libavcodec/cinepak.c

   1 /*
   2  * Cinepak Video Decoder
   3  * Copyright (C) 2003 the ffmpeg project
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg 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  * FFmpeg 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 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 libavcodec/cinepak.c
  24  * Cinepak video decoder
  25  * by Ewald Snel <ewald@rambo.its.tudelft.nl>
  26  * For more information on the Cinepak algorithm, visit:
  27  *   http://www.csse.monash.edu.au/~timf/
  28  * For more information on the quirky data inside Sega FILM/CPK files, visit:
  29  *   http://wiki.multimedia.cx/index.php?title=Sega_FILM
  30  */
  31
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <unistd.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 } CinepakContext;
  72
  73 static void cinepak_decode_codebook (cvid_codebook *codebook,
  74                                      int chunk_id, int size, const uint8_t *data)
  75 {
  76     const uint8_t *eod = (data + size);
  77     uint32_t flag, mask;
  78     int      i, n;
  79
  80     /* check if this chunk contains 4- or 6-element vectors */
  81     n    = (chunk_id & 0x04) ? 4 : 6;
  82     flag = 0;
  83     mask = 0;
  84
  85     for (i=0; i < 256; i++) {
  86         if ((chunk_id & 0x01) && !(mask >>= 1)) {
  87             if ((data + 4) > eod)
  88                 break;
  89
  90             flag  = AV_RB32 (data);
  91             data += 4;
  92             mask  = 0x80000000;
  93         }
  94
  95         if (!(chunk_id & 0x01) || (flag & mask)) {
  96             if ((data + n) > eod)
  97                 break;
  98
  99             if (n == 6) {
 100                 codebook[i].y0 = *data++;
 101                 codebook[i].y1 = *data++;
 102                 codebook[i].y2 = *data++;
 103                 codebook[i].y3 = *data++;
 104                 codebook[i].u  = 128 + *data++;
 105                 codebook[i].v  = 128 + *data++;
 106             } else {
 107                 /* this codebook type indicates either greyscale or
 108                  * palettized video; if palettized, U & V components will
 109                  * not be used so it is safe to set them to 128 for the
 110                  * benefit of greyscale rendering in YUV420P */
 111                 codebook[i].y0 = *data++;
 112                 codebook[i].y1 = *data++;
 113                 codebook[i].y2 = *data++;
 114                 codebook[i].y3 = *data++;
 115                 codebook[i].u  = 128;
 116                 codebook[i].v  = 128;
 117             }
 118         }
 119     }
 120 }
 121
 122 static int cinepak_decode_vectors (CinepakContext *s, cvid_strip *strip,
 123                                    int chunk_id, int size, const uint8_t *data)
 124 {
 125     const uint8_t   *eod = (data + size);
 126     uint32_t         flag, mask;
 127     cvid_codebook   *codebook;
 128     unsigned int     x, y;
 129     uint32_t         iy[4];
 130     uint32_t         iu[2];
 131     uint32_t         iv[2];
 132
 133     flag = 0;
 134     mask = 0;
 135
 136     for (y=strip->y1; y < strip->y2; y+=4) {
 137
 138         iy[0] = strip->x1 + (y * s->frame.linesize[0]);
 139         iy[1] = iy[0] + s->frame.linesize[0];
 140         iy[2] = iy[1] + s->frame.linesize[0];
 141         iy[3] = iy[2] + s->frame.linesize[0];
 142         iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]);
 143         iu[1] = iu[0] + s->frame.linesize[1];
 144         iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]);
 145         iv[1] = iv[0] + s->frame.linesize[2];
 146
 147         for (x=strip->x1; x < strip->x2; x+=4) {
 148             if ((chunk_id & 0x01) && !(mask >>= 1)) {
 149                 if ((data + 4) > eod)
 150                     return -1;
 151
 152                 flag  = AV_RB32 (data);
 153                 data += 4;
 154                 mask  = 0x80000000;
 155             }
 156
 157             if (!(chunk_id & 0x01) || (flag & mask)) {
 158                 if (!(chunk_id & 0x02) && !(mask >>= 1)) {
 159                     if ((data + 4) > eod)
 160                         return -1;
 161
 162                     flag  = AV_RB32 (data);
 163                     data += 4;
 164                     mask  = 0x80000000;
 165                 }
 166
 167                 if ((chunk_id & 0x02) || (~flag & mask)) {
 168                     if (data >= eod)
 169                         return -1;
 170
 171                     codebook = &strip->v1_codebook[*data++];
 172                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 173                     s->frame.data[0][iy[0] + 1] = codebook->y0;
 174                     s->frame.data[0][iy[1] + 0] = codebook->y0;
 175                     s->frame.data[0][iy[1] + 1] = codebook->y0;
 176                     if (!s->palette_video) {
 177                         s->frame.data[1][iu[0]] = codebook->u;
 178                         s->frame.data[2][iv[0]] = codebook->v;
 179                     }
 180
 181                     s->frame.data[0][iy[0] + 2] = codebook->y1;
 182                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 183                     s->frame.data[0][iy[1] + 2] = codebook->y1;
 184                     s->frame.data[0][iy[1] + 3] = codebook->y1;
 185                     if (!s->palette_video) {
 186                         s->frame.data[1][iu[0] + 1] = codebook->u;
 187                         s->frame.data[2][iv[0] + 1] = codebook->v;
 188                     }
 189
 190                     s->frame.data[0][iy[2] + 0] = codebook->y2;
 191                     s->frame.data[0][iy[2] + 1] = codebook->y2;
 192                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 193                     s->frame.data[0][iy[3] + 1] = codebook->y2;
 194                     if (!s->palette_video) {
 195                         s->frame.data[1][iu[1]] = codebook->u;
 196                         s->frame.data[2][iv[1]] = codebook->v;
 197                     }
 198
 199                     s->frame.data[0][iy[2] + 2] = codebook->y3;
 200                     s->frame.data[0][iy[2] + 3] = codebook->y3;
 201                     s->frame.data[0][iy[3] + 2] = codebook->y3;
 202                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 203                     if (!s->palette_video) {
 204                         s->frame.data[1][iu[1] + 1] = codebook->u;
 205                         s->frame.data[2][iv[1] + 1] = codebook->v;
 206                     }
 207
 208                 } else if (flag & mask) {
 209                     if ((data + 4) > eod)
 210                         return -1;
 211
 212                     codebook = &strip->v4_codebook[*data++];
 213                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 214                     s->frame.data[0][iy[0] + 1] = codebook->y1;
 215                     s->frame.data[0][iy[1] + 0] = codebook->y2;
 216                     s->frame.data[0][iy[1] + 1] = codebook->y3;
 217                     if (!s->palette_video) {
 218                         s->frame.data[1][iu[0]] = codebook->u;
 219                         s->frame.data[2][iv[0]] = codebook->v;
 220                     }
 221
 222                     codebook = &strip->v4_codebook[*data++];
 223                     s->frame.data[0][iy[0] + 2] = codebook->y0;
 224                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 225                     s->frame.data[0][iy[1] + 2] = codebook->y2;
 226                     s->frame.data[0][iy[1] + 3] = codebook->y3;
 227                     if (!s->palette_video) {
 228                         s->frame.data[1][iu[0] + 1] = codebook->u;
 229                         s->frame.data[2][iv[0] + 1] = codebook->v;
 230                     }
 231
 232                     codebook = &strip->v4_codebook[*data++];
 233                     s->frame.data[0][iy[2] + 0] = codebook->y0;
 234                     s->frame.data[0][iy[2] + 1] = codebook->y1;
 235                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 236                     s->frame.data[0][iy[3] + 1] = codebook->y3;
 237                     if (!s->palette_video) {
 238                         s->frame.data[1][iu[1]] = codebook->u;
 239                         s->frame.data[2][iv[1]] = codebook->v;
 240                     }
 241
 242                     codebook = &strip->v4_codebook[*data++];
 243                     s->frame.data[0][iy[2] + 2] = codebook->y0;
 244                     s->frame.data[0][iy[2] + 3] = codebook->y1;
 245                     s->frame.data[0][iy[3] + 2] = codebook->y2;
 246                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 247                     if (!s->palette_video) {
 248                         s->frame.data[1][iu[1] + 1] = codebook->u;
 249                         s->frame.data[2][iv[1] + 1] = codebook->v;
 250                     }
 251
 252                 }
 253             }
 254
 255             iy[0] += 4;  iy[1] += 4;
 256             iy[2] += 4;  iy[3] += 4;
 257             iu[0] += 2;  iu[1] += 2;
 258             iv[0] += 2;  iv[1] += 2;
 259         }
 260     }
 261
 262     return 0;
 263 }
 264
 265 static int cinepak_decode_strip (CinepakContext *s,
 266                                  cvid_strip *strip, const uint8_t *data, int size)
 267 {
 268     const uint8_t *eod = (data + size);
 269     int      chunk_id, chunk_size;
 270
 271     /* coordinate sanity checks */
 272     if (strip->x1 >= s->width  || strip->x2 > s->width  ||
 273         strip->y1 >= s->height || strip->y2 > s->height ||
 274         strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
 275         return -1;
 276
 277     while ((data + 4) <= eod) {
 278         chunk_id   = data[0];
 279         chunk_size = AV_RB24 (&data[1]) - 4;
 280         if(chunk_size < 0)
 281             return -1;
 282
 283         data      += 4;
 284         chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
 285
 286         switch (chunk_id) {
 287
 288         case 0x20:
 289         case 0x21:
 290         case 0x24:
 291         case 0x25:
 292             cinepak_decode_codebook (strip->v4_codebook, chunk_id,
 293                 chunk_size, data);
 294             break;
 295
 296         case 0x22:
 297         case 0x23:
 298         case 0x26:
 299         case 0x27:
 300             cinepak_decode_codebook (strip->v1_codebook, chunk_id,
 301                 chunk_size, data);
 302             break;
 303
 304         case 0x30:
 305         case 0x31:
 306         case 0x32:
 307             return cinepak_decode_vectors (s, strip, chunk_id,
 308                 chunk_size, data);
 309         }
 310
 311         data += chunk_size;
 312     }
 313
 314     return -1;
 315 }
 316
 317 static int cinepak_decode (CinepakContext *s)
 318 {
 319     const uint8_t  *eod = (s->data + s->size);
 320     int           i, result, strip_size, frame_flags, num_strips;
 321     int           y0 = 0;
 322     int           encoded_buf_size;
 323
 324     if (s->size < 10)
 325         return -1;
 326
 327     frame_flags = s->data[0];
 328     num_strips  = AV_RB16 (&s->data[8]);
 329     encoded_buf_size = ((s->data[1] << 16) | AV_RB16 (&s->data[2]));
 330
 331     /* if this is the first frame, check for deviant Sega FILM data */
 332     if (s->sega_film_skip_bytes == -1) {
 333         if (encoded_buf_size != s->size) {
 334             /* If the encoded frame size differs from the frame size as indicated
 335              * by the container file, this data likely comes from a Sega FILM/CPK file.
 336              * If the frame header is followed by the bytes FE 00 00 06 00 00 then
 337              * this is probably one of the two known files that have 6 extra bytes
 338              * after the frame header. Else, assume 2 extra bytes. */
 339             if ((s->data[10] == 0xFE) &&
 340                 (s->data[11] == 0x00) &&
 341                 (s->data[12] == 0x00) &&
 342                 (s->data[13] == 0x06) &&
 343                 (s->data[14] == 0x00) &&
 344                 (s->data[15] == 0x00))
 345                 s->sega_film_skip_bytes = 6;
 346             else
 347                 s->sega_film_skip_bytes = 2;
 348         } else
 349             s->sega_film_skip_bytes = 0;
 350     }
 351
 352     s->data += 10 + s->sega_film_skip_bytes;
 353
 354     if (num_strips > MAX_STRIPS)
 355         num_strips = MAX_STRIPS;
 356
 357     for (i=0; i < num_strips; i++) {
 358         if ((s->data + 12) > eod)
 359             return -1;
 360
 361         s->strips[i].id = s->data[0];
 362         s->strips[i].y1 = y0;
 363         s->strips[i].x1 = 0;
 364         s->strips[i].y2 = y0 + AV_RB16 (&s->data[8]);
 365         s->strips[i].x2 = s->avctx->width;
 366
 367         strip_size = AV_RB24 (&s->data[1]) - 12;
 368         s->data   += 12;
 369         strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
 370
 371         if ((i > 0) && !(frame_flags & 0x01)) {
 372             memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
 373                 sizeof(s->strips[i].v4_codebook));
 374             memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
 375                 sizeof(s->strips[i].v1_codebook));
 376         }
 377
 378         result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
 379
 380         if (result != 0)
 381             return result;
 382
 383         s->data += strip_size;
 384         y0    = s->strips[i].y2;
 385     }
 386     return 0;
 387 }
 388
 389 static av_cold int cinepak_decode_init(AVCodecContext *avctx)
 390 {
 391     CinepakContext *s = avctx->priv_data;
 392
 393     s->avctx = avctx;
 394     s->width = (avctx->width + 3) & ~3;
 395     s->height = (avctx->height + 3) & ~3;
 396     s->sega_film_skip_bytes = -1;  /* uninitialized state */
 397
 398     // check for paletted data
 399     if ((avctx->palctrl == NULL) || (avctx->bits_per_coded_sample == 40)) {
 400         s->palette_video = 0;
 401         avctx->pix_fmt = PIX_FMT_YUV420P;
 402     } else {
 403         s->palette_video = 1;
 404         avctx->pix_fmt = PIX_FMT_PAL8;
 405     }
 406
 407     s->frame.data[0] = NULL;
 408
 409     return 0;
 410 }
 411
 412 static int cinepak_decode_frame(AVCodecContext *avctx,
 413                                 void *data, int *data_size,
 414                                 AVPacket *avpkt)
 415 {
 416     const uint8_t *buf = avpkt->data;
 417     int buf_size = avpkt->size;
 418     CinepakContext *s = avctx->priv_data;
 419
 420     s->data = buf;
 421     s->size = buf_size;
 422
 423     s->frame.reference = 1;
 424     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
 425                             FF_BUFFER_HINTS_REUSABLE;
 426     if (avctx->reget_buffer(avctx, &s->frame)) {
 427         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 428         return -1;
 429     }
 430
 431     cinepak_decode(s);
 432
 433     if (s->palette_video) {
 434         memcpy (s->frame.data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
 435         if (avctx->palctrl->palette_changed) {
 436             s->frame.palette_has_changed = 1;
 437             avctx->palctrl->palette_changed = 0;
 438         } else
 439             s->frame.palette_has_changed = 0;
 440     }
 441
 442     *data_size = sizeof(AVFrame);
 443     *(AVFrame*)data = s->frame;
 444
 445     /* report that the buffer was completely consumed */
 446     return buf_size;
 447 }
 448
 449 static av_cold int cinepak_decode_end(AVCodecContext *avctx)
 450 {
 451     CinepakContext *s = avctx->priv_data;
 452
 453     if (s->frame.data[0])
 454         avctx->release_buffer(avctx, &s->frame);
 455
 456     return 0;
 457 }
 458
 459 AVCodec cinepak_decoder = {
 460     "cinepak",
 461     CODEC_TYPE_VIDEO,
 462     CODEC_ID_CINEPAK,
 463     sizeof(CinepakContext),
 464     cinepak_decode_init,
 465     NULL,
 466     cinepak_decode_end,
 467     cinepak_decode_frame,
 468     CODEC_CAP_DR1,
 469     .long_name = NULL_IF_CONFIG_SMALL("Cinepak"),
 470 };