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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  * 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 #include <unistd.h>
  37
  38 #include "common.h"
  39 #include "avcodec.h"
  40 #include "dsputil.h"
  41
  42
  43 typedef struct {
  44     uint8_t  y0, y1, y2, y3;
  45     uint8_t  u, v;
  46 } cvid_codebook_t;
  47
  48 #define MAX_STRIPS      32
  49
  50 typedef struct {
  51     uint16_t          id;
  52     uint16_t          x1, y1;
  53     uint16_t          x2, y2;
  54     cvid_codebook_t   v4_codebook[256];
  55     cvid_codebook_t   v1_codebook[256];
  56 } cvid_strip_t;
  57
  58 typedef struct CinepakContext {
  59
  60     AVCodecContext *avctx;
  61     DSPContext dsp;
  62     AVFrame frame;
  63
  64     unsigned char *data;
  65     int size;
  66
  67     int width, height;
  68
  69     int palette_video;
  70     cvid_strip_t strips[MAX_STRIPS];
  71
  72     int sega_film_skip_bytes;
  73
  74 } CinepakContext;
  75
  76 static void cinepak_decode_codebook (cvid_codebook_t *codebook,
  77                                      int chunk_id, int size, uint8_t *data)
  78 {
  79     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 & 0x0400) ? 4 : 6;
  85     flag = 0;
  86     mask = 0;
  87
  88     for (i=0; i < 256; i++) {
  89         if ((chunk_id & 0x0100) && !(mask >>= 1)) {
  90             if ((data + 4) > eod)
  91                 break;
  92
  93             flag  = BE_32 (data);
  94             data += 4;
  95             mask  = 0x80000000;
  96         }
  97
  98         if (!(chunk_id & 0x0100) || (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_t *strip,
 126                                    int chunk_id, int size, uint8_t *data)
 127 {
 128     uint8_t         *eod = (data + size);
 129     uint32_t         flag, mask;
 130     cvid_codebook_t *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 & 0x0100) && !(mask >>= 1)) {
 152                 if ((data + 4) > eod)
 153                     return -1;
 154
 155                 flag  = BE_32 (data);
 156                 data += 4;
 157                 mask  = 0x80000000;
 158             }
 159
 160             if (!(chunk_id & 0x0100) || (flag & mask)) {
 161                 if (!(chunk_id & 0x0200) && !(mask >>= 1)) {
 162                     if ((data + 4) > eod)
 163                         return -1;
 164
 165                     flag  = BE_32 (data);
 166                     data += 4;
 167                     mask  = 0x80000000;
 168                 }
 169
 170                 if ((chunk_id & 0x0200) || (~flag & mask)) {
 171                     if (data >= eod)
 172                         return -1;
 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 -1;
 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_t *strip, uint8_t *data, int size)
 270 {
 271     uint8_t *eod = (data + size);
 272     int      chunk_id, chunk_size;
 273
 274     /* coordinate sanity checks */
 275     if (strip->x1 >= s->width  || strip->x2 > s->width  ||
 276         strip->y1 >= s->height || strip->y2 > s->height ||
 277         strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
 278         return -1;
 279
 280     while ((data + 4) <= eod) {
 281         chunk_id   = BE_16 (&data[0]);
 282         chunk_size = BE_16 (&data[2]) - 4;
 283         if(chunk_size < 0)
 284             return -1;
 285
 286         data      += 4;
 287         chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
 288
 289         switch (chunk_id) {
 290
 291         case 0x2000:
 292         case 0x2100:
 293         case 0x2400:
 294         case 0x2500:
 295             cinepak_decode_codebook (strip->v4_codebook, chunk_id,
 296                 chunk_size, data);
 297             break;
 298
 299         case 0x2200:
 300         case 0x2300:
 301         case 0x2600:
 302         case 0x2700:
 303             cinepak_decode_codebook (strip->v1_codebook, chunk_id,
 304                 chunk_size, data);
 305             break;
 306
 307         case 0x3000:
 308         case 0x3100:
 309         case 0x3200:
 310             return cinepak_decode_vectors (s, strip, chunk_id,
 311                 chunk_size, data);
 312         }
 313
 314         data += chunk_size;
 315     }
 316
 317     return -1;
 318 }
 319
 320 static int cinepak_decode (CinepakContext *s)
 321 {
 322     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 -1;
 329
 330     frame_flags = s->data[0];
 331     num_strips  = BE_16 (&s->data[8]);
 332     encoded_buf_size = ((s->data[1] << 16) | BE_16 (&s->data[2]));
 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 != s->size) {
 337             /* If the encoded frame size differs from the frame size as indicated
 338              * by the container file, this data likely comes from a Sega FILM/CPK file.
 339              * If the frame header is followed by the bytes FE 00 00 06 00 00 then
 340              * this is probably one of the two known files that have 6 extra bytes
 341              * after the frame header. Else, assume 2 extra bytes. */
 342             if ((s->data[10] == 0xFE) &&
 343                 (s->data[11] == 0x00) &&
 344                 (s->data[12] == 0x00) &&
 345                 (s->data[13] == 0x06) &&
 346                 (s->data[14] == 0x00) &&
 347                 (s->data[15] == 0x00))
 348                 s->sega_film_skip_bytes = 6;
 349             else
 350                 s->sega_film_skip_bytes = 2;
 351         } else
 352             s->sega_film_skip_bytes = 0;
 353     }
 354
 355     s->data += 10 + s->sega_film_skip_bytes;
 356
 357     if (num_strips > MAX_STRIPS)
 358         num_strips = MAX_STRIPS;
 359
 360     for (i=0; i < num_strips; i++) {
 361         if ((s->data + 12) > eod)
 362             return -1;
 363
 364         s->strips[i].id = BE_16 (s->data);
 365         s->strips[i].y1 = y0;
 366         s->strips[i].x1 = 0;
 367         s->strips[i].y2 = y0 + BE_16 (&s->data[8]);
 368         s->strips[i].x2 = s->avctx->width;
 369
 370         strip_size = BE_16 (&s->data[2]) - 12;
 371         s->data   += 12;
 372         strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
 373
 374         if ((i > 0) && !(frame_flags & 0x01)) {
 375             memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
 376                 sizeof(s->strips[i].v4_codebook));
 377             memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
 378                 sizeof(s->strips[i].v1_codebook));
 379         }
 380
 381         result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
 382
 383         if (result != 0)
 384             return result;
 385
 386         s->data += strip_size;
 387         y0    = s->strips[i].y2;
 388     }
 389     return 0;
 390 }
 391
 392 static int cinepak_decode_init(AVCodecContext *avctx)
 393 {
 394     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 395
 396     s->avctx = avctx;
 397     s->width = (avctx->width + 3) & ~3;
 398     s->height = (avctx->height + 3) & ~3;
 399     s->sega_film_skip_bytes = -1;  /* uninitialized state */
 400
 401     // check for paletted data
 402     if ((avctx->palctrl == NULL) || (avctx->bits_per_sample == 40)) {
 403         s->palette_video = 0;
 404         avctx->pix_fmt = PIX_FMT_YUV420P;
 405     } else {
 406         s->palette_video = 1;
 407         avctx->pix_fmt = PIX_FMT_PAL8;
 408     }
 409
 410     avctx->has_b_frames = 0;
 411     dsputil_init(&s->dsp, avctx);
 412
 413     s->frame.data[0] = NULL;
 414
 415     return 0;
 416 }
 417
 418 static int cinepak_decode_frame(AVCodecContext *avctx,
 419                                 void *data, int *data_size,
 420                                 uint8_t *buf, int buf_size)
 421 {
 422     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 423
 424     s->data = buf;
 425     s->size = buf_size;
 426
 427     s->frame.reference = 1;
 428     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
 429                             FF_BUFFER_HINTS_REUSABLE;
 430     if (avctx->reget_buffer(avctx, &s->frame)) {
 431         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 432         return -1;
 433     }
 434
 435     cinepak_decode(s);
 436
 437     if (s->palette_video) {
 438         memcpy (s->frame.data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
 439         if (avctx->palctrl->palette_changed) {
 440             s->frame.palette_has_changed = 1;
 441             avctx->palctrl->palette_changed = 0;
 442         } else
 443             s->frame.palette_has_changed = 0;
 444     }
 445
 446     *data_size = sizeof(AVFrame);
 447     *(AVFrame*)data = s->frame;
 448
 449     /* report that the buffer was completely consumed */
 450     return buf_size;
 451 }
 452
 453 static int cinepak_decode_end(AVCodecContext *avctx)
 454 {
 455     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 456
 457     if (s->frame.data[0])
 458         avctx->release_buffer(avctx, &s->frame);
 459
 460     return 0;
 461 }
 462
 463 AVCodec cinepak_decoder = {
 464     "cinepak",
 465     CODEC_TYPE_VIDEO,
 466     CODEC_ID_CINEPAK,
 467     sizeof(CinepakContext),
 468     cinepak_decode_init,
 469     NULL,
 470     cinepak_decode_end,
 471     cinepak_decode_frame,
 472     CODEC_CAP_DR1,
 473 };