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   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/intreadwrite.h"
  38 #include "avcodec.h"
  39
  40
  41 typedef struct {
  42     uint8_t  y0, y1, y2, y3;
  43     uint8_t  u, v;
  44 } cvid_codebook;
  45
  46 #define MAX_STRIPS      32
  47
  48 typedef struct {
  49     uint16_t          id;
  50     uint16_t          x1, y1;
  51     uint16_t          x2, y2;
  52     cvid_codebook     v4_codebook[256];
  53     cvid_codebook     v1_codebook[256];
  54 } cvid_strip;
  55
  56 typedef struct CinepakContext {
  57
  58     AVCodecContext *avctx;
  59     AVFrame frame;
  60
  61     const unsigned char *data;
  62     int size;
  63
  64     int width, height;
  65
  66     int palette_video;
  67     cvid_strip strips[MAX_STRIPS];
  68
  69     int sega_film_skip_bytes;
  70
  71     uint32_t pal[256];
  72 } CinepakContext;
  73
  74 static void cinepak_decode_codebook (cvid_codebook *codebook,
  75                                      int chunk_id, int size, const uint8_t *data)
  76 {
  77     const uint8_t *eod = (data + size);
  78     uint32_t flag, mask;
  79     int      i, n;
  80
  81     /* check if this chunk contains 4- or 6-element vectors */
  82     n    = (chunk_id & 0x04) ? 4 : 6;
  83     flag = 0;
  84     mask = 0;
  85
  86     for (i=0; i < 256; i++) {
  87         if ((chunk_id & 0x01) && !(mask >>= 1)) {
  88             if ((data + 4) > eod)
  89                 break;
  90
  91             flag  = AV_RB32 (data);
  92             data += 4;
  93             mask  = 0x80000000;
  94         }
  95
  96         if (!(chunk_id & 0x01) || (flag & mask)) {
  97             if ((data + n) > eod)
  98                 break;
  99
 100             if (n == 6) {
 101                 codebook[i].y0 = *data++;
 102                 codebook[i].y1 = *data++;
 103                 codebook[i].y2 = *data++;
 104                 codebook[i].y3 = *data++;
 105                 codebook[i].u  = 128 + *data++;
 106                 codebook[i].v  = 128 + *data++;
 107             } else {
 108                 /* this codebook type indicates either greyscale or
 109                  * palettized video; if palettized, U & V components will
 110                  * not be used so it is safe to set them to 128 for the
 111                  * benefit of greyscale rendering in YUV420P */
 112                 codebook[i].y0 = *data++;
 113                 codebook[i].y1 = *data++;
 114                 codebook[i].y2 = *data++;
 115                 codebook[i].y3 = *data++;
 116                 codebook[i].u  = 128;
 117                 codebook[i].v  = 128;
 118             }
 119         }
 120     }
 121 }
 122
 123 static int cinepak_decode_vectors (CinepakContext *s, cvid_strip *strip,
 124                                    int chunk_id, int size, const uint8_t *data)
 125 {
 126     const uint8_t   *eod = (data + size);
 127     uint32_t         flag, mask;
 128     cvid_codebook   *codebook;
 129     unsigned int     x, y;
 130     uint32_t         iy[4];
 131     uint32_t         iu[2];
 132     uint32_t         iv[2];
 133
 134     flag = 0;
 135     mask = 0;
 136
 137     for (y=strip->y1; y < strip->y2; y+=4) {
 138
 139         iy[0] = strip->x1 + (y * s->frame.linesize[0]);
 140         iy[1] = iy[0] + s->frame.linesize[0];
 141         iy[2] = iy[1] + s->frame.linesize[0];
 142         iy[3] = iy[2] + s->frame.linesize[0];
 143         iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]);
 144         iu[1] = iu[0] + s->frame.linesize[1];
 145         iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]);
 146         iv[1] = iv[0] + s->frame.linesize[2];
 147
 148         for (x=strip->x1; x < strip->x2; x+=4) {
 149             if ((chunk_id & 0x01) && !(mask >>= 1)) {
 150                 if ((data + 4) > eod)
 151                     return AVERROR_INVALIDDATA;
 152
 153                 flag  = AV_RB32 (data);
 154                 data += 4;
 155                 mask  = 0x80000000;
 156             }
 157
 158             if (!(chunk_id & 0x01) || (flag & mask)) {
 159                 if (!(chunk_id & 0x02) && !(mask >>= 1)) {
 160                     if ((data + 4) > eod)
 161                         return AVERROR_INVALIDDATA;
 162
 163                     flag  = AV_RB32 (data);
 164                     data += 4;
 165                     mask  = 0x80000000;
 166                 }
 167
 168                 if ((chunk_id & 0x02) || (~flag & mask)) {
 169                     if (data >= eod)
 170                         return AVERROR_INVALIDDATA;
 171
 172                     codebook = &strip->v1_codebook[*data++];
 173                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 174                     s->frame.data[0][iy[0] + 1] = codebook->y0;
 175                     s->frame.data[0][iy[1] + 0] = codebook->y0;
 176                     s->frame.data[0][iy[1] + 1] = codebook->y0;
 177                     if (!s->palette_video) {
 178                         s->frame.data[1][iu[0]] = codebook->u;
 179                         s->frame.data[2][iv[0]] = codebook->v;
 180                     }
 181
 182                     s->frame.data[0][iy[0] + 2] = codebook->y1;
 183                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 184                     s->frame.data[0][iy[1] + 2] = codebook->y1;
 185                     s->frame.data[0][iy[1] + 3] = codebook->y1;
 186                     if (!s->palette_video) {
 187                         s->frame.data[1][iu[0] + 1] = codebook->u;
 188                         s->frame.data[2][iv[0] + 1] = codebook->v;
 189                     }
 190
 191                     s->frame.data[0][iy[2] + 0] = codebook->y2;
 192                     s->frame.data[0][iy[2] + 1] = codebook->y2;
 193                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 194                     s->frame.data[0][iy[3] + 1] = codebook->y2;
 195                     if (!s->palette_video) {
 196                         s->frame.data[1][iu[1]] = codebook->u;
 197                         s->frame.data[2][iv[1]] = codebook->v;
 198                     }
 199
 200                     s->frame.data[0][iy[2] + 2] = codebook->y3;
 201                     s->frame.data[0][iy[2] + 3] = codebook->y3;
 202                     s->frame.data[0][iy[3] + 2] = codebook->y3;
 203                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 204                     if (!s->palette_video) {
 205                         s->frame.data[1][iu[1] + 1] = codebook->u;
 206                         s->frame.data[2][iv[1] + 1] = codebook->v;
 207                     }
 208
 209                 } else if (flag & mask) {
 210                     if ((data + 4) > eod)
 211                         return AVERROR_INVALIDDATA;
 212
 213                     codebook = &strip->v4_codebook[*data++];
 214                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 215                     s->frame.data[0][iy[0] + 1] = codebook->y1;
 216                     s->frame.data[0][iy[1] + 0] = codebook->y2;
 217                     s->frame.data[0][iy[1] + 1] = codebook->y3;
 218                     if (!s->palette_video) {
 219                         s->frame.data[1][iu[0]] = codebook->u;
 220                         s->frame.data[2][iv[0]] = codebook->v;
 221                     }
 222
 223                     codebook = &strip->v4_codebook[*data++];
 224                     s->frame.data[0][iy[0] + 2] = codebook->y0;
 225                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 226                     s->frame.data[0][iy[1] + 2] = codebook->y2;
 227                     s->frame.data[0][iy[1] + 3] = codebook->y3;
 228                     if (!s->palette_video) {
 229                         s->frame.data[1][iu[0] + 1] = codebook->u;
 230                         s->frame.data[2][iv[0] + 1] = codebook->v;
 231                     }
 232
 233                     codebook = &strip->v4_codebook[*data++];
 234                     s->frame.data[0][iy[2] + 0] = codebook->y0;
 235                     s->frame.data[0][iy[2] + 1] = codebook->y1;
 236                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 237                     s->frame.data[0][iy[3] + 1] = codebook->y3;
 238                     if (!s->palette_video) {
 239                         s->frame.data[1][iu[1]] = codebook->u;
 240                         s->frame.data[2][iv[1]] = codebook->v;
 241                     }
 242
 243                     codebook = &strip->v4_codebook[*data++];
 244                     s->frame.data[0][iy[2] + 2] = codebook->y0;
 245                     s->frame.data[0][iy[2] + 3] = codebook->y1;
 246                     s->frame.data[0][iy[3] + 2] = codebook->y2;
 247                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 248                     if (!s->palette_video) {
 249                         s->frame.data[1][iu[1] + 1] = codebook->u;
 250                         s->frame.data[2][iv[1] + 1] = codebook->v;
 251                     }
 252
 253                 }
 254             }
 255
 256             iy[0] += 4;  iy[1] += 4;
 257             iy[2] += 4;  iy[3] += 4;
 258             iu[0] += 2;  iu[1] += 2;
 259             iv[0] += 2;  iv[1] += 2;
 260         }
 261     }
 262
 263     return 0;
 264 }
 265
 266 static int cinepak_decode_strip (CinepakContext *s,
 267                                  cvid_strip *strip, const uint8_t *data, int size)
 268 {
 269     const uint8_t *eod = (data + size);
 270     int      chunk_id, chunk_size;
 271
 272     /* coordinate sanity checks */
 273     if (strip->x2 > s->width   ||
 274         strip->y2 > s->height  ||
 275         strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
 276         return AVERROR_INVALIDDATA;
 277
 278     while ((data + 4) <= eod) {
 279         chunk_id   = data[0];
 280         chunk_size = AV_RB24 (&data[1]) - 4;
 281         if(chunk_size < 0)
 282             return AVERROR_INVALIDDATA;
 283
 284         data      += 4;
 285         chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
 286
 287         switch (chunk_id) {
 288
 289         case 0x20:
 290         case 0x21:
 291         case 0x24:
 292         case 0x25:
 293             cinepak_decode_codebook (strip->v4_codebook, chunk_id,
 294                 chunk_size, data);
 295             break;
 296
 297         case 0x22:
 298         case 0x23:
 299         case 0x26:
 300         case 0x27:
 301             cinepak_decode_codebook (strip->v1_codebook, chunk_id,
 302                 chunk_size, data);
 303             break;
 304
 305         case 0x30:
 306         case 0x31:
 307         case 0x32:
 308             return cinepak_decode_vectors (s, strip, chunk_id,
 309                 chunk_size, data);
 310         }
 311
 312         data += chunk_size;
 313     }
 314
 315     return AVERROR_INVALIDDATA;
 316 }
 317
 318 static int cinepak_decode (CinepakContext *s)
 319 {
 320     const uint8_t  *eod = (s->data + s->size);
 321     int           i, result, strip_size, frame_flags, num_strips;
 322     int           y0 = 0;
 323     int           encoded_buf_size;
 324
 325     if (s->size < 10)
 326         return AVERROR_INVALIDDATA;
 327
 328     frame_flags = s->data[0];
 329     num_strips  = AV_RB16 (&s->data[8]);
 330     encoded_buf_size = AV_RB24(&s->data[1]);
 331
 332     /* if this is the first frame, check for deviant Sega FILM data */
 333     if (s->sega_film_skip_bytes == -1) {
 334         if (!encoded_buf_size) {
 335             av_log_ask_for_sample(s->avctx, "encoded_buf_size is 0");
 336             return AVERROR_INVALIDDATA;
 337         }
 338         if (encoded_buf_size != s->size && (s->size % encoded_buf_size) != 0) {
 339             /* If the encoded frame size differs from the frame size as indicated
 340              * by the container file, this data likely comes from a Sega FILM/CPK file.
 341              * If the frame header is followed by the bytes FE 00 00 06 00 00 then
 342              * this is probably one of the two known files that have 6 extra bytes
 343              * after the frame header. Else, assume 2 extra bytes. The container
 344              * size also cannot be a multiple of the encoded size. */
 345             if (s->size >= 16 &&
 346                 (s->data[10] == 0xFE) &&
 347                 (s->data[11] == 0x00) &&
 348                 (s->data[12] == 0x00) &&
 349                 (s->data[13] == 0x06) &&
 350                 (s->data[14] == 0x00) &&
 351                 (s->data[15] == 0x00))
 352                 s->sega_film_skip_bytes = 6;
 353             else
 354                 s->sega_film_skip_bytes = 2;
 355         } else
 356             s->sega_film_skip_bytes = 0;
 357     }
 358
 359     s->data += 10 + s->sega_film_skip_bytes;
 360
 361     num_strips = FFMIN(num_strips, MAX_STRIPS);
 362
 363     for (i=0; i < num_strips; i++) {
 364         if ((s->data + 12) > eod)
 365             return AVERROR_INVALIDDATA;
 366
 367         s->strips[i].id = s->data[0];
 368         s->strips[i].y1 = y0;
 369         s->strips[i].x1 = 0;
 370         s->strips[i].y2 = y0 + AV_RB16 (&s->data[8]);
 371         s->strips[i].x2 = s->avctx->width;
 372
 373         strip_size = AV_RB24 (&s->data[1]) - 12;
 374         if (strip_size < 0)
 375             return AVERROR_INVALIDDATA;
 376         s->data   += 12;
 377         strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
 378
 379         if ((i > 0) && !(frame_flags & 0x01)) {
 380             memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
 381                 sizeof(s->strips[i].v4_codebook));
 382             memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
 383                 sizeof(s->strips[i].v1_codebook));
 384         }
 385
 386         result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
 387
 388         if (result != 0)
 389             return result;
 390
 391         s->data += strip_size;
 392         y0    = s->strips[i].y2;
 393     }
 394     return 0;
 395 }
 396
 397 static av_cold int cinepak_decode_init(AVCodecContext *avctx)
 398 {
 399     CinepakContext *s = avctx->priv_data;
 400
 401     s->avctx = avctx;
 402     s->width = (avctx->width + 3) & ~3;
 403     s->height = (avctx->height + 3) & ~3;
 404     s->sega_film_skip_bytes = -1;  /* uninitialized state */
 405
 406     // check for paletted data
 407     if (avctx->bits_per_coded_sample != 8) {
 408         s->palette_video = 0;
 409         avctx->pix_fmt = PIX_FMT_YUV420P;
 410     } else {
 411         s->palette_video = 1;
 412         avctx->pix_fmt = PIX_FMT_PAL8;
 413     }
 414
 415     s->frame.data[0] = NULL;
 416
 417     return 0;
 418 }
 419
 420 static int cinepak_decode_frame(AVCodecContext *avctx,
 421                                 void *data, int *data_size,
 422                                 AVPacket *avpkt)
 423 {
 424     const uint8_t *buf = avpkt->data;
 425     int ret = 0, buf_size = avpkt->size;
 426     CinepakContext *s = avctx->priv_data;
 427
 428     s->data = buf;
 429     s->size = buf_size;
 430
 431     s->frame.reference = 1;
 432     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
 433                             FF_BUFFER_HINTS_REUSABLE;
 434     if ((ret = avctx->reget_buffer(avctx, &s->frame))) {
 435         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 436         return ret;
 437     }
 438
 439     if (s->palette_video) {
 440         const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
 441         if (pal) {
 442             s->frame.palette_has_changed = 1;
 443             memcpy(s->pal, pal, AVPALETTE_SIZE);
 444         }
 445     }
 446
 447     cinepak_decode(s);
 448
 449     if (s->palette_video)
 450         memcpy (s->frame.data[1], s->pal, AVPALETTE_SIZE);
 451
 452     *data_size = sizeof(AVFrame);
 453     *(AVFrame*)data = s->frame;
 454
 455     /* report that the buffer was completely consumed */
 456     return buf_size;
 457 }
 458
 459 static av_cold int cinepak_decode_end(AVCodecContext *avctx)
 460 {
 461     CinepakContext *s = avctx->priv_data;
 462
 463     if (s->frame.data[0])
 464         avctx->release_buffer(avctx, &s->frame);
 465
 466     return 0;
 467 }
 468
 469 AVCodec ff_cinepak_decoder = {
 470     .name           = "cinepak",
 471     .type           = AVMEDIA_TYPE_VIDEO,
 472     .id             = CODEC_ID_CINEPAK,
 473     .priv_data_size = sizeof(CinepakContext),
 474     .init           = cinepak_decode_init,
 475     .close          = cinepak_decode_end,
 476     .decode         = cinepak_decode_frame,
 477     .capabilities   = CODEC_CAP_DR1,
 478     .long_name      = NULL_IF_CONFIG_SMALL("Cinepak"),
 479 };