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
  39 typedef struct {
  40     uint8_t  y0, y1, y2, y3;
  41     uint8_t  u, v;
  42 } cvid_codebook_t;
  43
  44 #define MAX_STRIPS      32
  45
  46 typedef struct {
  47     uint16_t          id;
  48     uint16_t          x1, y1;
  49     uint16_t          x2, y2;
  50     cvid_codebook_t   v4_codebook[256];
  51     cvid_codebook_t   v1_codebook[256];
  52 } cvid_strip_t;
  53
  54 typedef struct CinepakContext {
  55
  56     AVCodecContext *avctx;
  57     DSPContext dsp;
  58     AVFrame frame;
  59
  60     unsigned char *data;
  61     int size;
  62
  63     int width, height;
  64
  65     int palette_video;
  66     cvid_strip_t strips[MAX_STRIPS];
  67
  68 } CinepakContext;
  69
  70 static void cinepak_decode_codebook (cvid_codebook_t *codebook,
  71                                      int chunk_id, int size, uint8_t *data)
  72 {
  73     uint8_t *eod = (data + size);
  74     uint32_t flag, mask;
  75     int      i, n;
  76
  77     /* check if this chunk contains 4- or 6-element vectors */
  78     n    = (chunk_id & 0x0400) ? 4 : 6;
  79     flag = 0;
  80     mask = 0;
  81
  82     for (i=0; i < 256; i++) {
  83         if ((chunk_id & 0x0100) && !(mask >>= 1)) {
  84             if ((data + 4) > eod)
  85                 break;
  86
  87             flag  = BE_32 (data);
  88             data += 4;
  89             mask  = 0x80000000;
  90         }
  91
  92         if (!(chunk_id & 0x0100) || (flag & mask)) {
  93             if ((data + n) > eod)
  94                 break;
  95
  96             if (n == 6) {
  97                 codebook[i].y0 = *data++;
  98                 codebook[i].y1 = *data++;
  99                 codebook[i].y2 = *data++;
 100                 codebook[i].y3 = *data++;
 101                 codebook[i].u  = 128 + *data++;
 102                 codebook[i].v  = 128 + *data++;
 103             } else {
 104                 /* this codebook type indicates either greyscale or
 105                  * palettized video; if palettized, U & V components will
 106                  * not be used so it is safe to set them to 128 for the
 107                  * benefit of greyscale rendering in YUV420P */
 108                 codebook[i].y0 = *data++;
 109                 codebook[i].y1 = *data++;
 110                 codebook[i].y2 = *data++;
 111                 codebook[i].y3 = *data++;
 112                 codebook[i].u  = 128;
 113                 codebook[i].v  = 128;
 114             }
 115         }
 116     }
 117 }
 118
 119 static int cinepak_decode_vectors (CinepakContext *s, cvid_strip_t *strip,
 120                                    int chunk_id, int size, uint8_t *data)
 121 {
 122     uint8_t         *eod = (data + size);
 123     uint32_t         flag, mask;
 124     cvid_codebook_t *codebook;
 125     unsigned int     x, y;
 126     uint32_t         iy[4];
 127     uint32_t         iu[2];
 128     uint32_t         iv[2];
 129
 130     flag = 0;
 131     mask = 0;
 132
 133     for (y=strip->y1; y < strip->y2; y+=4) {
 134
 135         iy[0] = strip->x1 + (y * s->frame.linesize[0]);
 136         iy[1] = iy[0] + s->frame.linesize[0];
 137         iy[2] = iy[1] + s->frame.linesize[0];
 138         iy[3] = iy[2] + s->frame.linesize[0];
 139         iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]);
 140         iu[1] = iu[0] + s->frame.linesize[1];
 141         iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]);
 142         iv[1] = iv[0] + s->frame.linesize[2];
 143
 144         for (x=strip->x1; x < strip->x2; x+=4) {
 145             if ((chunk_id & 0x0100) && !(mask >>= 1)) {
 146                 if ((data + 4) > eod)
 147                     return -1;
 148
 149                 flag  = BE_32 (data);
 150                 data += 4;
 151                 mask  = 0x80000000;
 152             }
 153
 154             if (!(chunk_id & 0x0100) || (flag & mask)) {
 155                 if (!(chunk_id & 0x0200) && !(mask >>= 1)) {
 156                     if ((data + 4) > eod)
 157                         return -1;
 158
 159                     flag  = BE_32 (data);
 160                     data += 4;
 161                     mask  = 0x80000000;
 162                 }
 163
 164                 if ((chunk_id & 0x0200) || (~flag & mask)) {
 165                     if (data >= eod)
 166                         return -1;
 167
 168                     codebook = &strip->v1_codebook[*data++];
 169                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 170                     s->frame.data[0][iy[0] + 1] = codebook->y0;
 171                     s->frame.data[0][iy[1] + 0] = codebook->y0;
 172                     s->frame.data[0][iy[1] + 1] = codebook->y0;
 173                     if (!s->palette_video) {
 174                         s->frame.data[1][iu[0]] = codebook->u;
 175                         s->frame.data[2][iv[0]] = codebook->v;
 176                     }
 177
 178                     s->frame.data[0][iy[0] + 2] = codebook->y1;
 179                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 180                     s->frame.data[0][iy[1] + 2] = codebook->y1;
 181                     s->frame.data[0][iy[1] + 3] = codebook->y1;
 182                     if (!s->palette_video) {
 183                         s->frame.data[1][iu[0] + 1] = codebook->u;
 184                         s->frame.data[2][iv[0] + 1] = codebook->v;
 185                     }
 186
 187                     s->frame.data[0][iy[2] + 0] = codebook->y2;
 188                     s->frame.data[0][iy[2] + 1] = codebook->y2;
 189                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 190                     s->frame.data[0][iy[3] + 1] = codebook->y2;
 191                     if (!s->palette_video) {
 192                         s->frame.data[1][iu[1]] = codebook->u;
 193                         s->frame.data[2][iv[1]] = codebook->v;
 194                     }
 195
 196                     s->frame.data[0][iy[2] + 2] = codebook->y3;
 197                     s->frame.data[0][iy[2] + 3] = codebook->y3;
 198                     s->frame.data[0][iy[3] + 2] = codebook->y3;
 199                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 200                     if (!s->palette_video) {
 201                         s->frame.data[1][iu[1] + 1] = codebook->u;
 202                         s->frame.data[2][iv[1] + 1] = codebook->v;
 203                     }
 204
 205                 } else if (flag & mask) {
 206                     if ((data + 4) > eod)
 207                         return -1;
 208
 209                     codebook = &strip->v4_codebook[*data++];
 210                     s->frame.data[0][iy[0] + 0] = codebook->y0;
 211                     s->frame.data[0][iy[0] + 1] = codebook->y1;
 212                     s->frame.data[0][iy[1] + 0] = codebook->y2;
 213                     s->frame.data[0][iy[1] + 1] = codebook->y3;
 214                     if (!s->palette_video) {
 215                         s->frame.data[1][iu[0]] = codebook->u;
 216                         s->frame.data[2][iv[0]] = codebook->v;
 217                     }
 218
 219                     codebook = &strip->v4_codebook[*data++];
 220                     s->frame.data[0][iy[0] + 2] = codebook->y0;
 221                     s->frame.data[0][iy[0] + 3] = codebook->y1;
 222                     s->frame.data[0][iy[1] + 2] = codebook->y2;
 223                     s->frame.data[0][iy[1] + 3] = codebook->y3;
 224                     if (!s->palette_video) {
 225                         s->frame.data[1][iu[0] + 1] = codebook->u;
 226                         s->frame.data[2][iv[0] + 1] = codebook->v;
 227                     }
 228
 229                     codebook = &strip->v4_codebook[*data++];
 230                     s->frame.data[0][iy[2] + 0] = codebook->y0;
 231                     s->frame.data[0][iy[2] + 1] = codebook->y1;
 232                     s->frame.data[0][iy[3] + 0] = codebook->y2;
 233                     s->frame.data[0][iy[3] + 1] = codebook->y3;
 234                     if (!s->palette_video) {
 235                         s->frame.data[1][iu[1]] = codebook->u;
 236                         s->frame.data[2][iv[1]] = codebook->v;
 237                     }
 238
 239                     codebook = &strip->v4_codebook[*data++];
 240                     s->frame.data[0][iy[2] + 2] = codebook->y0;
 241                     s->frame.data[0][iy[2] + 3] = codebook->y1;
 242                     s->frame.data[0][iy[3] + 2] = codebook->y2;
 243                     s->frame.data[0][iy[3] + 3] = codebook->y3;
 244                     if (!s->palette_video) {
 245                         s->frame.data[1][iu[1] + 1] = codebook->u;
 246                         s->frame.data[2][iv[1] + 1] = codebook->v;
 247                     }
 248
 249                 }
 250             }
 251
 252             iy[0] += 4;  iy[1] += 4;
 253             iy[2] += 4;  iy[3] += 4;
 254             iu[0] += 2;  iu[1] += 2;
 255             iv[0] += 2;  iv[1] += 2;
 256         }
 257     }
 258
 259     return 0;
 260 }
 261
 262 static int cinepak_decode_strip (CinepakContext *s,
 263                                  cvid_strip_t *strip, uint8_t *data, int size)
 264 {
 265     uint8_t *eod = (data + size);
 266     int      chunk_id, chunk_size;
 267
 268     /* coordinate sanity checks */
 269     if (strip->x1 >= s->width  || strip->x2 > s->width  ||
 270         strip->y1 >= s->height || strip->y2 > s->height ||
 271         strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
 272         return -1;
 273
 274     while ((data + 4) <= eod) {
 275         chunk_id   = BE_16 (&data[0]);
 276         chunk_size = BE_16 (&data[2]) - 4;
 277         data      += 4;
 278         chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
 279
 280         switch (chunk_id) {
 281
 282         case 0x2000:
 283         case 0x2100:
 284         case 0x2400:
 285         case 0x2500:
 286             cinepak_decode_codebook (strip->v4_codebook, chunk_id,
 287                 chunk_size, data);
 288             break;
 289
 290         case 0x2200:
 291         case 0x2300:
 292         case 0x2600:
 293         case 0x2700:
 294             cinepak_decode_codebook (strip->v1_codebook, chunk_id,
 295                 chunk_size, data);
 296             break;
 297
 298         case 0x3000:
 299         case 0x3100:
 300         case 0x3200:
 301             return cinepak_decode_vectors (s, strip, chunk_id,
 302                 chunk_size, data);
 303         }
 304
 305         data += chunk_size;
 306     }
 307
 308     return -1;
 309 }
 310
 311 static int cinepak_decode (CinepakContext *s)
 312 {
 313     uint8_t      *eod = (s->data + s->size);
 314     int           i, result, strip_size, frame_flags, num_strips;
 315     int           y0 = 0;
 316
 317     if (s->size < 10)
 318         return -1;
 319
 320     frame_flags = s->data[0];
 321     num_strips  = BE_16 (&s->data[8]);
 322     s->data    += 10;
 323
 324     if (num_strips > MAX_STRIPS)
 325         num_strips = MAX_STRIPS;
 326
 327     for (i=0; i < num_strips; i++) {
 328         if ((s->data + 12) > eod)
 329             return -1;
 330
 331         s->strips[i].id = BE_16 (s->data);
 332         s->strips[i].y1 = y0;
 333         s->strips[i].x1 = 0;
 334         s->strips[i].y2 = y0 + BE_16 (&s->data[8]);
 335         s->strips[i].x2 = s->avctx->width;
 336
 337         strip_size = BE_16 (&s->data[2]) - 12;
 338         s->data   += 12;
 339         strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
 340
 341         if ((i > 0) && !(frame_flags & 0x01)) {
 342             memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
 343                 sizeof(s->strips[i].v4_codebook));
 344             memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
 345                 sizeof(s->strips[i].v1_codebook));
 346         }
 347
 348         result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
 349
 350         if (result != 0)
 351             return result;
 352
 353         s->data += strip_size;
 354         y0    = s->strips[i].y2;
 355     }
 356     return 0;
 357 }
 358
 359 static int cinepak_decode_init(AVCodecContext *avctx)
 360 {
 361     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 362
 363     s->avctx = avctx;
 364     s->width = (avctx->width + 3) & ~3;
 365     s->height = (avctx->height + 3) & ~3;
 366
 367     // check for paletted data
 368     if ((avctx->palctrl == NULL) || (avctx->bits_per_sample == 40)) {
 369         s->palette_video = 0;
 370         avctx->pix_fmt = PIX_FMT_YUV420P;
 371     } else {
 372         s->palette_video = 1;
 373         avctx->pix_fmt = PIX_FMT_PAL8;
 374     }
 375
 376     avctx->has_b_frames = 0;
 377     dsputil_init(&s->dsp, avctx);
 378
 379     s->frame.data[0] = NULL;
 380
 381     return 0;
 382 }
 383
 384 static int cinepak_decode_frame(AVCodecContext *avctx,
 385                                 void *data, int *data_size,
 386                                 uint8_t *buf, int buf_size)
 387 {
 388     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 389
 390     s->data = buf;
 391     s->size = buf_size;
 392
 393     s->frame.reference = 1;
 394     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
 395                             FF_BUFFER_HINTS_REUSABLE;
 396     if (avctx->reget_buffer(avctx, &s->frame)) {
 397         av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 398         return -1;
 399     }
 400
 401     cinepak_decode(s);
 402
 403     if (s->palette_video) {
 404         memcpy (s->frame.data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
 405         if (avctx->palctrl->palette_changed) {
 406             s->frame.palette_has_changed = 1;
 407             avctx->palctrl->palette_changed = 0;
 408         } else
 409             s->frame.palette_has_changed = 0;
 410     }
 411
 412     *data_size = sizeof(AVFrame);
 413     *(AVFrame*)data = s->frame;
 414
 415     /* report that the buffer was completely consumed */
 416     return buf_size;
 417 }
 418
 419 static int cinepak_decode_end(AVCodecContext *avctx)
 420 {
 421     CinepakContext *s = (CinepakContext *)avctx->priv_data;
 422
 423     if (s->frame.data[0])
 424         avctx->release_buffer(avctx, &s->frame);
 425
 426     return 0;
 427 }
 428
 429 AVCodec cinepak_decoder = {
 430     "cinepak",
 431     CODEC_TYPE_VIDEO,
 432     CODEC_ID_CINEPAK,
 433     sizeof(CinepakContext),
 434     cinepak_decode_init,
 435     NULL,
 436     cinepak_decode_end,
 437     cinepak_decode_frame,
 438     CODEC_CAP_DR1,
 439 };