vqavideo.c
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1 /*
2  * Westwood Studios VQA Video Decoder
3  * Copyright (C) 2003 the ffmpeg project
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
66 #include <stdio.h>
67 #include <stdlib.h>
68 #include <string.h>
69 
70 #include "libavutil/intreadwrite.h"
71 #include "libavutil/imgutils.h"
72 #include "avcodec.h"
73 #include "bytestream.h"
74 
75 #define PALETTE_COUNT 256
76 #define VQA_HEADER_SIZE 0x2A
77 
78 /* allocate the maximum vector space, regardless of the file version:
79  * (0xFF00 codebook vectors + 0x100 solid pixel vectors) * (4x4 pixels/block) */
80 #define MAX_CODEBOOK_VECTORS 0xFF00
81 #define SOLID_PIXEL_VECTORS 0x100
82 #define MAX_VECTORS (MAX_CODEBOOK_VECTORS + SOLID_PIXEL_VECTORS)
83 #define MAX_CODEBOOK_SIZE (MAX_VECTORS * 4 * 4)
84 
85 #define CBF0_TAG MKBETAG('C', 'B', 'F', '0')
86 #define CBFZ_TAG MKBETAG('C', 'B', 'F', 'Z')
87 #define CBP0_TAG MKBETAG('C', 'B', 'P', '0')
88 #define CBPZ_TAG MKBETAG('C', 'B', 'P', 'Z')
89 #define CPL0_TAG MKBETAG('C', 'P', 'L', '0')
90 #define CPLZ_TAG MKBETAG('C', 'P', 'L', 'Z')
91 #define VPTZ_TAG MKBETAG('V', 'P', 'T', 'Z')
92 
93 typedef struct VqaContext {
94 
98 
100 
101  int width; /* width of a frame */
102  int height; /* height of a frame */
103  int vector_width; /* width of individual vector */
104  int vector_height; /* height of individual vector */
105  int vqa_version; /* this should be either 1, 2 or 3 */
106 
107  unsigned char *codebook; /* the current codebook */
109  unsigned char *next_codebook_buffer; /* accumulator for next codebook */
111 
112  unsigned char *decode_buffer;
114 
115  /* number of frames to go before replacing codebook */
118 
119 } VqaContext;
120 
122 {
123  VqaContext *s = avctx->priv_data;
124  int i, j, codebook_index;
125 
126  s->avctx = avctx;
127  avctx->pix_fmt = PIX_FMT_PAL8;
128 
129  /* make sure the extradata made it */
130  if (s->avctx->extradata_size != VQA_HEADER_SIZE) {
131  av_log(s->avctx, AV_LOG_ERROR, " VQA video: expected extradata size of %d\n", VQA_HEADER_SIZE);
132  return -1;
133  }
134 
135  /* load up the VQA parameters from the header */
136  s->vqa_version = s->avctx->extradata[0];
137  s->width = AV_RL16(&s->avctx->extradata[6]);
138  s->height = AV_RL16(&s->avctx->extradata[8]);
139  if(av_image_check_size(s->width, s->height, 0, avctx)){
140  s->width= s->height= 0;
141  return -1;
142  }
143  s->vector_width = s->avctx->extradata[10];
144  s->vector_height = s->avctx->extradata[11];
146 
147  /* the vector dimensions have to meet very stringent requirements */
148  if ((s->vector_width != 4) ||
149  ((s->vector_height != 2) && (s->vector_height != 4))) {
150  /* return without further initialization */
151  return -1;
152  }
153 
154  if (s->width & (s->vector_width - 1) ||
155  s->height & (s->vector_height - 1)) {
156  av_log(avctx, AV_LOG_ERROR, "Image size not multiple of block size\n");
157  return AVERROR_INVALIDDATA;
158  }
159 
160  /* allocate codebooks */
164 
165  /* initialize the solid-color vectors */
166  if (s->vector_height == 4) {
167  codebook_index = 0xFF00 * 16;
168  for (i = 0; i < 256; i++)
169  for (j = 0; j < 16; j++)
170  s->codebook[codebook_index++] = i;
171  } else {
172  codebook_index = 0xF00 * 8;
173  for (i = 0; i < 256; i++)
174  for (j = 0; j < 8; j++)
175  s->codebook[codebook_index++] = i;
176  }
178 
179  /* allocate decode buffer */
180  s->decode_buffer_size = (s->width / s->vector_width) *
181  (s->height / s->vector_height) * 2;
183 
184  s->frame.data[0] = NULL;
185 
186  return 0;
187 }
188 
189 #define CHECK_COUNT() \
190  if (dest_index + count > dest_size) { \
191  av_log(NULL, AV_LOG_ERROR, " VQA video: decode_format80 problem: next op would overflow dest_index\n"); \
192  av_log(NULL, AV_LOG_ERROR, " VQA video: current dest_index = %d, count = %d, dest_size = %d\n", \
193  dest_index, count, dest_size); \
194  return AVERROR_INVALIDDATA; \
195  }
196 
197 #define CHECK_COPY(idx) \
198  if (idx < 0 || idx + count > dest_size) { \
199  av_log(NULL, AV_LOG_ERROR, " VQA video: decode_format80 problem: next op would overflow dest_index\n"); \
200  av_log(NULL, AV_LOG_ERROR, " VQA video: current src_pos = %d, count = %d, dest_size = %d\n", \
201  src_pos, count, dest_size); \
202  return AVERROR_INVALIDDATA; \
203  }
204 
205 
206 static int decode_format80(GetByteContext *gb, int src_size,
207  unsigned char *dest, int dest_size, int check_size) {
208 
209  int dest_index = 0;
210  int count, opcode, start;
211  int src_pos;
212  unsigned char color;
213  int i;
214 
215  start = bytestream2_tell(gb);
216  while (bytestream2_tell(gb) - start < src_size) {
217  opcode = bytestream2_get_byte(gb);
218  av_dlog(NULL, " opcode %02X: ", opcode);
219 
220  /* 0x80 means that frame is finished */
221  if (opcode == 0x80)
222  return 0;
223 
224  if (dest_index >= dest_size) {
225  av_log(NULL, AV_LOG_ERROR, " VQA video: decode_format80 problem: dest_index (%d) exceeded dest_size (%d)\n",
226  dest_index, dest_size);
227  return AVERROR_INVALIDDATA;
228  }
229 
230  if (opcode == 0xFF) {
231 
232  count = bytestream2_get_le16(gb);
233  src_pos = bytestream2_get_le16(gb);
234  av_dlog(NULL, "(1) copy %X bytes from absolute pos %X\n", count, src_pos);
235  CHECK_COUNT();
236  CHECK_COPY(src_pos);
237  for (i = 0; i < count; i++)
238  dest[dest_index + i] = dest[src_pos + i];
239  dest_index += count;
240 
241  } else if (opcode == 0xFE) {
242 
243  count = bytestream2_get_le16(gb);
244  color = bytestream2_get_byte(gb);
245  av_dlog(NULL, "(2) set %X bytes to %02X\n", count, color);
246  CHECK_COUNT();
247  memset(&dest[dest_index], color, count);
248  dest_index += count;
249 
250  } else if ((opcode & 0xC0) == 0xC0) {
251 
252  count = (opcode & 0x3F) + 3;
253  src_pos = bytestream2_get_le16(gb);
254  av_dlog(NULL, "(3) copy %X bytes from absolute pos %X\n", count, src_pos);
255  CHECK_COUNT();
256  CHECK_COPY(src_pos);
257  for (i = 0; i < count; i++)
258  dest[dest_index + i] = dest[src_pos + i];
259  dest_index += count;
260 
261  } else if (opcode > 0x80) {
262 
263  count = opcode & 0x3F;
264  av_dlog(NULL, "(4) copy %X bytes from source to dest\n", count);
265  CHECK_COUNT();
266  bytestream2_get_buffer(gb, &dest[dest_index], count);
267  dest_index += count;
268 
269  } else {
270 
271  count = ((opcode & 0x70) >> 4) + 3;
272  src_pos = bytestream2_get_byte(gb) | ((opcode & 0x0F) << 8);
273  av_dlog(NULL, "(5) copy %X bytes from relpos %X\n", count, src_pos);
274  CHECK_COUNT();
275  CHECK_COPY(dest_index - src_pos);
276  for (i = 0; i < count; i++)
277  dest[dest_index + i] = dest[dest_index - src_pos + i];
278  dest_index += count;
279  }
280  }
281 
282  /* validate that the entire destination buffer was filled; this is
283  * important for decoding frame maps since each vector needs to have a
284  * codebook entry; it is not important for compressed codebooks because
285  * not every entry needs to be filled */
286  if (check_size)
287  if (dest_index < dest_size)
288  av_log(NULL, AV_LOG_ERROR, " VQA video: decode_format80 problem: decode finished with dest_index (%d) < dest_size (%d)\n",
289  dest_index, dest_size);
290 
291  return 0; // let's display what we decoded anyway
292 }
293 
295 {
296  unsigned int chunk_type;
297  unsigned int chunk_size;
298  int byte_skip;
299  unsigned int index = 0;
300  int i;
301  unsigned char r, g, b;
302  int index_shift;
303  int res;
304 
305  int cbf0_chunk = -1;
306  int cbfz_chunk = -1;
307  int cbp0_chunk = -1;
308  int cbpz_chunk = -1;
309  int cpl0_chunk = -1;
310  int cplz_chunk = -1;
311  int vptz_chunk = -1;
312 
313  int x, y;
314  int lines = 0;
315  int pixel_ptr;
316  int vector_index = 0;
317  int lobyte = 0;
318  int hibyte = 0;
319  int lobytes = 0;
320  int hibytes = s->decode_buffer_size / 2;
321 
322  /* first, traverse through the frame and find the subchunks */
323  while (bytestream2_get_bytes_left(&s->gb) >= 8) {
324 
325  chunk_type = bytestream2_get_be32u(&s->gb);
326  index = bytestream2_tell(&s->gb);
327  chunk_size = bytestream2_get_be32u(&s->gb);
328 
329  switch (chunk_type) {
330 
331  case CBF0_TAG:
332  cbf0_chunk = index;
333  break;
334 
335  case CBFZ_TAG:
336  cbfz_chunk = index;
337  break;
338 
339  case CBP0_TAG:
340  cbp0_chunk = index;
341  break;
342 
343  case CBPZ_TAG:
344  cbpz_chunk = index;
345  break;
346 
347  case CPL0_TAG:
348  cpl0_chunk = index;
349  break;
350 
351  case CPLZ_TAG:
352  cplz_chunk = index;
353  break;
354 
355  case VPTZ_TAG:
356  vptz_chunk = index;
357  break;
358 
359  default:
360  av_log(s->avctx, AV_LOG_ERROR, " VQA video: Found unknown chunk type: %c%c%c%c (%08X)\n",
361  (chunk_type >> 24) & 0xFF,
362  (chunk_type >> 16) & 0xFF,
363  (chunk_type >> 8) & 0xFF,
364  (chunk_type >> 0) & 0xFF,
365  chunk_type);
366  break;
367  }
368 
369  byte_skip = chunk_size & 0x01;
370  bytestream2_skip(&s->gb, chunk_size + byte_skip);
371  }
372 
373  /* next, deal with the palette */
374  if ((cpl0_chunk != -1) && (cplz_chunk != -1)) {
375 
376  /* a chunk should not have both chunk types */
377  av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: found both CPL0 and CPLZ chunks\n");
378  return AVERROR_INVALIDDATA;
379  }
380 
381  /* decompress the palette chunk */
382  if (cplz_chunk != -1) {
383 
384 /* yet to be handled */
385 
386  }
387 
388  /* convert the RGB palette into the machine's endian format */
389  if (cpl0_chunk != -1) {
390 
391  bytestream2_seek(&s->gb, cpl0_chunk, SEEK_SET);
392  chunk_size = bytestream2_get_be32(&s->gb);
393  /* sanity check the palette size */
394  if (chunk_size / 3 > 256 || chunk_size > bytestream2_get_bytes_left(&s->gb)) {
395  av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: found a palette chunk with %d colors\n",
396  chunk_size / 3);
397  return AVERROR_INVALIDDATA;
398  }
399  for (i = 0; i < chunk_size / 3; i++) {
400  /* scale by 4 to transform 6-bit palette -> 8-bit */
401  r = bytestream2_get_byteu(&s->gb) * 4;
402  g = bytestream2_get_byteu(&s->gb) * 4;
403  b = bytestream2_get_byteu(&s->gb) * 4;
404  s->palette[i] = (r << 16) | (g << 8) | (b);
405  }
406  }
407 
408  /* next, look for a full codebook */
409  if ((cbf0_chunk != -1) && (cbfz_chunk != -1)) {
410 
411  /* a chunk should not have both chunk types */
412  av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: found both CBF0 and CBFZ chunks\n");
413  return AVERROR_INVALIDDATA;
414  }
415 
416  /* decompress the full codebook chunk */
417  if (cbfz_chunk != -1) {
418 
419  bytestream2_seek(&s->gb, cbfz_chunk, SEEK_SET);
420  chunk_size = bytestream2_get_be32(&s->gb);
421  if ((res = decode_format80(&s->gb, chunk_size, s->codebook,
422  s->codebook_size, 0)) < 0)
423  return res;
424  }
425 
426  /* copy a full codebook */
427  if (cbf0_chunk != -1) {
428 
429  bytestream2_seek(&s->gb, cbf0_chunk, SEEK_SET);
430  chunk_size = bytestream2_get_be32(&s->gb);
431  /* sanity check the full codebook size */
432  if (chunk_size > MAX_CODEBOOK_SIZE) {
433  av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: CBF0 chunk too large (0x%X bytes)\n",
434  chunk_size);
435  return AVERROR_INVALIDDATA;
436  }
437 
438  bytestream2_get_buffer(&s->gb, s->codebook, chunk_size);
439  }
440 
441  /* decode the frame */
442  if (vptz_chunk == -1) {
443 
444  /* something is wrong if there is no VPTZ chunk */
445  av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: no VPTZ chunk found\n");
446  return AVERROR_INVALIDDATA;
447  }
448 
449  bytestream2_seek(&s->gb, vptz_chunk, SEEK_SET);
450  chunk_size = bytestream2_get_be32(&s->gb);
451  if ((res = decode_format80(&s->gb, chunk_size,
452  s->decode_buffer, s->decode_buffer_size, 1)) < 0)
453  return res;
454 
455  /* render the final PAL8 frame */
456  if (s->vector_height == 4)
457  index_shift = 4;
458  else
459  index_shift = 3;
460  for (y = 0; y < s->frame.linesize[0] * s->height;
461  y += s->frame.linesize[0] * s->vector_height) {
462 
463  for (x = y; x < y + s->width; x += 4, lobytes++, hibytes++) {
464  pixel_ptr = x;
465 
466  /* get the vector index, the method for which varies according to
467  * VQA file version */
468  switch (s->vqa_version) {
469 
470  case 1:
471  lobyte = s->decode_buffer[lobytes * 2];
472  hibyte = s->decode_buffer[(lobytes * 2) + 1];
473  vector_index = ((hibyte << 8) | lobyte) >> 3;
474  vector_index <<= index_shift;
475  lines = s->vector_height;
476  /* uniform color fill - a quick hack */
477  if (hibyte == 0xFF) {
478  while (lines--) {
479  s->frame.data[0][pixel_ptr + 0] = 255 - lobyte;
480  s->frame.data[0][pixel_ptr + 1] = 255 - lobyte;
481  s->frame.data[0][pixel_ptr + 2] = 255 - lobyte;
482  s->frame.data[0][pixel_ptr + 3] = 255 - lobyte;
483  pixel_ptr += s->frame.linesize[0];
484  }
485  lines=0;
486  }
487  break;
488 
489  case 2:
490  lobyte = s->decode_buffer[lobytes];
491  hibyte = s->decode_buffer[hibytes];
492  vector_index = (hibyte << 8) | lobyte;
493  vector_index <<= index_shift;
494  lines = s->vector_height;
495  break;
496 
497  case 3:
498 /* not implemented yet */
499  lines = 0;
500  break;
501  }
502 
503  while (lines--) {
504  s->frame.data[0][pixel_ptr + 0] = s->codebook[vector_index++];
505  s->frame.data[0][pixel_ptr + 1] = s->codebook[vector_index++];
506  s->frame.data[0][pixel_ptr + 2] = s->codebook[vector_index++];
507  s->frame.data[0][pixel_ptr + 3] = s->codebook[vector_index++];
508  pixel_ptr += s->frame.linesize[0];
509  }
510  }
511  }
512 
513  /* handle partial codebook */
514  if ((cbp0_chunk != -1) && (cbpz_chunk != -1)) {
515  /* a chunk should not have both chunk types */
516  av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: found both CBP0 and CBPZ chunks\n");
517  return AVERROR_INVALIDDATA;
518  }
519 
520  if (cbp0_chunk != -1) {
521 
522  bytestream2_seek(&s->gb, cbp0_chunk, SEEK_SET);
523  chunk_size = bytestream2_get_be32(&s->gb);
524 
525  /* accumulate partial codebook */
527  chunk_size);
528  s->next_codebook_buffer_index += chunk_size;
529 
530  s->partial_countdown--;
531  if (s->partial_countdown == 0) {
532 
533  /* time to replace codebook */
534  memcpy(s->codebook, s->next_codebook_buffer,
536 
537  /* reset accounting */
540  }
541  }
542 
543  if (cbpz_chunk != -1) {
544 
545  bytestream2_seek(&s->gb, cbpz_chunk, SEEK_SET);
546  chunk_size = bytestream2_get_be32(&s->gb);
547 
548  /* accumulate partial codebook */
550  chunk_size);
551  s->next_codebook_buffer_index += chunk_size;
552 
553  s->partial_countdown--;
554  if (s->partial_countdown == 0) {
555  GetByteContext gb;
556 
558  /* decompress codebook */
559  if ((res = decode_format80(&gb, s->next_codebook_buffer_index,
560  s->codebook, s->codebook_size, 0)) < 0)
561  return res;
562 
563  /* reset accounting */
566  }
567  }
568 
569  return 0;
570 }
571 
573  void *data, int *data_size,
574  AVPacket *avpkt)
575 {
576  VqaContext *s = avctx->priv_data;
577  int res;
578 
579  if (s->frame.data[0])
580  avctx->release_buffer(avctx, &s->frame);
581 
582  if (avctx->get_buffer(avctx, &s->frame)) {
583  av_log(s->avctx, AV_LOG_ERROR, " VQA Video: get_buffer() failed\n");
584  return -1;
585  }
586 
587  bytestream2_init(&s->gb, avpkt->data, avpkt->size);
588  if ((res = vqa_decode_chunk(s)) < 0)
589  return res;
590 
591  /* make the palette available on the way out */
592  memcpy(s->frame.data[1], s->palette, PALETTE_COUNT * 4);
593  s->frame.palette_has_changed = 1;
594 
595  *data_size = sizeof(AVFrame);
596  *(AVFrame*)data = s->frame;
597 
598  /* report that the buffer was completely consumed */
599  return avpkt->size;
600 }
601 
603 {
604  VqaContext *s = avctx->priv_data;
605 
606  av_free(s->codebook);
609 
610  if (s->frame.data[0])
611  avctx->release_buffer(avctx, &s->frame);
612 
613  return 0;
614 }
615 
617  .name = "vqavideo",
618  .type = AVMEDIA_TYPE_VIDEO,
619  .id = CODEC_ID_WS_VQA,
620  .priv_data_size = sizeof(VqaContext),
624  .capabilities = CODEC_CAP_DR1,
625  .long_name = NULL_IF_CONFIG_SMALL("Westwood Studios VQA (Vector Quantized Animation) video"),
626 };