loco.c 9.96 KB
Newer Older
1 2 3 4
/*
 * LOCO codec
 * Copyright (c) 2005 Konstantin Shishkov
 *
5 6 7
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
8 9
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
13 14 15 16 17
 * 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
18
 * License along with FFmpeg; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21

22
/**
23
 * @file
24 25
 * LOCO codec.
 */
26

27
#include "avcodec.h"
28
#include "get_bits.h"
29
#include "golomb.h"
30
#include "internal.h"
31
#include "mathops.h"
32

33 34 35 36 37 38 39 40 41 42 43 44
enum LOCO_MODE {
    LOCO_UNKN  =  0,
    LOCO_CYUY2 = -1,
    LOCO_CRGB  = -2,
    LOCO_CRGBA = -3,
    LOCO_CYV12 = -4,
    LOCO_YUY2  =  1,
    LOCO_UYVY  =  2,
    LOCO_RGB   =  3,
    LOCO_RGBA  =  4,
    LOCO_YV12  =  5,
};
45

46
typedef struct LOCOContext {
47 48
    AVCodecContext *avctx;
    int lossy;
49
    enum LOCO_MODE mode;
50 51
} LOCOContext;

52
typedef struct RICEContext {
53 54 55
    GetBitContext gb;
    int save, run, run2; /* internal rice decoder state */
    int sum, count; /* sum and count for getting rice parameter */
56
    int lossy;
57
} RICEContext;
58 59 60 61 62

static int loco_get_rice_param(RICEContext *r)
{
    int cnt = 0;
    int val = r->count;
63

64
    while (r->sum > val && cnt < 9) {
65 66 67
        val <<= 1;
        cnt++;
    }
68

69 70 71 72 73 74 75
    return cnt;
}

static inline void loco_update_rice_param(RICEContext *r, int val)
{
    r->sum += val;
    r->count++;
76

77 78
    if (r->count == 16) {
        r->sum   >>= 1;
79 80 81 82 83 84 85 86 87
        r->count >>= 1;
    }
}

static inline int loco_get_rice(RICEContext *r)
{
    int v;
    if (r->run > 0) { /* we have zero run */
        r->run--;
88
        loco_update_rice_param(r, 0);
89 90
        return 0;
    }
91
    v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
92
    loco_update_rice_param(r, (v + 1) >> 1);
93 94
    if (!v) {
        if (r->save >= 0) {
95
            r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
96
            if (r->run > 1)
97 98 99
                r->save += r->run + 1;
            else
                r->save -= 3;
100
        } else
101
            r->run2++;
102
    } else {
103
        v = ((v >> 1) + r->lossy) ^ -(v & 1);
104 105 106 107 108 109 110
        if (r->run2 > 0) {
            if (r->run2 > 2)
                r->save += r->run2;
            else
                r->save -= 3;
            r->run2 = 0;
        }
111
    }
112

113 114 115 116 117 118 119
    return v;
}

/* LOCO main predictor - LOCO-I/JPEG-LS predictor */
static inline int loco_predict(uint8_t* data, int stride, int step)
{
    int a, b, c;
120

121 122 123
    a = data[-stride];
    b = data[-step];
    c = data[-stride - step];
124

125
    return mid_pred(a, a + b - c, b);
126 127 128
}

static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
Michael Niedermayer's avatar
Michael Niedermayer committed
129
                             int stride, const uint8_t *buf, int buf_size, int step)
130 131 132
{
    RICEContext rc;
    int val;
133
    int ret;
134
    int i, j;
135

136 137 138
    if(buf_size<=0)
        return -1;

139 140 141
    if ((ret = init_get_bits8(&rc.gb, buf, buf_size)) < 0)
        return ret;

142 143 144
    rc.save  = 0;
    rc.run   = 0;
    rc.run2  = 0;
145 146
    rc.lossy = l->lossy;

147
    rc.sum   = 8;
148
    rc.count = 1;
149

150
    /* restore top left pixel */
151
    val     = loco_get_rice(&rc);
152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169
    data[0] = 128 + val;
    /* restore top line */
    for (i = 1; i < width; i++) {
        val = loco_get_rice(&rc);
        data[i * step] = data[i * step - step] + val;
    }
    data += stride;
    for (j = 1; j < height; j++) {
        /* restore left column */
        val = loco_get_rice(&rc);
        data[0] = data[-stride] + val;
        /* restore all other pixels */
        for (i = 1; i < width; i++) {
            val = loco_get_rice(&rc);
            data[i * step] = loco_predict(&data[i * step], stride, step) + val;
        }
        data += stride;
    }
170

171
    return (get_bits_count(&rc.gb) + 7) >> 3;
172 173
}

174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190
static void rotate_faulty_loco(uint8_t *data, int width, int height, int stride, int step)
{
    int y;

    for (y=1; y<height; y++) {
        if (width>=y) {
            memmove(data + y*stride,
                    data + y*(stride + step),
                    step*(width-y));
            if (y+1 < height)
                memmove(data + y*stride + step*(width-y),
                        data + (y+1)*stride,
                        step*y);
        }
    }
}

191
static int decode_frame(AVCodecContext *avctx,
192
                        void *data, int *got_frame,
193
                        AVPacket *avpkt)
194 195
{
    LOCOContext * const l = avctx->priv_data;
196 197
    const uint8_t *buf    = avpkt->data;
    int buf_size          = avpkt->size;
198
    AVFrame * const p     = data;
199
    int decoded, ret;
200

201
    if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
202
        return ret;
203 204
    p->key_frame = 1;

205
#define ADVANCE_BY_DECODED do { \
206
    if (decoded < 0 || decoded >= buf_size) goto buf_too_small; \
207 208
    buf += decoded; buf_size -= decoded; \
} while(0)
209 210 211 212
    switch(l->mode) {
    case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
        decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
                                    p->linesize[0], buf, buf_size, 1);
213
        ADVANCE_BY_DECODED;
214 215
        decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
                                    p->linesize[1], buf, buf_size, 1);
216
        ADVANCE_BY_DECODED;
217 218 219 220 221 222
        decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
                                    p->linesize[2], buf, buf_size, 1);
        break;
    case LOCO_CYV12: case LOCO_YV12:
        decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
                                    p->linesize[0], buf, buf_size, 1);
223
        ADVANCE_BY_DECODED;
224 225
        decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
                                    p->linesize[2], buf, buf_size, 1);
226
        ADVANCE_BY_DECODED;
227 228
        decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
                                    p->linesize[1], buf, buf_size, 1);
229 230
        break;
    case LOCO_CRGB: case LOCO_RGB:
231 232
        decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
                                    -p->linesize[0], buf, buf_size, 3);
233
        ADVANCE_BY_DECODED;
234 235
        decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
                                    -p->linesize[0], buf, buf_size, 3);
236
        ADVANCE_BY_DECODED;
237 238
        decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
                                    -p->linesize[0], buf, buf_size, 3);
239 240
        if (avctx->width & 1)
            rotate_faulty_loco(p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height, -p->linesize[0], 3);
241
        break;
242
    case LOCO_CRGBA:
243
    case LOCO_RGBA:
Michael Niedermayer's avatar
Michael Niedermayer committed
244 245
        decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
                                    -p->linesize[0], buf, buf_size, 4);
246
        ADVANCE_BY_DECODED;
Michael Niedermayer's avatar
Michael Niedermayer committed
247 248
        decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
                                    -p->linesize[0], buf, buf_size, 4);
249
        ADVANCE_BY_DECODED;
Michael Niedermayer's avatar
Michael Niedermayer committed
250 251
        decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
                                    -p->linesize[0], buf, buf_size, 4);
252
        ADVANCE_BY_DECODED;
Michael Niedermayer's avatar
Michael Niedermayer committed
253 254
        decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 3, avctx->width, avctx->height,
                                    -p->linesize[0], buf, buf_size, 4);
255
        break;
256 257
    default:
        av_assert0(0);
258 259
    }

260 261 262 263
    if (decoded < 0 || decoded > buf_size)
        goto buf_too_small;
    buf_size -= decoded;

264
    *got_frame      = 1;
265

266
    return avpkt->size - buf_size;
267 268 269
buf_too_small:
    av_log(avctx, AV_LOG_ERROR, "Input data too small.\n");
    return AVERROR(EINVAL);
270 271
}

272 273
static av_cold int decode_init(AVCodecContext *avctx)
{
274 275 276 277 278 279 280
    LOCOContext * const l = avctx->priv_data;
    int version;

    l->avctx = avctx;
    if (avctx->extradata_size < 12) {
        av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
               avctx->extradata_size);
281
        return AVERROR_INVALIDDATA;
282
    }
283
    version = AV_RL32(avctx->extradata);
284
    switch (version) {
285 286 287 288
    case 1:
        l->lossy = 0;
        break;
    case 2:
289
        l->lossy = AV_RL32(avctx->extradata + 8);
290 291
        break;
    default:
292
        l->lossy = AV_RL32(avctx->extradata + 8);
293
        avpriv_request_sample(avctx, "LOCO codec version %i", version);
294
    }
295

296
    l->mode = AV_RL32(avctx->extradata + 4);
297 298 299 300
    switch (l->mode) {
    case LOCO_CYUY2:
    case LOCO_YUY2:
    case LOCO_UYVY:
301
        avctx->pix_fmt = AV_PIX_FMT_YUV422P;
302
        break;
303 304
    case LOCO_CRGB:
    case LOCO_RGB:
305
        avctx->pix_fmt = AV_PIX_FMT_BGR24;
306
        break;
307 308
    case LOCO_CYV12:
    case LOCO_YV12:
309
        avctx->pix_fmt = AV_PIX_FMT_YUV420P;
310
        break;
311 312
    case LOCO_CRGBA:
    case LOCO_RGBA:
313
        avctx->pix_fmt = AV_PIX_FMT_BGRA;
314 315 316
        break;
    default:
        av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
317
        return AVERROR_INVALIDDATA;
318
    }
319
    if (avctx->debug & FF_DEBUG_PICT_INFO)
320
        av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
321

322 323 324
    return 0;
}

325
AVCodec ff_loco_decoder = {
326
    .name           = "loco",
327
    .long_name      = NULL_IF_CONFIG_SMALL("LOCO"),
328
    .type           = AVMEDIA_TYPE_VIDEO,
329
    .id             = AV_CODEC_ID_LOCO,
330 331 332 333
    .priv_data_size = sizeof(LOCOContext),
    .init           = decode_init,
    .decode         = decode_frame,
    .capabilities   = CODEC_CAP_DR1,
334
};