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   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 /**
  24  * @file cinepak.c
  25  * Cinepak video decoder
  26  * by Ewald Snel <ewald@rambo.its.tudelft.nl>
  27  * For more information on the Cinepak algorithm, visit:
  28  *   http://www.csse.monash.edu.au/~timf/
  29  */
  30
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <unistd.h>
  35
  36 #include "common.h"
  37 #include "avcodec.h"
  38 #include "dsputil.h"
  39
  40
  41 typedef struct {
  42     uint8_t  y0, y1, y2, y3;
  43     uint8_t  u, v;
  44 } cvid_codebook_t;
  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_t   v4_codebook[256];
  53     cvid_codebook_t   v1_codebook[256];
  54 } cvid_strip_t;
  55
  56 typedef struct CinepakContext {
  57
  58     AVCodecContext *avctx;
  59     DSPContext dsp;
  60     AVFrame frame;
  61
  62     unsigned char *data;
  63     int size;
  64
  65     int width, height;
  66
  67     int palette_video;
  68     cvid_strip_t strips[MAX_STRIPS];
  69
  70 } CinepakContext;
  71
  72 static void cinepak_decode_codebook (cvid_codebook_t *codebook,
  73                                      int chunk_id, int size, uint8_t *data)
  74 {
  75     uint8_t *eod = (data + size);
  76     uint32_t flag, mask;
  77     int      i, n;
  78
  79     /* check if this chunk contains 4- or 6-element vectors */
  80     n    = (chunk_id & 0x0400) ? 4 : 6;
  81     flag = 0;
  82     mask = 0;
  83
  84     for (i=0; i < 256; i++) {
  85         if ((chunk_id & 0x0100) && !(mask >>= 1)) {
  86             if ((data + 4) > eod)
  87                 break;
  88
  89             flag  = BE_32 (data);
  90             data += 4;
  91             mask  = 0x80000000;
  92         }
  93
  94         if (!(chunk_id & 0x0100) || (flag & mask)) {
  95             if ((data + n) > eod)
  96                 break;
  97
  98             if (n == 6) {
  99                 codebook[i].y0 = *data++;
 100                 codebook[i].y1 = *data++;
 101                 codebook[i].y2 = *data++;
 102                 codebook[i].y3 = *data++;
 103                 codebook[i].u  = 128 + *data++;
 104                 codebook[i].v  = 128 + *data++;
 105             } else {
 106                 /* this codebook type indicates either greyscale or
 107                  * palettized video; if palettized, U & V components will
 108                  * not be used so it is safe to set them to 128 for the
 109                  * benefit of greyscale rendering in YUV420P */
 110                 codebook[i].y0 = *data++;
 111                 codebook[i].y1 = *data++;
 112                 codebook[i].y2 = *data++;
 113                 codebook[i].y3 = *data++;
 114                 codebook[i].u  = 128;
 115                 codebook[i].v  = 128;
 116             }
 117         }
 118     }
 119 }
 120
 121 static int cinepak_decode_vectors (CinepakContext *s, cvid_strip_t *strip,
 122                                    int chunk_id, int size, uint8_t *data)
 123 {
 124     uint8_t         *eod = (data + size);
 125     uint32_t         flag, mask;
 126     cvid_codebook_t *codebook;
 127     unsigned int     x, y;
 128     uint32_t         iy[4];
 129     uint32_t         iu[2];
 130     uint32_t         iv[2];
 131
 132     flag = 0;
 133     mask = 0;
 134
 135     for (y=strip->y1; y < strip->y2; y+=4) {
 136
 137         iy[0] = strip->x1 + (y * s->frame.linesize[0]);
 138         iy[1] = iy[0] + s->frame.linesize[0];
 139         iy[2] = iy[1] + s->frame.linesize[0];
 140         iy[3] = iy[2] + s->frame.linesize[0];
 141         iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]);
 142         iu[1] = iu[0] + s->frame.linesize[1];
 143         iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]);
 144         iv[1] = iv[0] + s->frame.linesize[2];
 145
 146         for (x=strip->x1; x < strip->x2; x+=4) {
 147             if ((chunk_id & 0x0100) && !(mask >>= 1)) {
 148                 if ((data + 4) > eod)
 149                     return -1;
 150
 151                 flag  = BE_32 (data);
 152                 data += 4;
 153                 mask  = 0x80000000;
 154             }
 155
 156             if (!(chunk_id & 0x0100) || (flag & mask)) {
 157                 if (!(chunk_id & 0x0200) && !(mask >>= 1)) {
 158                     if ((data + 4) > eod)
 159                         return -1;
 160
 161                     flag  = BE_32 (data);
 162                     data += 4;
 163                     mask  = 0x80000000;
 164                 }
 165
 166                 if ((chunk_id & 0x0200) || (~flag & mask)) {
 167                     if (data >= eod)
 168                         return -1;
 169
 170                     codebook = &strip->v1_codebook[*data++];
 171                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 172                     s->frame.data[0][iy[0] + 1] = codebook->y0;
 173                     s->frame.data[0][iy[1] + 0] = codebook->y0;
 174                     s->frame.data[0][iy[1] + 1] = codebook->y0;
 175                     if (!s->palette_video) {
 176                         s->frame.data[1][iu[0]] = codebook->u;
 177                         s->frame.data[2][iv[0]] = codebook->v;
 178                     }
 179
 180                     s->frame.data[0][iy[0] + 2] = codebook->y1;
 181                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 182                     s->frame.data[0][iy[1] + 2] = codebook->y1;
 183                     s->frame.data[0][iy[1] + 3] = codebook->y1;
 184                     if (!s->palette_video) {
 185                         s->frame.data[1][iu[0] + 1] = codebook->u;
 186                         s->frame.data[2][iv[0] + 1] = codebook->v;
 187                     }
 188
 189                     s->frame.data[0][iy[2] + 0] = codebook->y2;
 190                     s->frame.data[0][iy[2] + 1] = codebook->y2;
 191                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 192                     s->frame.data[0][iy[3] + 1] = codebook->y2;
 193                     if (!s->palette_video) {
 194                         s->frame.data[1][iu[1]] = codebook->u;
 195                         s->frame.data[2][iv[1]] = codebook->v;
 196                     }
 197
 198                     s->frame.data[0][iy[2] + 2] = codebook->y3;
 199                     s->frame.data[0][iy[2] + 3] = codebook->y3;
 200                     s->frame.data[0][iy[3] + 2] = codebook->y3;
 201                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 202                     if (!s->palette_video) {
 203                         s->frame.data[1][iu[1] + 1] = codebook->u;
 204                         s->frame.data[2][iv[1] + 1] = codebook->v;
 205                     }
 206
 207                 } else if (flag & mask) {
 208                     if ((data + 4) > eod)
 209                         return -1;
 210
 211                     codebook = &strip->v4_codebook[*data++];
 212                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 213                     s->frame.data[0][iy[0] + 1] = codebook->y1;
 214                     s->frame.data[0][iy[1] + 0] = codebook->y2;
 215                     s->frame.data[0][iy[1] + 1] = codebook->y3;
 216                     if (!s->palette_video) {
 217                         s->frame.data[1][iu[0]] = codebook->u;
 218                         s->frame.data[2][iv[0]] = codebook->v;
 219                     }
 220
 221                     codebook = &strip->v4_codebook[*data++];
 222                     s->frame.data[0][iy[0] + 2] = codebook->y0;
 223                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 224                     s->frame.data[0][iy[1] + 2] = codebook->y2;
 225                     s->frame.data[0][iy[1] + 3] = codebook->y3;
 226                     if (!s->palette_video) {
 227                         s->frame.data[1][iu[0] + 1] = codebook->u;
 228                         s->frame.data[2][iv[0] + 1] = codebook->v;
 229                     }
 230
 231                     codebook = &strip->v4_codebook[*data++];
 232                     s->frame.data[0][iy[2] + 0] = codebook->y0;
 233                     s->frame.data[0][iy[2] + 1] = codebook->y1;
 234                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 235                     s->frame.data[0][iy[3] + 1] = codebook->y3;
 236                     if (!s->palette_video) {
 237                         s->frame.data[1][iu[1]] = codebook->u;
 238                         s->frame.data[2][iv[1]] = codebook->v;
 239                     }
 240
 241                     codebook = &strip->v4_codebook[*data++];
 242                     s->frame.data[0][iy[2] + 2] = codebook->y0;
 243                     s->frame.data[0][iy[2] + 3] = codebook->y1;
 244                     s->frame.data[0][iy[3] + 2] = codebook->y2;
 245                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 246                     if (!s->palette_video) {
 247                         s->frame.data[1][iu[1] + 1] = codebook->u;
 248                         s->frame.data[2][iv[1] + 1] = codebook->v;
 249                     }
 250
 251                 }
 252             }
 253
 254             iy[0] += 4;  iy[1] += 4;
 255             iy[2] += 4;  iy[3] += 4;
 256             iu[0] += 2;  iu[1] += 2;
 257             iv[0] += 2;  iv[1] += 2;
 258         }
 259     }
 260
 261     return 0;
 262 }
 263
 264 static int cinepak_decode_strip (CinepakContext *s,
 265                                  cvid_strip_t *strip, uint8_t *data, int size)
 266 {
 267     uint8_t *eod = (data + size);
 268     int      chunk_id, chunk_size;
 269
 270     /* coordinate sanity checks */
 271     if (strip->x1 >= s->width  || strip->x2 > s->width  ||
 272         strip->y1 >= s->height || strip->y2 > s->height ||
 273         strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
 274         return -1;
 275
 276     while ((data + 4) <= eod) {
 277         chunk_id   = BE_16 (&data[0]);
 278         chunk_size = BE_16 (&data[2]) - 4;
 279         if(chunk_size < 0)
 280             return -1;
 281
 282         data      += 4;
 283         chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
 284
 285         switch (chunk_id) {
 286
 287         case 0x2000:
 288         case 0x2100:
 289         case 0x2400:
 290         case 0x2500:
 291             cinepak_decode_codebook (strip->v4_codebook, chunk_id,
 292                 chunk_size, data);
 293             break;
 294
 295         case 0x2200:
 296         case 0x2300:
 297         case 0x2600:
 298         case 0x2700:
 299             cinepak_decode_codebook (strip->v1_codebook, chunk_id,
 300                 chunk_size, data);
 301             break;
 302
 303         case 0x3000:
 304         case 0x3100:
 305         case 0x3200:
 306             return cinepak_decode_vectors (s, strip, chunk_id,
 307                 chunk_size, data);
 308         }
 309
 310         data += chunk_size;
 311     }
 312
 313     return -1;
 314 }
 315
 316 static int cinepak_decode (CinepakContext *s)
 317 {
 318     uint8_t      *eod = (s->data + s->size);
 319     int           i, result, strip_size, frame_flags, num_strips;
 320     int           y0 = 0;
 321     int           encoded_buf_size;
 322     /* if true, Cinepak data is from a Sega FILM/CPK file */
 323     int           sega_film_data = 0;
 324
 325     if (s->size < 10)
 326         return -1;
 327
 328     frame_flags = s->data[0];
 329     num_strips  = BE_16 (&s->data[8]);
 330     encoded_buf_size = ((s->data[1] << 16) | BE_16 (&s->data[2]));
 331     if (encoded_buf_size != s->size)
 332         sega_film_data = 1;
 333     if (sega_film_data)
 334         s->data    += 12;
 335     else
 336         s->data    += 10;
 337
 338     if (num_strips > MAX_STRIPS)
 339         num_strips = MAX_STRIPS;
 340
 341     for (i=0; i < num_strips; i++) {
 342         if ((s->data + 12) > eod)
 343             return -1;
 344
 345         s->strips[i].id = BE_16 (s->data);
 346         s->strips[i].y1 = y0;
 347         s->strips[i].x1 = 0;
 348         s->strips[i].y2 = y0 + BE_16 (&s->data[8]);
 349         s->strips[i].x2 = s->avctx->width;
 350
 351         strip_size = BE_16 (&s->data[2]) - 12;
 352         s->data   += 12;
 353         strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
 354
 355         if ((i > 0) && !(frame_flags & 0x01)) {
 356             memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
 357                 sizeof(s->strips[i].v4_codebook));
 358             memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
 359                 sizeof(s->strips[i].v1_codebook));
 360         }
 361
 362         result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
 363
 364         if (result != 0)
 365             return result;
 366
 367         s->data += strip_size;
 368         y0    = s->strips[i].y2;
 369     }
 370     return 0;
 371 }
 372
 373 static int cinepak_decode_init(AVCodecContext *avctx)
 374 {
 375     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 376
 377     s->avctx = avctx;
 378     s->width = (avctx->width + 3) & ~3;
 379     s->height = (avctx->height + 3) & ~3;
 380
 381     // check for paletted data
 382     if ((avctx->palctrl == NULL) || (avctx->bits_per_sample == 40)) {
 383         s->palette_video = 0;
 384         avctx->pix_fmt = PIX_FMT_YUV420P;
 385     } else {
 386         s->palette_video = 1;
 387         avctx->pix_fmt = PIX_FMT_PAL8;
 388     }
 389
 390     avctx->has_b_frames = 0;
 391     dsputil_init(&s->dsp, avctx);
 392
 393     s->frame.data[0] = NULL;
 394
 395     return 0;
 396 }
 397
 398 static int cinepak_decode_frame(AVCodecContext *avctx,
 399                                 void *data, int *data_size,
 400                                 uint8_t *buf, int buf_size)
 401 {
 402     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 403
 404     s->data = buf;
 405     s->size = buf_size;
 406
 407     s->frame.reference = 1;
 408     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
 409                             FF_BUFFER_HINTS_REUSABLE;
 410     if (avctx->reget_buffer(avctx, &s->frame)) {
 411         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 412         return -1;
 413     }
 414
 415     cinepak_decode(s);
 416
 417     if (s->palette_video) {
 418         memcpy (s->frame.data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
 419         if (avctx->palctrl->palette_changed) {
 420             s->frame.palette_has_changed = 1;
 421             avctx->palctrl->palette_changed = 0;
 422         } else
 423             s->frame.palette_has_changed = 0;
 424     }
 425
 426     *data_size = sizeof(AVFrame);
 427     *(AVFrame*)data = s->frame;
 428
 429     /* report that the buffer was completely consumed */
 430     return buf_size;
 431 }
 432
 433 static int cinepak_decode_end(AVCodecContext *avctx)
 434 {
 435     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 436
 437     if (s->frame.data[0])
 438         avctx->release_buffer(avctx, &s->frame);
 439
 440     return 0;
 441 }
 442
 443 AVCodec cinepak_decoder = {
 444     "cinepak",
 445     CODEC_TYPE_VIDEO,
 446     CODEC_ID_CINEPAK,
 447     sizeof(CinepakContext),
 448     cinepak_decode_init,
 449     NULL,
 450     cinepak_decode_end,
 451     cinepak_decode_frame,
 452     CODEC_CAP_DR1,
 453 };