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 #include "internal.h"
  41
  42
  43 typedef struct cvid_codebook {
  44     uint8_t  y0, y1, y2, y3;
  45     uint8_t  u, v;
  46 } cvid_codebook;
  47
  48 #define MAX_STRIPS      32
  49
  50 typedef struct cvid_strip {
  51     uint16_t          id;
  52     uint16_t          x1, y1;
  53     uint16_t          x2, y2;
  54     cvid_codebook     v4_codebook[256];
  55     cvid_codebook     v1_codebook[256];
  56 } cvid_strip;
  57
  58 typedef struct CinepakContext {
  59
  60     AVCodecContext *avctx;
  61     AVFrame *frame;
  62
  63     const unsigned char *data;
  64     int size;
  65
  66     int width, height;
  67
  68     int palette_video;
  69     cvid_strip strips[MAX_STRIPS];
  70
  71     int sega_film_skip_bytes;
  72
  73     uint32_t pal[256];
  74 } CinepakContext;
  75
  76 static void cinepak_decode_codebook (cvid_codebook *codebook,
  77                                      int chunk_id, int size, const uint8_t *data)
  78 {
  79     const uint8_t *eod = (data + size);
  80     uint32_t flag, mask;
  81     int      i, n;
  82
  83     /* check if this chunk contains 4- or 6-element vectors */
  84     n    = (chunk_id & 0x04) ? 4 : 6;
  85     flag = 0;
  86     mask = 0;
  87
  88     for (i=0; i < 256; i++) {
  89         if ((chunk_id & 0x01) && !(mask >>= 1)) {
  90             if ((data + 4) > eod)
  91                 break;
  92
  93             flag  = AV_RB32 (data);
  94             data += 4;
  95             mask  = 0x80000000;
  96         }
  97
  98         if (!(chunk_id & 0x01) || (flag & mask)) {
  99             if ((data + n) > eod)
 100                 break;
 101
 102             if (n == 6) {
 103                 codebook[i].y0 = *data++;
 104                 codebook[i].y1 = *data++;
 105                 codebook[i].y2 = *data++;
 106                 codebook[i].y3 = *data++;
 107                 codebook[i].u  = 128 + *data++;
 108                 codebook[i].v  = 128 + *data++;
 109             } else {
 110                 /* this codebook type indicates either greyscale or
 111                  * palettized video; if palettized, U & V components will
 112                  * not be used so it is safe to set them to 128 for the
 113                  * benefit of greyscale rendering in YUV420P */
 114                 codebook[i].y0 = *data++;
 115                 codebook[i].y1 = *data++;
 116                 codebook[i].y2 = *data++;
 117                 codebook[i].y3 = *data++;
 118                 codebook[i].u  = 128;
 119                 codebook[i].v  = 128;
 120             }
 121         }
 122     }
 123 }
 124
 125 static int cinepak_decode_vectors (CinepakContext *s, cvid_strip *strip,
 126                                    int chunk_id, int size, const uint8_t *data)
 127 {
 128     const uint8_t   *eod = (data + size);
 129     uint32_t         flag, mask;
 130     cvid_codebook   *codebook;
 131     unsigned int     x, y;
 132     uint32_t         iy[4];
 133     uint32_t         iu[2];
 134     uint32_t         iv[2];
 135
 136     flag = 0;
 137     mask = 0;
 138
 139     for (y=strip->y1; y < strip->y2; y+=4) {
 140
 141         iy[0] = strip->x1 + (y * s->frame->linesize[0]);
 142         iy[1] = iy[0] + s->frame->linesize[0];
 143         iy[2] = iy[1] + s->frame->linesize[0];
 144         iy[3] = iy[2] + s->frame->linesize[0];
 145         iu[0] = (strip->x1/2) + ((y/2) * s->frame->linesize[1]);
 146         iu[1] = iu[0] + s->frame->linesize[1];
 147         iv[0] = (strip->x1/2) + ((y/2) * s->frame->linesize[2]);
 148         iv[1] = iv[0] + s->frame->linesize[2];
 149
 150         for (x=strip->x1; x < strip->x2; x+=4) {
 151             if ((chunk_id & 0x01) && !(mask >>= 1)) {
 152                 if ((data + 4) > eod)
 153                     return AVERROR_INVALIDDATA;
 154
 155                 flag  = AV_RB32 (data);
 156                 data += 4;
 157                 mask  = 0x80000000;
 158             }
 159
 160             if (!(chunk_id & 0x01) || (flag & mask)) {
 161                 if (!(chunk_id & 0x02) && !(mask >>= 1)) {
 162                     if ((data + 4) > eod)
 163                         return AVERROR_INVALIDDATA;
 164
 165                     flag  = AV_RB32 (data);
 166                     data += 4;
 167                     mask  = 0x80000000;
 168                 }
 169
 170                 if ((chunk_id & 0x02) || (~flag & mask)) {
 171                     if (data >= eod)
 172                         return AVERROR_INVALIDDATA;
 173
 174                     codebook = &strip->v1_codebook[*data++];
 175                     s->frame->data[0][iy[0] + 0] = codebook->y0;
 176                     s->frame->data[0][iy[0] + 1] = codebook->y0;
 177                     s->frame->data[0][iy[1] + 0] = codebook->y0;
 178                     s->frame->data[0][iy[1] + 1] = codebook->y0;
 179                     if (!s->palette_video) {
 180                         s->frame->data[1][iu[0]] = codebook->u;
 181                         s->frame->data[2][iv[0]] = codebook->v;
 182                     }
 183
 184                     s->frame->data[0][iy[0] + 2] = codebook->y1;
 185                     s->frame->data[0][iy[0] + 3] = codebook->y1;
 186                     s->frame->data[0][iy[1] + 2] = codebook->y1;
 187                     s->frame->data[0][iy[1] + 3] = codebook->y1;
 188                     if (!s->palette_video) {
 189                         s->frame->data[1][iu[0] + 1] = codebook->u;
 190                         s->frame->data[2][iv[0] + 1] = codebook->v;
 191                     }
 192
 193                     s->frame->data[0][iy[2] + 0] = codebook->y2;
 194                     s->frame->data[0][iy[2] + 1] = codebook->y2;
 195                     s->frame->data[0][iy[3] + 0] = codebook->y2;
 196                     s->frame->data[0][iy[3] + 1] = codebook->y2;
 197                     if (!s->palette_video) {
 198                         s->frame->data[1][iu[1]] = codebook->u;
 199                         s->frame->data[2][iv[1]] = codebook->v;
 200                     }
 201
 202                     s->frame->data[0][iy[2] + 2] = codebook->y3;
 203                     s->frame->data[0][iy[2] + 3] = codebook->y3;
 204                     s->frame->data[0][iy[3] + 2] = codebook->y3;
 205                     s->frame->data[0][iy[3] + 3] = codebook->y3;
 206                     if (!s->palette_video) {
 207                         s->frame->data[1][iu[1] + 1] = codebook->u;
 208                         s->frame->data[2][iv[1] + 1] = codebook->v;
 209                     }
 210
 211                 } else if (flag & mask) {
 212                     if ((data + 4) > eod)
 213                         return AVERROR_INVALIDDATA;
 214
 215                     codebook = &strip->v4_codebook[*data++];
 216                     s->frame->data[0][iy[0] + 0] = codebook->y0;
 217                     s->frame->data[0][iy[0] + 1] = codebook->y1;
 218                     s->frame->data[0][iy[1] + 0] = codebook->y2;
 219                     s->frame->data[0][iy[1] + 1] = codebook->y3;
 220                     if (!s->palette_video) {
 221                         s->frame->data[1][iu[0]] = codebook->u;
 222                         s->frame->data[2][iv[0]] = codebook->v;
 223                     }
 224
 225                     codebook = &strip->v4_codebook[*data++];
 226                     s->frame->data[0][iy[0] + 2] = codebook->y0;
 227                     s->frame->data[0][iy[0] + 3] = codebook->y1;
 228                     s->frame->data[0][iy[1] + 2] = codebook->y2;
 229                     s->frame->data[0][iy[1] + 3] = codebook->y3;
 230                     if (!s->palette_video) {
 231                         s->frame->data[1][iu[0] + 1] = codebook->u;
 232                         s->frame->data[2][iv[0] + 1] = codebook->v;
 233                     }
 234
 235                     codebook = &strip->v4_codebook[*data++];
 236                     s->frame->data[0][iy[2] + 0] = codebook->y0;
 237                     s->frame->data[0][iy[2] + 1] = codebook->y1;
 238                     s->frame->data[0][iy[3] + 0] = codebook->y2;
 239                     s->frame->data[0][iy[3] + 1] = codebook->y3;
 240                     if (!s->palette_video) {
 241                         s->frame->data[1][iu[1]] = codebook->u;
 242                         s->frame->data[2][iv[1]] = codebook->v;
 243                     }
 244
 245                     codebook = &strip->v4_codebook[*data++];
 246                     s->frame->data[0][iy[2] + 2] = codebook->y0;
 247                     s->frame->data[0][iy[2] + 3] = codebook->y1;
 248                     s->frame->data[0][iy[3] + 2] = codebook->y2;
 249                     s->frame->data[0][iy[3] + 3] = codebook->y3;
 250                     if (!s->palette_video) {
 251                         s->frame->data[1][iu[1] + 1] = codebook->u;
 252                         s->frame->data[2][iv[1] + 1] = codebook->v;
 253                     }
 254
 255                 }
 256             }
 257
 258             iy[0] += 4;  iy[1] += 4;
 259             iy[2] += 4;  iy[3] += 4;
 260             iu[0] += 2;  iu[1] += 2;
 261             iv[0] += 2;  iv[1] += 2;
 262         }
 263     }
 264
 265     return 0;
 266 }
 267
 268 static int cinepak_decode_strip (CinepakContext *s,
 269                                  cvid_strip *strip, const uint8_t *data, int size)
 270 {
 271     const uint8_t *eod = (data + size);
 272     int      chunk_id, chunk_size;
 273
 274     /* coordinate sanity checks */
 275     if (strip->x2 > s->width   ||
 276         strip->y2 > s->height  ||
 277         strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
 278         return AVERROR_INVALIDDATA;
 279
 280     while ((data + 4) <= eod) {
 281         chunk_id   = data[0];
 282         chunk_size = AV_RB24 (&data[1]) - 4;
 283         if(chunk_size < 0)
 284             return AVERROR_INVALIDDATA;
 285
 286         data      += 4;
 287         chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
 288
 289         switch (chunk_id) {
 290
 291         case 0x20:
 292         case 0x21:
 293         case 0x24:
 294         case 0x25:
 295             cinepak_decode_codebook (strip->v4_codebook, chunk_id,
 296                 chunk_size, data);
 297             break;
 298
 299         case 0x22:
 300         case 0x23:
 301         case 0x26:
 302         case 0x27:
 303             cinepak_decode_codebook (strip->v1_codebook, chunk_id,
 304                 chunk_size, data);
 305             break;
 306
 307         case 0x30:
 308         case 0x31:
 309         case 0x32:
 310             return cinepak_decode_vectors (s, strip, chunk_id,
 311                 chunk_size, data);
 312         }
 313
 314         data += chunk_size;
 315     }
 316
 317     return AVERROR_INVALIDDATA;
 318 }
 319
 320 static int cinepak_decode (CinepakContext *s)
 321 {
 322     const uint8_t  *eod = (s->data + s->size);
 323     int           i, result, strip_size, frame_flags, num_strips;
 324     int           y0 = 0;
 325     int           encoded_buf_size;
 326
 327     if (s->size < 10)
 328         return AVERROR_INVALIDDATA;
 329
 330     frame_flags = s->data[0];
 331     num_strips  = AV_RB16 (&s->data[8]);
 332     encoded_buf_size = AV_RB24(&s->data[1]);
 333
 334     /* if this is the first frame, check for deviant Sega FILM data */
 335     if (s->sega_film_skip_bytes == -1) {
 336         if (!encoded_buf_size) {
 337             avpriv_request_sample(s->avctx, "encoded_buf_size 0");
 338             return AVERROR_PATCHWELCOME;
 339         }
 340         if (encoded_buf_size != s->size && (s->size % encoded_buf_size) != 0) {
 341             /* If the encoded frame size differs from the frame size as indicated
 342              * by the container file, this data likely comes from a Sega FILM/CPK file.
 343              * If the frame header is followed by the bytes FE 00 00 06 00 00 then
 344              * this is probably one of the two known files that have 6 extra bytes
 345              * after the frame header. Else, assume 2 extra bytes. The container
 346              * size also cannot be a multiple of the encoded size. */
 347             if (s->size >= 16 &&
 348                 (s->data[10] == 0xFE) &&
 349                 (s->data[11] == 0x00) &&
 350                 (s->data[12] == 0x00) &&
 351                 (s->data[13] == 0x06) &&
 352                 (s->data[14] == 0x00) &&
 353                 (s->data[15] == 0x00))
 354                 s->sega_film_skip_bytes = 6;
 355             else
 356                 s->sega_film_skip_bytes = 2;
 357         } else
 358             s->sega_film_skip_bytes = 0;
 359     }
 360
 361     s->data += 10 + s->sega_film_skip_bytes;
 362
 363     num_strips = FFMIN(num_strips, MAX_STRIPS);
 364
 365     for (i=0; i < num_strips; i++) {
 366         if ((s->data + 12) > eod)
 367             return AVERROR_INVALIDDATA;
 368
 369         s->strips[i].id = s->data[0];
 370         s->strips[i].y1 = y0;
 371         s->strips[i].x1 = 0;
 372         s->strips[i].y2 = y0 + AV_RB16 (&s->data[8]);
 373         s->strips[i].x2 = s->avctx->width;
 374
 375         strip_size = AV_RB24 (&s->data[1]) - 12;
 376         if (strip_size < 0)
 377             return AVERROR_INVALIDDATA;
 378         s->data   += 12;
 379         strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
 380
 381         if ((i > 0) && !(frame_flags & 0x01)) {
 382             memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
 383                 sizeof(s->strips[i].v4_codebook));
 384             memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
 385                 sizeof(s->strips[i].v1_codebook));
 386         }
 387
 388         result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
 389
 390         if (result != 0)
 391             return result;
 392
 393         s->data += strip_size;
 394         y0    = s->strips[i].y2;
 395     }
 396     return 0;
 397 }
 398
 399 static av_cold int cinepak_decode_init(AVCodecContext *avctx)
 400 {
 401     CinepakContext *s = avctx->priv_data;
 402
 403     s->avctx = avctx;
 404     s->width = (avctx->width + 3) & ~3;
 405     s->height = (avctx->height + 3) & ~3;
 406     s->sega_film_skip_bytes = -1;  /* uninitialized state */
 407
 408     // check for paletted data
 409     if (avctx->bits_per_coded_sample != 8) {
 410         s->palette_video = 0;
 411         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
 412     } else {
 413         s->palette_video = 1;
 414         avctx->pix_fmt = AV_PIX_FMT_PAL8;
 415     }
 416
 417     s->frame = av_frame_alloc();
 418     if (!s->frame)
 419         return AVERROR(ENOMEM);
 420
 421     return 0;
 422 }
 423
 424 static int cinepak_decode_frame(AVCodecContext *avctx,
 425                                 void *data, int *got_frame,
 426                                 AVPacket *avpkt)
 427 {
 428     const uint8_t *buf = avpkt->data;
 429     int ret = 0, buf_size = avpkt->size;
 430     CinepakContext *s = avctx->priv_data;
 431
 432     s->data = buf;
 433     s->size = buf_size;
 434
 435     if ((ret = ff_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     if ((ret = av_frame_ref(data, s->frame)) < 0)
 454         return ret;
 455
 456     *got_frame = 1;
 457
 458     /* report that the buffer was completely consumed */
 459     return buf_size;
 460 }
 461
 462 static av_cold int cinepak_decode_end(AVCodecContext *avctx)
 463 {
 464     CinepakContext *s = avctx->priv_data;
 465
 466     av_frame_free(&s->frame);
 467
 468     return 0;
 469 }
 470
 471 AVCodec ff_cinepak_decoder = {
 472     .name           = "cinepak",
 473     .long_name      = NULL_IF_CONFIG_SMALL("Cinepak"),
 474     .type           = AVMEDIA_TYPE_VIDEO,
 475     .id             = AV_CODEC_ID_CINEPAK,
 476     .priv_data_size = sizeof(CinepakContext),
 477     .init           = cinepak_decode_init,
 478     .close          = cinepak_decode_end,
 479     .decode         = cinepak_decode_frame,
 480     .capabilities   = AV_CODEC_CAP_DR1,
 481 };