git.sesse.net Git - ffmpeg/blob - libavcodec/cinepak.c

   1 /*
   2  * Cinepak Video Decoder
   3  * Copyright (C) 2003 the ffmpeg project
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * 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  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; 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  * Cinepak video decoder
  25  * @author Ewald Snel <ewald@rambo.its.tudelft.nl>
  26  *
  27  * @see For more information on the Cinepak algorithm, visit:
  28  *   http://www.csse.monash.edu.au/~timf/
  29  * @see For more information on the quirky data inside Sega FILM/CPK files, visit:
  30  *   http://wiki.multimedia.cx/index.php?title=Sega_FILM
  31  */
  32
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36
  37 #include "libavutil/common.h"
  38 #include "libavutil/intreadwrite.h"
  39 #include "avcodec.h"
  40
  41
  42 typedef struct {
  43     uint8_t  y0, y1, y2, y3;
  44     uint8_t  u, v;
  45 } cvid_codebook;
  46
  47 #define MAX_STRIPS      32
  48
  49 typedef struct {
  50     uint16_t          id;
  51     uint16_t          x1, y1;
  52     uint16_t          x2, y2;
  53     cvid_codebook     v4_codebook[256];
  54     cvid_codebook     v1_codebook[256];
  55 } cvid_strip;
  56
  57 typedef struct CinepakContext {
  58
  59     AVCodecContext *avctx;
  60     AVFrame frame;
  61
  62     const unsigned char *data;
  63     int size;
  64
  65     int width, height;
  66
  67     int palette_video;
  68     cvid_strip strips[MAX_STRIPS];
  69
  70     int sega_film_skip_bytes;
  71
  72     uint32_t pal[256];
  73 } CinepakContext;
  74
  75 static void cinepak_decode_codebook (cvid_codebook *codebook,
  76                                      int chunk_id, int size, const uint8_t *data)
  77 {
  78     const uint8_t *eod = (data + size);
  79     uint32_t flag, mask;
  80     int      i, n;
  81
  82     /* check if this chunk contains 4- or 6-element vectors */
  83     n    = (chunk_id & 0x04) ? 4 : 6;
  84     flag = 0;
  85     mask = 0;
  86
  87     for (i=0; i < 256; i++) {
  88         if ((chunk_id & 0x01) && !(mask >>= 1)) {
  89             if ((data + 4) > eod)
  90                 break;
  91
  92             flag  = AV_RB32 (data);
  93             data += 4;
  94             mask  = 0x80000000;
  95         }
  96
  97         if (!(chunk_id & 0x01) || (flag & mask)) {
  98             if ((data + n) > eod)
  99                 break;
 100
 101             if (n == 6) {
 102                 codebook[i].y0 = *data++;
 103                 codebook[i].y1 = *data++;
 104                 codebook[i].y2 = *data++;
 105                 codebook[i].y3 = *data++;
 106                 codebook[i].u  = 128 + *data++;
 107                 codebook[i].v  = 128 + *data++;
 108             } else {
 109                 /* this codebook type indicates either greyscale or
 110                  * palettized video; if palettized, U & V components will
 111                  * not be used so it is safe to set them to 128 for the
 112                  * benefit of greyscale rendering in YUV420P */
 113                 codebook[i].y0 = *data++;
 114                 codebook[i].y1 = *data++;
 115                 codebook[i].y2 = *data++;
 116                 codebook[i].y3 = *data++;
 117                 codebook[i].u  = 128;
 118                 codebook[i].v  = 128;
 119             }
 120         }
 121     }
 122 }
 123
 124 static int cinepak_decode_vectors (CinepakContext *s, cvid_strip *strip,
 125                                    int chunk_id, int size, const uint8_t *data)
 126 {
 127     const uint8_t   *eod = (data + size);
 128     uint32_t         flag, mask;
 129     cvid_codebook   *codebook;
 130     unsigned int     x, y;
 131     uint32_t         iy[4];
 132     uint32_t         iu[2];
 133     uint32_t         iv[2];
 134
 135     flag = 0;
 136     mask = 0;
 137
 138     for (y=strip->y1; y < strip->y2; y+=4) {
 139
 140         iy[0] = strip->x1 + (y * s->frame.linesize[0]);
 141         iy[1] = iy[0] + s->frame.linesize[0];
 142         iy[2] = iy[1] + s->frame.linesize[0];
 143         iy[3] = iy[2] + s->frame.linesize[0];
 144         iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]);
 145         iu[1] = iu[0] + s->frame.linesize[1];
 146         iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]);
 147         iv[1] = iv[0] + s->frame.linesize[2];
 148
 149         for (x=strip->x1; x < strip->x2; x+=4) {
 150             if ((chunk_id & 0x01) && !(mask >>= 1)) {
 151                 if ((data + 4) > eod)
 152                     return AVERROR_INVALIDDATA;
 153
 154                 flag  = AV_RB32 (data);
 155                 data += 4;
 156                 mask  = 0x80000000;
 157             }
 158
 159             if (!(chunk_id & 0x01) || (flag & mask)) {
 160                 if (!(chunk_id & 0x02) && !(mask >>= 1)) {
 161                     if ((data + 4) > eod)
 162                         return AVERROR_INVALIDDATA;
 163
 164                     flag  = AV_RB32 (data);
 165                     data += 4;
 166                     mask  = 0x80000000;
 167                 }
 168
 169                 if ((chunk_id & 0x02) || (~flag & mask)) {
 170                     if (data >= eod)
 171                         return AVERROR_INVALIDDATA;
 172
 173                     codebook = &strip->v1_codebook[*data++];
 174                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 175                     s->frame.data[0][iy[0] + 1] = codebook->y0;
 176                     s->frame.data[0][iy[1] + 0] = codebook->y0;
 177                     s->frame.data[0][iy[1] + 1] = codebook->y0;
 178                     if (!s->palette_video) {
 179                         s->frame.data[1][iu[0]] = codebook->u;
 180                         s->frame.data[2][iv[0]] = codebook->v;
 181                     }
 182
 183                     s->frame.data[0][iy[0] + 2] = codebook->y1;
 184                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 185                     s->frame.data[0][iy[1] + 2] = codebook->y1;
 186                     s->frame.data[0][iy[1] + 3] = codebook->y1;
 187                     if (!s->palette_video) {
 188                         s->frame.data[1][iu[0] + 1] = codebook->u;
 189                         s->frame.data[2][iv[0] + 1] = codebook->v;
 190                     }
 191
 192                     s->frame.data[0][iy[2] + 0] = codebook->y2;
 193                     s->frame.data[0][iy[2] + 1] = codebook->y2;
 194                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 195                     s->frame.data[0][iy[3] + 1] = codebook->y2;
 196                     if (!s->palette_video) {
 197                         s->frame.data[1][iu[1]] = codebook->u;
 198                         s->frame.data[2][iv[1]] = codebook->v;
 199                     }
 200
 201                     s->frame.data[0][iy[2] + 2] = codebook->y3;
 202                     s->frame.data[0][iy[2] + 3] = codebook->y3;
 203                     s->frame.data[0][iy[3] + 2] = codebook->y3;
 204                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 205                     if (!s->palette_video) {
 206                         s->frame.data[1][iu[1] + 1] = codebook->u;
 207                         s->frame.data[2][iv[1] + 1] = codebook->v;
 208                     }
 209
 210                 } else if (flag & mask) {
 211                     if ((data + 4) > eod)
 212                         return AVERROR_INVALIDDATA;
 213
 214                     codebook = &strip->v4_codebook[*data++];
 215                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 216                     s->frame.data[0][iy[0] + 1] = codebook->y1;
 217                     s->frame.data[0][iy[1] + 0] = codebook->y2;
 218                     s->frame.data[0][iy[1] + 1] = codebook->y3;
 219                     if (!s->palette_video) {
 220                         s->frame.data[1][iu[0]] = codebook->u;
 221                         s->frame.data[2][iv[0]] = codebook->v;
 222                     }
 223
 224                     codebook = &strip->v4_codebook[*data++];
 225                     s->frame.data[0][iy[0] + 2] = codebook->y0;
 226                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 227                     s->frame.data[0][iy[1] + 2] = codebook->y2;
 228                     s->frame.data[0][iy[1] + 3] = codebook->y3;
 229                     if (!s->palette_video) {
 230                         s->frame.data[1][iu[0] + 1] = codebook->u;
 231                         s->frame.data[2][iv[0] + 1] = codebook->v;
 232                     }
 233
 234                     codebook = &strip->v4_codebook[*data++];
 235                     s->frame.data[0][iy[2] + 0] = codebook->y0;
 236                     s->frame.data[0][iy[2] + 1] = codebook->y1;
 237                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 238                     s->frame.data[0][iy[3] + 1] = codebook->y3;
 239                     if (!s->palette_video) {
 240                         s->frame.data[1][iu[1]] = codebook->u;
 241                         s->frame.data[2][iv[1]] = codebook->v;
 242                     }
 243
 244                     codebook = &strip->v4_codebook[*data++];
 245                     s->frame.data[0][iy[2] + 2] = codebook->y0;
 246                     s->frame.data[0][iy[2] + 3] = codebook->y1;
 247                     s->frame.data[0][iy[3] + 2] = codebook->y2;
 248                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 249                     if (!s->palette_video) {
 250                         s->frame.data[1][iu[1] + 1] = codebook->u;
 251                         s->frame.data[2][iv[1] + 1] = codebook->v;
 252                     }
 253
 254                 }
 255             }
 256
 257             iy[0] += 4;  iy[1] += 4;
 258             iy[2] += 4;  iy[3] += 4;
 259             iu[0] += 2;  iu[1] += 2;
 260             iv[0] += 2;  iv[1] += 2;
 261         }
 262     }
 263
 264     return 0;
 265 }
 266
 267 static int cinepak_decode_strip (CinepakContext *s,
 268                                  cvid_strip *strip, const uint8_t *data, int size)
 269 {
 270     const uint8_t *eod = (data + size);
 271     int      chunk_id, chunk_size;
 272
 273     /* coordinate sanity checks */
 274     if (strip->x2 > s->width   ||
 275         strip->y2 > s->height  ||
 276         strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
 277         return AVERROR_INVALIDDATA;
 278
 279     while ((data + 4) <= eod) {
 280         chunk_id   = data[0];
 281         chunk_size = AV_RB24 (&data[1]) - 4;
 282         if(chunk_size < 0)
 283             return AVERROR_INVALIDDATA;
 284
 285         data      += 4;
 286         chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
 287
 288         switch (chunk_id) {
 289
 290         case 0x20:
 291         case 0x21:
 292         case 0x24:
 293         case 0x25:
 294             cinepak_decode_codebook (strip->v4_codebook, chunk_id,
 295                 chunk_size, data);
 296             break;
 297
 298         case 0x22:
 299         case 0x23:
 300         case 0x26:
 301         case 0x27:
 302             cinepak_decode_codebook (strip->v1_codebook, chunk_id,
 303                 chunk_size, data);
 304             break;
 305
 306         case 0x30:
 307         case 0x31:
 308         case 0x32:
 309             return cinepak_decode_vectors (s, strip, chunk_id,
 310                 chunk_size, data);
 311         }
 312
 313         data += chunk_size;
 314     }
 315
 316     return AVERROR_INVALIDDATA;
 317 }
 318
 319 static int cinepak_decode (CinepakContext *s)
 320 {
 321     const uint8_t  *eod = (s->data + s->size);
 322     int           i, result, strip_size, frame_flags, num_strips;
 323     int           y0 = 0;
 324     int           encoded_buf_size;
 325
 326     if (s->size < 10)
 327         return AVERROR_INVALIDDATA;
 328
 329     frame_flags = s->data[0];
 330     num_strips  = AV_RB16 (&s->data[8]);
 331     encoded_buf_size = AV_RB24(&s->data[1]);
 332
 333     /* if this is the first frame, check for deviant Sega FILM data */
 334     if (s->sega_film_skip_bytes == -1) {
 335         if (!encoded_buf_size) {
 336             av_log_ask_for_sample(s->avctx, "encoded_buf_size is 0");
 337             return AVERROR_INVALIDDATA;
 338         }
 339         if (encoded_buf_size != s->size && (s->size % encoded_buf_size) != 0) {
 340             /* If the encoded frame size differs from the frame size as indicated
 341              * by the container file, this data likely comes from a Sega FILM/CPK file.
 342              * If the frame header is followed by the bytes FE 00 00 06 00 00 then
 343              * this is probably one of the two known files that have 6 extra bytes
 344              * after the frame header. Else, assume 2 extra bytes. The container
 345              * size also cannot be a multiple of the encoded size. */
 346             if (s->size >= 16 &&
 347                 (s->data[10] == 0xFE) &&
 348                 (s->data[11] == 0x00) &&
 349                 (s->data[12] == 0x00) &&
 350                 (s->data[13] == 0x06) &&
 351                 (s->data[14] == 0x00) &&
 352                 (s->data[15] == 0x00))
 353                 s->sega_film_skip_bytes = 6;
 354             else
 355                 s->sega_film_skip_bytes = 2;
 356         } else
 357             s->sega_film_skip_bytes = 0;
 358     }
 359
 360     s->data += 10 + s->sega_film_skip_bytes;
 361
 362     num_strips = FFMIN(num_strips, MAX_STRIPS);
 363
 364     for (i=0; i < num_strips; i++) {
 365         if ((s->data + 12) > eod)
 366             return AVERROR_INVALIDDATA;
 367
 368         s->strips[i].id = s->data[0];
 369         s->strips[i].y1 = y0;
 370         s->strips[i].x1 = 0;
 371         s->strips[i].y2 = y0 + AV_RB16 (&s->data[8]);
 372         s->strips[i].x2 = s->avctx->width;
 373
 374         strip_size = AV_RB24 (&s->data[1]) - 12;
 375         if (strip_size < 0)
 376             return AVERROR_INVALIDDATA;
 377         s->data   += 12;
 378         strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
 379
 380         if ((i > 0) && !(frame_flags & 0x01)) {
 381             memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
 382                 sizeof(s->strips[i].v4_codebook));
 383             memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
 384                 sizeof(s->strips[i].v1_codebook));
 385         }
 386
 387         result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
 388
 389         if (result != 0)
 390             return result;
 391
 392         s->data += strip_size;
 393         y0    = s->strips[i].y2;
 394     }
 395     return 0;
 396 }
 397
 398 static av_cold int cinepak_decode_init(AVCodecContext *avctx)
 399 {
 400     CinepakContext *s = avctx->priv_data;
 401
 402     s->avctx = avctx;
 403     s->width = (avctx->width + 3) & ~3;
 404     s->height = (avctx->height + 3) & ~3;
 405     s->sega_film_skip_bytes = -1;  /* uninitialized state */
 406
 407     // check for paletted data
 408     if (avctx->bits_per_coded_sample != 8) {
 409         s->palette_video = 0;
 410         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
 411     } else {
 412         s->palette_video = 1;
 413         avctx->pix_fmt = AV_PIX_FMT_PAL8;
 414     }
 415
 416     s->frame.data[0] = NULL;
 417
 418     return 0;
 419 }
 420
 421 static int cinepak_decode_frame(AVCodecContext *avctx,
 422                                 void *data, int *data_size,
 423                                 AVPacket *avpkt)
 424 {
 425     const uint8_t *buf = avpkt->data;
 426     int ret = 0, buf_size = avpkt->size;
 427     CinepakContext *s = avctx->priv_data;
 428
 429     s->data = buf;
 430     s->size = buf_size;
 431
 432     s->frame.reference = 1;
 433     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
 434                             FF_BUFFER_HINTS_REUSABLE;
 435     if ((ret = avctx->reget_buffer(avctx, &s->frame))) {
 436         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 437         return ret;
 438     }
 439
 440     if (s->palette_video) {
 441         const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
 442         if (pal) {
 443             s->frame.palette_has_changed = 1;
 444             memcpy(s->pal, pal, AVPALETTE_SIZE);
 445         }
 446     }
 447
 448     cinepak_decode(s);
 449
 450     if (s->palette_video)
 451         memcpy (s->frame.data[1], s->pal, AVPALETTE_SIZE);
 452
 453     *data_size = sizeof(AVFrame);
 454     *(AVFrame*)data = s->frame;
 455
 456     /* report that the buffer was completely consumed */
 457     return buf_size;
 458 }
 459
 460 static av_cold int cinepak_decode_end(AVCodecContext *avctx)
 461 {
 462     CinepakContext *s = avctx->priv_data;
 463
 464     if (s->frame.data[0])
 465         avctx->release_buffer(avctx, &s->frame);
 466
 467     return 0;
 468 }
 469
 470 AVCodec ff_cinepak_decoder = {
 471     .name           = "cinepak",
 472     .type           = AVMEDIA_TYPE_VIDEO,
 473     .id             = AV_CODEC_ID_CINEPAK,
 474     .priv_data_size = sizeof(CinepakContext),
 475     .init           = cinepak_decode_init,
 476     .close          = cinepak_decode_end,
 477     .decode         = cinepak_decode_frame,
 478     .capabilities   = CODEC_CAP_DR1,
 479     .long_name      = NULL_IF_CONFIG_SMALL("Cinepak"),
 480 };