git.sesse.net Git - ffmpeg/blob - libavcodec/cinepak.c

   1 /*
   2  * Cinepak Video Decoder
   3  * Copyright (C) 2003 the ffmpeg project
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  */
  20
  21 /**
  22  * @file cinepak.c
  23  * Cinepak video decoder
  24  * by Ewald Snel <ewald@rambo.its.tudelft.nl>
  25  * For more information on the Cinepak algorithm, visit:
  26  *   http://www.csse.monash.edu.au/~timf/
  27  */
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <unistd.h>
  33
  34 #include "common.h"
  35 #include "avcodec.h"
  36 #include "dsputil.h"
  37
  38 #define PALETTE_COUNT 256
  39
  40 #define BE_16(x)  ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
  41 #define BE_32(x)  ((((uint8_t*)(x))[0] << 24) | \
  42                    (((uint8_t*)(x))[1] << 16) | \
  43                    (((uint8_t*)(x))[2] << 8) | \
  44                     ((uint8_t*)(x))[3])
  45
  46 typedef struct {
  47     uint8_t  y0, y1, y2, y3;
  48     uint8_t  u, v;
  49 } cvid_codebook_t;
  50
  51 #define MAX_STRIPS      32
  52
  53 typedef struct {
  54     uint16_t          id;
  55     uint16_t          x1, y1;
  56     uint16_t          x2, y2;
  57     cvid_codebook_t   v4_codebook[256];
  58     cvid_codebook_t   v1_codebook[256];
  59 } cvid_strip_t;
  60
  61 typedef struct CinepakContext {
  62
  63     AVCodecContext *avctx;
  64     DSPContext dsp;
  65     AVFrame frame;
  66     AVFrame prev_frame;
  67
  68     unsigned char *data;
  69     int size;
  70
  71     int width, height;
  72
  73     unsigned char palette[PALETTE_COUNT * 4];
  74     int palette_video;
  75     cvid_strip_t strips[MAX_STRIPS];
  76
  77 } CinepakContext;
  78
  79 static void cinepak_decode_codebook (cvid_codebook_t *codebook,
  80                                      int chunk_id, int size, uint8_t *data)
  81 {
  82     uint8_t *eod = (data + size);
  83     uint32_t flag, mask;
  84     int      i, n;
  85
  86     /* check if this chunk contains 4- or 6-element vectors */
  87     n    = (chunk_id & 0x0400) ? 4 : 6;
  88     flag = 0;
  89     mask = 0;
  90
  91     for (i=0; i < 256; i++) {
  92         if ((chunk_id & 0x0100) && !(mask >>= 1)) {
  93             if ((data + 4) > eod)
  94                 break;
  95
  96             flag  = BE_32 (data);
  97             data += 4;
  98             mask  = 0x80000000;
  99         }
 100
 101         if (!(chunk_id & 0x0100) || (flag & mask)) {
 102             if ((data + n) > eod)
 103                 break;
 104
 105             if (n == 6) {
 106                 codebook[i].y0 = *data++;
 107                 codebook[i].y1 = *data++;
 108                 codebook[i].y2 = *data++;
 109                 codebook[i].y3 = *data++;
 110                 codebook[i].u  = 128 + *data++;
 111                 codebook[i].v  = 128 + *data++;
 112             } else {
 113                 /* this codebook type indicates either greyscale or
 114                  * palettized video; if palettized, U & V components will
 115                  * not be used so it is safe to set them to 128 for the
 116                  * benefit of greyscale rendering in YUV420P */
 117                 codebook[i].y0 = *data++;
 118                 codebook[i].y1 = *data++;
 119                 codebook[i].y2 = *data++;
 120                 codebook[i].y3 = *data++;
 121                 codebook[i].u  = 128;
 122                 codebook[i].v  = 128;
 123             }
 124         }
 125     }
 126 }
 127
 128 static int cinepak_decode_vectors (CinepakContext *s, cvid_strip_t *strip,
 129                                    int chunk_id, int size, uint8_t *data)
 130 {
 131     uint8_t         *eod = (data + size);
 132     uint32_t         flag, mask;
 133     cvid_codebook_t *codebook;
 134     unsigned int     i, j, x, y;
 135     uint32_t         iy[4];
 136     uint32_t         iu[2];
 137     uint32_t         iv[2];
 138
 139     flag = 0;
 140     mask = 0;
 141
 142     for (y=strip->y1; y < strip->y2; y+=4) {
 143
 144         iy[0] = strip->x1 + (y * s->frame.linesize[0]);
 145         iy[1] = iy[0] + s->frame.linesize[0];
 146         iy[2] = iy[1] + s->frame.linesize[0];
 147         iy[3] = iy[2] + s->frame.linesize[0];
 148         iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]);
 149         iu[1] = iu[0] + s->frame.linesize[1];
 150         iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]);
 151         iv[1] = iv[0] + s->frame.linesize[2];
 152
 153         for (x=strip->x1; x < strip->x2; x+=4) {
 154             if ((chunk_id & 0x0100) && !(mask >>= 1)) {
 155                 if ((data + 4) > eod)
 156                     return -1;
 157
 158                 flag  = BE_32 (data);
 159                 data += 4;
 160                 mask  = 0x80000000;
 161             }
 162
 163             if (!(chunk_id & 0x0100) || (flag & mask)) {
 164                 if (!(chunk_id & 0x0200) && !(mask >>= 1)) {
 165                     if ((data + 4) > eod)
 166                         return -1;
 167
 168                     flag  = BE_32 (data);
 169                     data += 4;
 170                     mask  = 0x80000000;
 171                 }
 172
 173                 if ((chunk_id & 0x0200) || (~flag & mask)) {
 174                     if (data >= eod)
 175                         return -1;
 176
 177                     codebook = &strip->v1_codebook[*data++];
 178                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 179                     s->frame.data[0][iy[0] + 1] = codebook->y0;
 180                     s->frame.data[0][iy[1] + 0] = codebook->y0;
 181                     s->frame.data[0][iy[1] + 1] = codebook->y0;
 182                     if (!s->palette_video) {
 183                         s->frame.data[1][iu[0]] = codebook->u;
 184                         s->frame.data[2][iv[0]] = codebook->v;
 185                     }
 186
 187                     s->frame.data[0][iy[0] + 2] = codebook->y0;
 188                     s->frame.data[0][iy[0] + 3] = codebook->y0;
 189                     s->frame.data[0][iy[1] + 2] = codebook->y0;
 190                     s->frame.data[0][iy[1] + 3] = codebook->y0;
 191                     if (!s->palette_video) {
 192                         s->frame.data[1][iu[0] + 1] = codebook->u;
 193                         s->frame.data[2][iv[0] + 1] = codebook->v;
 194                     }
 195
 196                     s->frame.data[0][iy[2] + 0] = codebook->y0;
 197                     s->frame.data[0][iy[2] + 1] = codebook->y0;
 198                     s->frame.data[0][iy[3] + 0] = codebook->y0;
 199                     s->frame.data[0][iy[3] + 1] = codebook->y0;
 200                     if (!s->palette_video) {
 201                         s->frame.data[1][iu[1]] = codebook->u;
 202                         s->frame.data[2][iv[1]] = codebook->v;
 203                     }
 204
 205                     s->frame.data[0][iy[2] + 2] = codebook->y0;
 206                     s->frame.data[0][iy[2] + 3] = codebook->y0;
 207                     s->frame.data[0][iy[3] + 2] = codebook->y0;
 208                     s->frame.data[0][iy[3] + 3] = codebook->y0;
 209                     if (!s->palette_video) {
 210                         s->frame.data[1][iu[1] + 1] = codebook->u;
 211                         s->frame.data[2][iv[1] + 1] = codebook->v;
 212                     }
 213
 214                 } else if (flag & mask) {
 215                     if ((data + 4) > eod)
 216                         return -1;
 217
 218                     codebook = &strip->v4_codebook[*data++];
 219                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 220                     s->frame.data[0][iy[0] + 1] = codebook->y1;
 221                     s->frame.data[0][iy[1] + 0] = codebook->y2;
 222                     s->frame.data[0][iy[1] + 1] = codebook->y3;
 223                     if (!s->palette_video) {
 224                         s->frame.data[1][iu[0]] = codebook->u;
 225                         s->frame.data[2][iv[0]] = codebook->v;
 226                     }
 227
 228                     codebook = &strip->v4_codebook[*data++];
 229                     s->frame.data[0][iy[0] + 2] = codebook->y0;
 230                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 231                     s->frame.data[0][iy[1] + 2] = codebook->y2;
 232                     s->frame.data[0][iy[1] + 3] = codebook->y3;
 233                     if (!s->palette_video) {
 234                         s->frame.data[1][iu[0] + 1] = codebook->u;
 235                         s->frame.data[2][iv[0] + 1] = codebook->v;
 236                     }
 237
 238                     codebook = &strip->v4_codebook[*data++];
 239                     s->frame.data[0][iy[2] + 0] = codebook->y0;
 240                     s->frame.data[0][iy[2] + 1] = codebook->y1;
 241                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 242                     s->frame.data[0][iy[3] + 1] = codebook->y3;
 243                     if (!s->palette_video) {
 244                         s->frame.data[1][iu[1]] = codebook->u;
 245                         s->frame.data[2][iv[1]] = codebook->v;
 246                     }
 247
 248                     codebook = &strip->v4_codebook[*data++];
 249                     s->frame.data[0][iy[2] + 2] = codebook->y0;
 250                     s->frame.data[0][iy[2] + 3] = codebook->y1;
 251                     s->frame.data[0][iy[3] + 2] = codebook->y2;
 252                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 253                     if (!s->palette_video) {
 254                         s->frame.data[1][iu[1] + 1] = codebook->u;
 255                         s->frame.data[2][iv[1] + 1] = codebook->v;
 256                     }
 257
 258                 }
 259             } else {
 260                 /* copy from the previous frame */
 261                 for (i = 0; i < 4; i++) {
 262                     for (j = 0; j < 4; j++) {
 263                         s->frame.data[0][iy[i] + j] =
 264                             s->prev_frame.data[0][iy[i] + j];
 265                     }
 266                 }
 267                 for (i = 0; i < 2; i++) {
 268                     for (j = 0; j < 2; j++) {
 269                         s->frame.data[1][iu[i] + j] =
 270                             s->prev_frame.data[1][iu[i] + j];
 271                         s->frame.data[2][iv[i] + j] =
 272                             s->prev_frame.data[2][iv[i] + j];
 273                     }
 274                 }
 275             }
 276
 277             iy[0] += 4;  iy[1] += 4;
 278             iy[2] += 4;  iy[3] += 4;
 279             iu[0] += 2;  iu[1] += 2;
 280             iv[0] += 2;  iv[1] += 2;
 281         }
 282     }
 283
 284     return 0;
 285 }
 286
 287 static int cinepak_decode_strip (CinepakContext *s,
 288                                  cvid_strip_t *strip, uint8_t *data, int size)
 289 {
 290     uint8_t *eod = (data + size);
 291     int      chunk_id, chunk_size;
 292
 293     /* coordinate sanity checks */
 294     if (strip->x1 >= s->width  || strip->x2 > s->width  ||
 295         strip->y1 >= s->height || strip->y2 > s->height ||
 296         strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
 297         return -1;
 298
 299     while ((data + 4) <= eod) {
 300         chunk_id   = BE_16 (&data[0]);
 301         chunk_size = BE_16 (&data[2]) - 4;
 302         data      += 4;
 303         chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
 304
 305         switch (chunk_id) {
 306
 307         case 0x2000:
 308         case 0x2100:
 309         case 0x2400:
 310         case 0x2500:
 311             cinepak_decode_codebook (strip->v4_codebook, chunk_id,
 312                 chunk_size, data);
 313             break;
 314
 315         case 0x2200:
 316         case 0x2300:
 317         case 0x2600:
 318         case 0x2700:
 319             cinepak_decode_codebook (strip->v1_codebook, chunk_id,
 320                 chunk_size, data);
 321             break;
 322
 323         case 0x3000:
 324         case 0x3100:
 325         case 0x3200:
 326             return cinepak_decode_vectors (s, strip, chunk_id,
 327                 chunk_size, data);
 328         }
 329
 330         data += chunk_size;
 331     }
 332
 333     return -1;
 334 }
 335
 336 static int cinepak_decode (CinepakContext *s)
 337 {
 338     uint8_t      *eod = (s->data + s->size);
 339     int           i, result, strip_size, frame_flags, num_strips;
 340     int           y0 = 0;
 341
 342     if (s->size < 10)
 343         return -1;
 344
 345     frame_flags = s->data[0];
 346     num_strips  = BE_16 (&s->data[8]);
 347     s->data    += 10;
 348
 349     if (num_strips > MAX_STRIPS)
 350         num_strips = MAX_STRIPS;
 351
 352     for (i=0; i < num_strips; i++) {
 353         if ((s->data + 12) > eod)
 354             return -1;
 355
 356         s->strips[i].id = BE_16 (s->data);
 357         s->strips[i].y1 = y0;
 358         s->strips[i].x1 = 0;
 359         s->strips[i].y2 = y0 + BE_16 (&s->data[8]);
 360         s->strips[i].x2 = s->avctx->width;
 361
 362         strip_size = BE_16 (&s->data[2]) - 12;
 363         s->data   += 12;
 364         strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
 365
 366         if ((i > 0) && !(frame_flags & 0x01)) {
 367             memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
 368                 sizeof(s->strips[i].v4_codebook));
 369             memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
 370                 sizeof(s->strips[i].v1_codebook));
 371         }
 372
 373         result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
 374
 375         if (result != 0)
 376             return result;
 377
 378         s->data += strip_size;
 379         y0    = s->strips[i].y2;
 380     }
 381     return 0;
 382 }
 383
 384 static int cinepak_decode_init(AVCodecContext *avctx)
 385 {
 386     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 387 /*
 388     int i;
 389     unsigned char r, g, b;
 390     unsigned char *raw_palette;
 391     unsigned int *palette32;
 392 */
 393
 394     s->avctx = avctx;
 395     s->width = (avctx->width + 3) & ~3;
 396     s->height = (avctx->height + 3) & ~3;
 397
 398 // check for paletted data
 399 s->palette_video = 0;
 400
 401
 402     avctx->pix_fmt = PIX_FMT_YUV420P;
 403     avctx->has_b_frames = 0;
 404     dsputil_init(&s->dsp, avctx);
 405
 406     s->frame.data[0] = s->prev_frame.data[0] = NULL;
 407
 408     return 0;
 409 }
 410
 411 static int cinepak_decode_frame(AVCodecContext *avctx,
 412                                 void *data, int *data_size,
 413                                 uint8_t *buf, int buf_size)
 414 {
 415     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 416
 417     s->data = buf;
 418     s->size = buf_size;
 419
 420     if (avctx->get_buffer(avctx, &s->frame)) {
 421         av_log(avctx, AV_LOG_ERROR, "  Cinepak: get_buffer() failed\n");
 422         return -1;
 423     }
 424
 425     cinepak_decode(s);
 426
 427     if (s->prev_frame.data[0])
 428         avctx->release_buffer(avctx, &s->prev_frame);
 429
 430     /* shuffle frames */
 431     s->prev_frame = s->frame;
 432
 433     *data_size = sizeof(AVFrame);
 434     *(AVFrame*)data = s->frame;
 435
 436     /* report that the buffer was completely consumed */
 437     return buf_size;
 438 }
 439
 440 static int cinepak_decode_end(AVCodecContext *avctx)
 441 {
 442     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 443
 444     if (s->prev_frame.data[0])
 445         avctx->release_buffer(avctx, &s->prev_frame);
 446
 447     return 0;
 448 }
 449
 450 AVCodec cinepak_decoder = {
 451     "cinepak",
 452     CODEC_TYPE_VIDEO,
 453     CODEC_ID_CINEPAK,
 454     sizeof(CinepakContext),
 455     cinepak_decode_init,
 456     NULL,
 457     cinepak_decode_end,
 458     cinepak_decode_frame,
 459     CODEC_CAP_DR1,
 460 };