idct_algo = FF_IDCT_XVIDMMX;
        ff_dct_common_init(s);
        return 1;
    }
#endif
    return 0;
}

2218
static int decode_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb)
2219
{
2220
    MpegEncContext *s = &ctx->m;
2221
    int time_incr, time_increment;
2222
    int64_t pts;
2223

2224
    s->pict_type = get_bits(gb, 2) + AV_PICTURE_TYPE_I;        /* pict type: I = 0 , P = 1 */
2225 2226
    if (s->pict_type == AV_PICTURE_TYPE_B && s->low_delay &&
        s->vol_control_parameters == 0 && !(s->flags & CODEC_FLAG_LOW_DELAY)) {
2227
        av_log(s->avctx, AV_LOG_ERROR, "low_delay flag incorrectly, clearing it\n");
2228
        s->low_delay = 0;
2229 2230
    }

2231 2232 2233
    s->partitioned_frame = s->data_partitioning && s->pict_type != AV_PICTURE_TYPE_B;
    if (s->partitioned_frame)
        s->decode_mb = mpeg4_decode_partitioned_mb;
2234
    else
2235
        s->decode_mb = mpeg4_decode_mb;
2236

2237
    time_incr = 0;
2238 2239 2240 2241 2242
    while (get_bits1(gb) != 0)
        time_incr++;

    check_marker(gb, "before time_increment");

2243 2244
    if (ctx->time_increment_bits == 0 ||
        !(show_bits(gb, ctx->time_increment_bits + 1) & 1)) {
2245 2246 2247
        av_log(s->avctx, AV_LOG_ERROR,
               "hmm, seems the headers are not complete, trying to guess time_increment_bits\n");

2248 2249 2250
        for (ctx->time_increment_bits = 1;
             ctx->time_increment_bits < 16;
             ctx->time_increment_bits++) {
2251 2252
            if (s->pict_type == AV_PICTURE_TYPE_P ||
                (s->pict_type == AV_PICTURE_TYPE_S &&
2253
                 ctx->vol_sprite_usage == GMC_SPRITE)) {
2254
                if ((show_bits(gb, ctx->time_increment_bits + 6) & 0x37) == 0x30)
2255
                    break;
2256
            } else if ((show_bits(gb, ctx->time_increment_bits + 5) & 0x1F) == 0x18)
2257
                break;
2258 2259
        }

2260
        av_log(s->avctx, AV_LOG_ERROR,
2261
               "my guess is %d bits ;)\n", ctx->time_increment_bits);
2262 2263
        if (s->avctx->time_base.den && 4*s->avctx->time_base.den < 1<<ctx->time_increment_bits) {
            s->avctx->time_base.den = 1<<ctx->time_increment_bits;
2264
        }
2265 2266
    }

2267 2268 2269
    if (IS_3IV1)
        time_increment = get_bits1(gb);        // FIXME investigate further
    else
2270
        time_increment = get_bits(gb, ctx->time_increment_bits);
2271 2272 2273 2274 2275 2276 2277

    if (s->pict_type != AV_PICTURE_TYPE_B) {
        s->last_time_base = s->time_base;
        s->time_base     += time_incr;
        s->time = s->time_base * s->avctx->time_base.den + time_increment;
        if (s->workaround_bugs & FF_BUG_UMP4) {
            if (s->time < s->last_non_b_time) {
2278 2279 2280
                /* header is not mpeg-4-compatible, broken encoder,
                 * trying to workaround */
                s->time_base++;
2281
                s->time += s->avctx->time_base.den;
2282 2283
            }
        }
2284 2285 2286 2287 2288 2289 2290 2291
        s->pp_time         = s->time - s->last_non_b_time;
        s->last_non_b_time = s->time;
    } else {
        s->time    = (s->last_time_base + time_incr) * s->avctx->time_base.den + time_increment;
        s->pb_time = s->pp_time - (s->last_non_b_time - s->time);
        if (s->pp_time <= s->pb_time ||
            s->pp_time <= s->pp_time - s->pb_time ||
            s->pp_time <= 0) {
2292 2293 2294 2295 2296
            /* messed up order, maybe after seeking? skipping current b-frame */
            return FRAME_SKIPPED;
        }
        ff_mpeg4_init_direct_mv(s);

2297 2298 2299 2300 2301 2302 2303 2304
        if (ctx->t_frame == 0)
            ctx->t_frame = s->pb_time;
        if (ctx->t_frame == 0)
            ctx->t_frame = 1;  // 1/0 protection
        s->pp_field_time = (ROUNDED_DIV(s->last_non_b_time, ctx->t_frame) -
                            ROUNDED_DIV(s->last_non_b_time - s->pp_time, ctx->t_frame)) * 2;
        s->pb_field_time = (ROUNDED_DIV(s->time, ctx->t_frame) -
                            ROUNDED_DIV(s->last_non_b_time - s->pp_time, ctx->t_frame)) * 2;
2305 2306 2307 2308
        if (s->pp_field_time <= s->pb_field_time || s->pb_field_time <= 1) {
            s->pb_field_time = 2;
            s->pp_field_time = 4;
            if (!s->progressive_sequence)
2309 2310 2311 2312
                return FRAME_SKIPPED;
        }
    }

2313
    if (s->avctx->time_base.num)
2314
        pts = ROUNDED_DIV(s->time, s->avctx->time_base.num);
2315
    else
2316
        pts = AV_NOPTS_VALUE;
2317
    if (s->avctx->debug&FF_DEBUG_PTS)
2318
        av_log(s->avctx, AV_LOG_DEBUG, "MPEG4 PTS: %"PRId64"\n",
2319
               pts);
2320 2321 2322 2323

    check_marker(gb, "before vop_coded");

    /* vop coded */
2324 2325
    if (get_bits1(gb) != 1) {
        if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2326 2327 2328
            av_log(s->avctx, AV_LOG_ERROR, "vop not coded\n");
        return FRAME_SKIPPED;
    }
2329
    if (ctx->new_pred)
2330
        decode_new_pred(ctx, gb);
2331

2332
    if (ctx->shape != BIN_ONLY_SHAPE &&
2333 2334
                    (s->pict_type == AV_PICTURE_TYPE_P ||
                     (s->pict_type == AV_PICTURE_TYPE_S &&
2335
                      ctx->vol_sprite_usage == GMC_SPRITE))) {
2336 2337 2338 2339 2340
        /* rounding type for motion estimation */
        s->no_rounding = get_bits1(gb);
    } else {
        s->no_rounding = 0;
    }
2341 2342
    // FIXME reduced res stuff

2343
    if (ctx->shape != RECT_SHAPE) {
2344
        if (ctx->vol_sprite_usage != 1 || s->pict_type != AV_PICTURE_TYPE_I) {
2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360
            skip_bits(gb, 13);  /* width */
            skip_bits1(gb);     /* marker */
            skip_bits(gb, 13);  /* height */
            skip_bits1(gb);     /* marker */
            skip_bits(gb, 13);  /* hor_spat_ref */
            skip_bits1(gb);     /* marker */
            skip_bits(gb, 13);  /* ver_spat_ref */
        }
        skip_bits1(gb);         /* change_CR_disable */

        if (get_bits1(gb) != 0)
            skip_bits(gb, 8);   /* constant_alpha_value */
    }

    // FIXME complexity estimation stuff

2361
    if (ctx->shape != BIN_ONLY_SHAPE) {
2362
        skip_bits_long(gb, ctx->cplx_estimation_trash_i);
2363
        if (s->pict_type != AV_PICTURE_TYPE_I)
2364
            skip_bits_long(gb, ctx->cplx_estimation_trash_p);
2365
        if (s->pict_type == AV_PICTURE_TYPE_B)
2366
            skip_bits_long(gb, ctx->cplx_estimation_trash_b);
2367

2368 2369 2370 2371
        if (get_bits_left(gb) < 3) {
            av_log(s->avctx, AV_LOG_ERROR, "Header truncated\n");
            return -1;
        }
2372
        ctx->intra_dc_threshold = ff_mpeg4_dc_threshold[get_bits(gb, 3)];
2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392
        if (!s->progressive_sequence) {
            s->top_field_first = get_bits1(gb);
            s->alternate_scan  = get_bits1(gb);
        } else
            s->alternate_scan = 0;
    }

    if (s->alternate_scan) {
        ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable,   ff_alternate_vertical_scan);
        ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable,   ff_alternate_vertical_scan);
        ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_vertical_scan);
        ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
    } else {
        ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable,   ff_zigzag_direct);
        ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable,   ff_zigzag_direct);
        ff_init_scantable(s->dsp.idct_permutation, &s->intra_h_scantable, ff_alternate_horizontal_scan);
        ff_init_scantable(s->dsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
    }

    if (s->pict_type == AV_PICTURE_TYPE_S &&
2393 2394
        (ctx->vol_sprite_usage == STATIC_SPRITE ||
         ctx->vol_sprite_usage == GMC_SPRITE)) {
2395
        if (mpeg4_decode_sprite_trajectory(ctx, gb) < 0)
2396
            return AVERROR_INVALIDDATA;
2397
        if (ctx->sprite_brightness_change)
2398 2399
            av_log(s->avctx, AV_LOG_ERROR,
                   "sprite_brightness_change not supported\n");
2400
        if (ctx->vol_sprite_usage == STATIC_SPRITE)
2401 2402 2403
            av_log(s->avctx, AV_LOG_ERROR, "static sprite not supported\n");
    }

2404
    if (ctx->shape != BIN_ONLY_SHAPE) {
2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416
        s->chroma_qscale = s->qscale = get_bits(gb, s->quant_precision);
        if (s->qscale == 0) {
            av_log(s->avctx, AV_LOG_ERROR,
                   "Error, header damaged or not MPEG4 header (qscale=0)\n");
            return -1;  // makes no sense to continue, as there is nothing left from the image then
        }

        if (s->pict_type != AV_PICTURE_TYPE_I) {
            s->f_code = get_bits(gb, 3);        /* fcode_for */
            if (s->f_code == 0) {
                av_log(s->avctx, AV_LOG_ERROR,
                       "Error, header damaged or not MPEG4 header (f_code=0)\n");
2417
                s->f_code = 1;
2418 2419 2420 2421 2422 2423 2424
                return -1;  // makes no sense to continue, as there is nothing left from the image then
            }
        } else
            s->f_code = 1;

        if (s->pict_type == AV_PICTURE_TYPE_B) {
            s->b_code = get_bits(gb, 3);
2425 2426 2427 2428 2429 2430
            if (s->b_code == 0) {
                av_log(s->avctx, AV_LOG_ERROR,
                       "Error, header damaged or not MPEG4 header (b_code=0)\n");
                s->b_code=1;
                return -1; // makes no sense to continue, as the MV decoding will break very quickly
            }
2431 2432 2433 2434 2435
        } else
            s->b_code = 1;

        if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
            av_log(s->avctx, AV_LOG_DEBUG,
2436
                   "qp:%d fc:%d,%d %s size:%d pro:%d alt:%d top:%d %spel part:%d resync:%d w:%d a:%d rnd:%d vot:%d%s dc:%d ce:%d/%d/%d time:%"PRId64" tincr:%d\n",
2437 2438
                   s->qscale, s->f_code, s->b_code,
                   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")),
2439
                   gb->size_in_bits,s->progressive_sequence, s->alternate_scan,
2440
                   s->top_field_first, s->quarter_sample ? "q" : "h",
2441
                   s->data_partitioning, ctx->resync_marker,
2442
                   ctx->num_sprite_warping_points, s->sprite_warping_accuracy,
2443
                   1 - s->no_rounding, s->vo_type,
2444
                   s->vol_control_parameters ? " VOLC" : " ", ctx->intra_dc_threshold,
2445
                   ctx->cplx_estimation_trash_i, ctx->cplx_estimation_trash_p,
2446
                   ctx->cplx_estimation_trash_b,
2447 2448 2449
                   s->time,
                   time_increment
                  );
2450 2451
        }

2452
        if (!ctx->scalability) {
2453
            if (ctx->shape != RECT_SHAPE && s->pict_type != AV_PICTURE_TYPE_I)
2454 2455
                skip_bits1(gb);  // vop shape coding type
        } else {
2456
            if (ctx->enhancement_type) {
2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468
                int load_backward_shape = get_bits1(gb);
                if (load_backward_shape)
                    av_log(s->avctx, AV_LOG_ERROR,
                           "load backward shape isn't supported\n");
            }
            skip_bits(gb, 2);  // ref_select_code
        }
    }
    /* detect buggy encoders which don't set the low_delay flag
     * (divx4/xvid/opendivx). Note we cannot detect divx5 without b-frames
     * easily (although it's buggy too) */
    if (s->vo_type == 0 && s->vol_control_parameters == 0 &&
2469
        ctx->divx_version == -1 && s->picture_number == 0) {
2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485
        av_log(s->avctx, AV_LOG_WARNING,
               "looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
        s->low_delay = 1;
    }

    s->picture_number++;  // better than pic number==0 always ;)

    // FIXME add short header support
    s->y_dc_scale_table = ff_mpeg4_y_dc_scale_table;
    s->c_dc_scale_table = ff_mpeg4_c_dc_scale_table;

    if (s->workaround_bugs & FF_BUG_EDGE) {
        s->h_edge_pos = s->width;
        s->v_edge_pos = s->height;
    }
    return 0;
2486 2487 2488
}

/**
2489
 * Decode mpeg4 headers.
2490 2491 2492 2493
 * @return <0 if no VOP found (or a damaged one)
 *         FRAME_SKIPPED if a not coded VOP is found
 *         0 if a VOP is found
 */
2494
int ff_mpeg4_decode_picture_header(Mpeg4DecContext *ctx, GetBitContext *gb)
2495
{
2496
    MpegEncContext *s = &ctx->m;
2497
    unsigned startcode, v;
2498 2499 2500 2501

    /* search next start code */
    align_get_bits(gb);

2502
    if (s->codec_tag == AV_RL32("WV1F") && show_bits(gb, 24) == 0x575630) {
2503
        skip_bits(gb, 24);
2504
        if (get_bits(gb, 8) == 0xF0)
2505 2506 2507 2508
            goto end;
    }

    startcode = 0xff;
2509 2510 2511
    for (;;) {
        if (get_bits_count(gb) >= gb->size_in_bits) {
            if (gb->size_in_bits == 8 &&
2512
                (ctx->divx_version >= 0 || ctx->xvid_build >= 0) || s->codec_tag == AV_RL32("QMP4")) {
2513
                av_log(s->avctx, AV_LOG_VERBOSE, "frame skip %d\n", gb->size_in_bits);
2514 2515 2516
                return FRAME_SKIPPED;  // divx bug
            } else
                return -1;  // end of stream
2517 2518 2519 2520 2521 2522
        }

        /* use the bits after the test */
        v = get_bits(gb, 8);
        startcode = ((startcode << 8) | v) & 0xffffffff;

2523 2524
        if ((startcode & 0xFFFFFF00) != 0x100)
            continue;  // no startcode
2525

2526
        if (s->avctx->debug & FF_DEBUG_STARTCODE) {
2527
            av_log(s->avctx, AV_LOG_DEBUG, "startcode: %3X ", startcode);
2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581
            if (startcode <= 0x11F)
                av_log(s->avctx, AV_LOG_DEBUG, "Video Object Start");
            else if (startcode <= 0x12F)
                av_log(s->avctx, AV_LOG_DEBUG, "Video Object Layer Start");
            else if (startcode <= 0x13F)
                av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
            else if (startcode <= 0x15F)
                av_log(s->avctx, AV_LOG_DEBUG, "FGS bp start");
            else if (startcode <= 0x1AF)
                av_log(s->avctx, AV_LOG_DEBUG, "Reserved");
            else if (startcode == 0x1B0)
                av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq Start");
            else if (startcode == 0x1B1)
                av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Seq End");
            else if (startcode == 0x1B2)
                av_log(s->avctx, AV_LOG_DEBUG, "User Data");
            else if (startcode == 0x1B3)
                av_log(s->avctx, AV_LOG_DEBUG, "Group of VOP start");
            else if (startcode == 0x1B4)
                av_log(s->avctx, AV_LOG_DEBUG, "Video Session Error");
            else if (startcode == 0x1B5)
                av_log(s->avctx, AV_LOG_DEBUG, "Visual Object Start");
            else if (startcode == 0x1B6)
                av_log(s->avctx, AV_LOG_DEBUG, "Video Object Plane start");
            else if (startcode == 0x1B7)
                av_log(s->avctx, AV_LOG_DEBUG, "slice start");
            else if (startcode == 0x1B8)
                av_log(s->avctx, AV_LOG_DEBUG, "extension start");
            else if (startcode == 0x1B9)
                av_log(s->avctx, AV_LOG_DEBUG, "fgs start");
            else if (startcode == 0x1BA)
                av_log(s->avctx, AV_LOG_DEBUG, "FBA Object start");
            else if (startcode == 0x1BB)
                av_log(s->avctx, AV_LOG_DEBUG, "FBA Object Plane start");
            else if (startcode == 0x1BC)
                av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object start");
            else if (startcode == 0x1BD)
                av_log(s->avctx, AV_LOG_DEBUG, "Mesh Object Plane start");
            else if (startcode == 0x1BE)
                av_log(s->avctx, AV_LOG_DEBUG, "Still Texture Object start");
            else if (startcode == 0x1BF)
                av_log(s->avctx, AV_LOG_DEBUG, "Texture Spatial Layer start");
            else if (startcode == 0x1C0)
                av_log(s->avctx, AV_LOG_DEBUG, "Texture SNR Layer start");
            else if (startcode == 0x1C1)
                av_log(s->avctx, AV_LOG_DEBUG, "Texture Tile start");
            else if (startcode == 0x1C2)
                av_log(s->avctx, AV_LOG_DEBUG, "Texture Shape Layer start");
            else if (startcode == 0x1C3)
                av_log(s->avctx, AV_LOG_DEBUG, "stuffing start");
            else if (startcode <= 0x1C5)
                av_log(s->avctx, AV_LOG_DEBUG, "reserved");
            else if (startcode <= 0x1FF)
                av_log(s->avctx, AV_LOG_DEBUG, "System start");
2582 2583 2584
            av_log(s->avctx, AV_LOG_DEBUG, " at %d\n", get_bits_count(gb));
        }

2585
        if (startcode >= 0x120 && startcode <= 0x12F) {
2586
            if (decode_vol_header(ctx, gb) < 0)
2587
                return -1;
2588
        } else if (startcode == USER_DATA_STARTCODE) {
2589
            decode_user_data(ctx, gb);
2590
        } else if (startcode == GOP_STARTCODE) {
2591
            mpeg4_decode_gop_header(s, gb);
2592
        } else if (startcode == VOS_STARTCODE) {
2593
            mpeg4_decode_profile_level(s, gb);
2594
        } else if (startcode == VOP_STARTCODE) {
2595 2596 2597 2598 2599 2600
            break;
        }

        align_get_bits(gb);
        startcode = 0xff;
    }
2601

2602
end:
2603 2604 2605 2606
    if (s->flags & CODEC_FLAG_LOW_DELAY)
        s->low_delay = 1;
    s->avctx->has_b_frames = !s->low_delay;

2607
    return decode_vop_header(ctx, gb);
2608 2609
}

2610
av_cold void ff_mpeg4videodec_static_init(void) {
2611 2612 2613
    static int done = 0;

    if (!done) {
2614
        ff_init_rl(&ff_mpeg4_rl_intra, ff_mpeg4_static_rl_table_store[0]);
2615 2616
        ff_init_rl(&ff_rvlc_rl_inter, ff_mpeg4_static_rl_table_store[1]);
        ff_init_rl(&ff_rvlc_rl_intra, ff_mpeg4_static_rl_table_store[2]);
2617
        INIT_VLC_RL(ff_mpeg4_rl_intra, 554);
2618 2619
        INIT_VLC_RL(ff_rvlc_rl_inter, 1072);
        INIT_VLC_RL(ff_rvlc_rl_intra, 1072);
2620
        INIT_VLC_STATIC(&dc_lum, DC_VLC_BITS, 10 /* 13 */,
2621 2622
                        &ff_mpeg4_DCtab_lum[0][1], 2, 1,
                        &ff_mpeg4_DCtab_lum[0][0], 2, 1, 512);
2623
        INIT_VLC_STATIC(&dc_chrom, DC_VLC_BITS, 10 /* 13 */,
2624 2625
                        &ff_mpeg4_DCtab_chrom[0][1], 2, 1,
                        &ff_mpeg4_DCtab_chrom[0][0], 2, 1, 512);
2626
        INIT_VLC_STATIC(&sprite_trajectory, SPRITE_TRAJ_VLC_BITS, 15,
2627 2628
                        &ff_sprite_trajectory_tab[0][1], 4, 2,
                        &ff_sprite_trajectory_tab[0][0], 4, 2, 128);
2629
        INIT_VLC_STATIC(&mb_type_b_vlc, MB_TYPE_B_VLC_BITS, 4,
2630 2631
                        &ff_mb_type_b_tab[0][1], 2, 1,
                        &ff_mb_type_b_tab[0][0], 2, 1, 16);
2632
        done = 1;
2633
    }
2634 2635
}

2636 2637 2638 2639 2640
int ff_mpeg4_frame_end(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
{
    Mpeg4DecContext *ctx = avctx->priv_data;
    MpegEncContext    *s = &ctx->m;

2641 2642 2643
    /* divx 5.01+ bitstream reorder stuff */
    /* Since this clobbers the input buffer and hwaccel codecs still need the
     * data during hwaccel->end_frame we should not do this any earlier */
2644
    if (s->divx_packed) {
2645
        int current_pos     = s->gb.buffer == s->bitstream_buffer ? 0 : (get_bits_count(&s->gb) >> 3);
2646 2647
        int startcode_found = 0;

2648 2649
        if (buf_size - current_pos > 7) {

2650
            int i;
2651 2652
            for (i = current_pos; i < buf_size - 4; i++)

2653 2654 2655 2656
                if (buf[i]     == 0 &&
                    buf[i + 1] == 0 &&
                    buf[i + 2] == 1 &&
                    buf[i + 3] == 0xB6) {
2657
                    startcode_found = !(buf[i + 4] & 0x40);
2658 2659 2660 2661 2662
                    break;
                }
        }

        if (startcode_found) {
2663
            av_fast_padded_malloc(&s->bitstream_buffer,
2664
                           &s->allocated_bitstream_buffer_size,
2665
                           buf_size - current_pos);
2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676
            if (!s->bitstream_buffer)
                return AVERROR(ENOMEM);
            memcpy(s->bitstream_buffer, buf + current_pos,
                   buf_size - current_pos);
            s->bitstream_buffer_size = buf_size - current_pos;
        }
    }

    return 0;
}

2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687
static int mpeg4_update_thread_context(AVCodecContext *dst,
                                       const AVCodecContext *src)
{
    Mpeg4DecContext *s = dst->priv_data;
    const Mpeg4DecContext *s1 = src->priv_data;

    int ret = ff_mpeg_update_thread_context(dst, src);

    if (ret < 0)
        return ret;

2688
    memcpy(((uint8_t*)s) + sizeof(MpegEncContext), ((uint8_t*)s1) + sizeof(MpegEncContext), sizeof(Mpeg4DecContext) - sizeof(MpegEncContext));
2689

2690 2691 2692
    return 0;
}

2693 2694
static av_cold int decode_init(AVCodecContext *avctx)
{
2695 2696
    Mpeg4DecContext *ctx = avctx->priv_data;
    MpegEncContext *s = &ctx->m;
2697 2698
    int ret;

2699 2700 2701 2702
    ctx->divx_version =
    ctx->divx_build   =
    ctx->xvid_build   =
    ctx->lavc_build   = -1;
2703

2704
    if ((ret = ff_h263_decode_init(avctx)) < 0)
2705 2706 2707
        return ret;

    ff_mpeg4videodec_static_init();
2708 2709

    s->h263_pred = 1;
2710
    s->low_delay = 0; /* default, might be overridden in the vol header during header parsing */
2711
    s->decode_mb = mpeg4_decode_mb;
2712
    ctx->time_increment_bits = 4; /* default value for broken headers */
2713

2714
    avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
2715 2716
    avctx->internal->allocate_progress = 1;

2717 2718 2719
    return 0;
}

2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736
static const AVProfile mpeg4_video_profiles[] = {
    { FF_PROFILE_MPEG4_SIMPLE,                    "Simple Profile" },
    { FF_PROFILE_MPEG4_SIMPLE_SCALABLE,           "Simple Scalable Profile" },
    { FF_PROFILE_MPEG4_CORE,                      "Core Profile" },
    { FF_PROFILE_MPEG4_MAIN,                      "Main Profile" },
    { FF_PROFILE_MPEG4_N_BIT,                     "N-bit Profile" },
    { FF_PROFILE_MPEG4_SCALABLE_TEXTURE,          "Scalable Texture Profile" },
    { FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION,     "Simple Face Animation Profile" },
    { FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE,    "Basic Animated Texture Profile" },
    { FF_PROFILE_MPEG4_HYBRID,                    "Hybrid Profile" },
    { FF_PROFILE_MPEG4_ADVANCED_REAL_TIME,        "Advanced Real Time Simple Profile" },
    { FF_PROFILE_MPEG4_CORE_SCALABLE,             "Code Scalable Profile" },
    { FF_PROFILE_MPEG4_ADVANCED_CODING,           "Advanced Coding Profile" },
    { FF_PROFILE_MPEG4_ADVANCED_CORE,             "Advanced Core Profile" },
    { FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE, "Advanced Scalable Texture Profile" },
    { FF_PROFILE_MPEG4_SIMPLE_STUDIO,             "Simple Studio Profile" },
    { FF_PROFILE_MPEG4_ADVANCED_SIMPLE,           "Advanced Simple Profile" },
2737
    { FF_PROFILE_UNKNOWN },
2738 2739
};

2740
static const AVOption mpeg4_options[] = {
2741 2742
    {"quarter_sample", "1/4 subpel MC", offsetof(MpegEncContext, quarter_sample), FF_OPT_TYPE_INT, {.i64 = 0}, 0, 1, 0},
    {"divx_packed", "divx style packed b frames", offsetof(MpegEncContext, divx_packed), FF_OPT_TYPE_INT, {.i64 = 0}, 0, 1, 0},
2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759
    {NULL}
};

static const AVClass mpeg4_class = {
    "MPEG4 Video Decoder",
    av_default_item_name,
    mpeg4_options,
    LIBAVUTIL_VERSION_INT,
};

static const AVClass mpeg4_vdpau_class = {
    "MPEG4 Video VDPAU Decoder",
    av_default_item_name,
    mpeg4_options,
    LIBAVUTIL_VERSION_INT,
};

2760
AVCodec ff_mpeg4_decoder = {
2761
    .name                  = "mpeg4",
2762
    .long_name             = NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
2763
    .type                  = AVMEDIA_TYPE_VIDEO,
2764
    .id                    = AV_CODEC_ID_MPEG4,
2765
    .priv_data_size        = sizeof(Mpeg4DecContext),
2766 2767 2768 2769 2770 2771 2772
    .init                  = decode_init,
    .close                 = ff_h263_decode_end,
    .decode                = ff_h263_decode_frame,
    .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
                             CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
                             CODEC_CAP_FRAME_THREADS,
    .flush                 = ff_mpeg_flush,
2773
    .max_lowres            = 3,
2774
    .pix_fmts              = ff_h263_hwaccel_pixfmt_list_420,
2775
    .profiles              = NULL_IF_CONFIG_SMALL(mpeg4_video_profiles),
2776
    .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg4_update_thread_context),
2777
    .priv_class = &mpeg4_class,
2778 2779
};

2780 2781 2782 2783

#if CONFIG_MPEG4_VDPAU_DECODER
AVCodec ff_mpeg4_vdpau_decoder = {
    .name           = "mpeg4_vdpau",
2784
    .long_name      = NULL_IF_CONFIG_SMALL("MPEG-4 part 2 (VDPAU)"),
2785 2786 2787 2788 2789 2790 2791 2792
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_MPEG4,
    .priv_data_size = sizeof(MpegEncContext),
    .init           = decode_init,
    .close          = ff_h263_decode_end,
    .decode         = ff_h263_decode_frame,
    .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
                      CODEC_CAP_HWACCEL_VDPAU,
2793
    .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_VDPAU_MPEG4,
2794 2795 2796 2797
                                                  AV_PIX_FMT_NONE },
    .priv_class     = &mpeg4_vdpau_class,
};
#endif