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cinepak.c
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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  * @file
24  * Cinepak video decoder
25  * @author Ewald Snel <ewald@rambo.its.tudelft.nl>
26  *
27  * @see For more information on the Cinepak algorithm, visit:
28  * http://www.csse.monash.edu.au/~timf/
29  * @see 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  * Cinepak colorspace support (c) 2013 Rl, Aetey Global Technologies AB
33  * @author Cinepak colorspace, Rl, Aetey Global Technologies AB
34  */
35 
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 
40 #include "libavutil/common.h"
41 #include "libavutil/intreadwrite.h"
42 #include "avcodec.h"
43 
44 
45 typedef uint8_t cvid_codebook[12];
46 
47 #define MAX_STRIPS 32
48 
49 typedef struct {
50  uint16_t id;
51  uint16_t x1, y1;
52  uint16_t x2, y2;
53  cvid_codebook v4_codebook[256];
54  cvid_codebook v1_codebook[256];
55 } cvid_strip;
56 
57 typedef struct CinepakContext {
58 
61 
62  const unsigned char *data;
63  int size;
64 
65  int width, height;
66 
69 
71 
72  uint32_t pal[256];
74 
75 static void cinepak_decode_codebook (cvid_codebook *codebook,
76  int chunk_id, int size, const uint8_t *data)
77 {
78  const uint8_t *eod = (data + size);
79  uint32_t flag, mask;
80  int i, n;
81  uint8_t *p;
82 
83  /* check if this chunk contains 4- or 6-element vectors */
84  n = (chunk_id & 0x04) ? 4 : 6;
85  flag = 0;
86  mask = 0;
87 
88  p = codebook[0];
89  for (i=0; i < 256; i++) {
90  if ((chunk_id & 0x01) && !(mask >>= 1)) {
91  if ((data + 4) > eod)
92  break;
93 
94  flag = AV_RB32 (data);
95  data += 4;
96  mask = 0x80000000;
97  }
98 
99  if (!(chunk_id & 0x01) || (flag & mask)) {
100  int k, kk;
101 
102  if ((data + n) > eod)
103  break;
104 
105  for (k = 0; k < 4; ++k) {
106  int r = *data++;
107  for (kk = 0; kk < 3; ++kk)
108  *p++ = r;
109  }
110  if (n == 6) {
111  int r, g, b, u, v;
112  u = *(int8_t *)data++;
113  v = *(int8_t *)data++;
114  p -= 12;
115  for(k=0; k<4; ++k) {
116  r = *p++ + v*2;
117  g = *p++ - (u/2) - v;
118  b = *p + u*2;
119  p -= 2;
120  *p++ = av_clip_uint8(r);
121  *p++ = av_clip_uint8(g);
122  *p++ = av_clip_uint8(b);
123  }
124  }
125  } else {
126  p += 12;
127  }
128  }
129 }
130 
132  int chunk_id, int size, const uint8_t *data)
133 {
134  const uint8_t *eod = (data + size);
135  uint32_t flag, mask;
136  uint8_t *cb0, *cb1, *cb2, *cb3;
137  unsigned int x, y;
138  char *ip0, *ip1, *ip2, *ip3;
139 
140  flag = 0;
141  mask = 0;
142 
143  for (y=strip->y1; y < strip->y2; y+=4) {
144 
145 /* take care of y dimension not being multiple of 4, such streams exist */
146  ip0 = ip1 = ip2 = ip3 = s->frame.data[0] +
147  (s->palette_video?strip->x1:strip->x1*3) + (y * s->frame.linesize[0]);
148  if(s->avctx->height - y > 1) {
149  ip1 = ip0 + s->frame.linesize[0];
150  if(s->avctx->height - y > 2) {
151  ip2 = ip1 + s->frame.linesize[0];
152  if(s->avctx->height - y > 3) {
153  ip3 = ip2 + s->frame.linesize[0];
154  }
155  }
156  }
157 /* to get the correct picture for not-multiple-of-4 cases let us fill
158  * each block from the bottom up, thus possibly overwriting the top line
159  * more than once but ending with the correct data in place
160  * (instead of in-loop checking) */
161 
162  for (x=strip->x1; x < strip->x2; x+=4) {
163  if ((chunk_id & 0x01) && !(mask >>= 1)) {
164  if ((data + 4) > eod)
165  return AVERROR_INVALIDDATA;
166 
167  flag = AV_RB32 (data);
168  data += 4;
169  mask = 0x80000000;
170  }
171 
172  if (!(chunk_id & 0x01) || (flag & mask)) {
173  if (!(chunk_id & 0x02) && !(mask >>= 1)) {
174  if ((data + 4) > eod)
175  return AVERROR_INVALIDDATA;
176 
177  flag = AV_RB32 (data);
178  data += 4;
179  mask = 0x80000000;
180  }
181 
182  if ((chunk_id & 0x02) || (~flag & mask)) {
183  uint8_t *p;
184  if (data >= eod)
185  return AVERROR_INVALIDDATA;
186 
187  p = strip->v1_codebook[*data++];
188  if (s->palette_video) {
189  ip3[0] = ip3[1] = ip2[0] = ip2[1] = p[6];
190  ip3[2] = ip3[3] = ip2[2] = ip2[3] = p[9];
191  ip1[0] = ip1[1] = ip0[0] = ip0[1] = p[0];
192  ip1[2] = ip1[3] = ip0[2] = ip0[3] = p[3];
193  } else {
194  p += 6;
195  memcpy(ip3 + 0, p, 3); memcpy(ip3 + 3, p, 3);
196  memcpy(ip2 + 0, p, 3); memcpy(ip2 + 3, p, 3);
197  p += 3; /* ... + 9 */
198  memcpy(ip3 + 6, p, 3); memcpy(ip3 + 9, p, 3);
199  memcpy(ip2 + 6, p, 3); memcpy(ip2 + 9, p, 3);
200  p -= 9; /* ... + 0 */
201  memcpy(ip1 + 0, p, 3); memcpy(ip1 + 3, p, 3);
202  memcpy(ip0 + 0, p, 3); memcpy(ip0 + 3, p, 3);
203  p += 3; /* ... + 3 */
204  memcpy(ip1 + 6, p, 3); memcpy(ip1 + 9, p, 3);
205  memcpy(ip0 + 6, p, 3); memcpy(ip0 + 9, p, 3);
206  }
207 
208  } else if (flag & mask) {
209  if ((data + 4) > eod)
210  return AVERROR_INVALIDDATA;
211 
212  cb0 = strip->v4_codebook[*data++];
213  cb1 = strip->v4_codebook[*data++];
214  cb2 = strip->v4_codebook[*data++];
215  cb3 = strip->v4_codebook[*data++];
216  if (s->palette_video) {
217  uint8_t *p;
218  p = ip3;
219  *p++ = cb2[6];
220  *p++ = cb2[9];
221  *p++ = cb3[6];
222  *p = cb3[9];
223  p = ip2;
224  *p++ = cb2[0];
225  *p++ = cb2[3];
226  *p++ = cb3[0];
227  *p = cb3[3];
228  p = ip1;
229  *p++ = cb0[6];
230  *p++ = cb0[9];
231  *p++ = cb1[6];
232  *p = cb1[9];
233  p = ip0;
234  *p++ = cb0[0];
235  *p++ = cb0[3];
236  *p++ = cb1[0];
237  *p = cb1[3];
238  } else {
239  memcpy(ip3 + 0, cb2 + 6, 6);
240  memcpy(ip3 + 6, cb3 + 6, 6);
241  memcpy(ip2 + 0, cb2 + 0, 6);
242  memcpy(ip2 + 6, cb3 + 0, 6);
243  memcpy(ip1 + 0, cb0 + 6, 6);
244  memcpy(ip1 + 6, cb1 + 6, 6);
245  memcpy(ip0 + 0, cb0 + 0, 6);
246  memcpy(ip0 + 6, cb1 + 0, 6);
247  }
248 
249  }
250  }
251 
252  if (s->palette_video) {
253  ip0 += 4; ip1 += 4;
254  ip2 += 4; ip3 += 4;
255  } else {
256  ip0 += 12; ip1 += 12;
257  ip2 += 12; ip3 += 12;
258  }
259  }
260  }
261 
262  return 0;
263 }
264 
266  cvid_strip *strip, const uint8_t *data, int size)
267 {
268  const uint8_t *eod = (data + size);
269  int chunk_id, chunk_size;
270 
271  /* coordinate sanity checks */
272  if (strip->x2 > s->width ||
273  strip->y2 > s->height ||
274  strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
275  return AVERROR_INVALIDDATA;
276 
277  while ((data + 4) <= eod) {
278  chunk_id = data[0];
279  chunk_size = AV_RB24 (&data[1]) - 4;
280  if(chunk_size < 0)
281  return AVERROR_INVALIDDATA;
282 
283  data += 4;
284  chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
285 
286  switch (chunk_id) {
287 
288  case 0x20:
289  case 0x21:
290  case 0x24:
291  case 0x25:
292  cinepak_decode_codebook (strip->v4_codebook, chunk_id,
293  chunk_size, data);
294  break;
295 
296  case 0x22:
297  case 0x23:
298  case 0x26:
299  case 0x27:
300  cinepak_decode_codebook (strip->v1_codebook, chunk_id,
301  chunk_size, data);
302  break;
303 
304  case 0x30:
305  case 0x31:
306  case 0x32:
307  return cinepak_decode_vectors (s, strip, chunk_id,
308  chunk_size, data);
309  }
310 
311  data += chunk_size;
312  }
313 
314  return AVERROR_INVALIDDATA;
315 }
316 
318 {
319  const uint8_t *eod = (s->data + s->size);
320  int i, result, strip_size, frame_flags, num_strips;
321  int y0 = 0;
322  int encoded_buf_size;
323 
324  if (s->size < 10)
325  return AVERROR_INVALIDDATA;
326 
327  frame_flags = s->data[0];
328  num_strips = AV_RB16 (&s->data[8]);
329  encoded_buf_size = AV_RB24(&s->data[1]);
330 
331  /* if this is the first frame, check for deviant Sega FILM data */
332  if (s->sega_film_skip_bytes == -1) {
333  if (!encoded_buf_size) {
334  av_log_ask_for_sample(s->avctx, "encoded_buf_size is 0");
335  return AVERROR_PATCHWELCOME;
336  }
337  if (encoded_buf_size != s->size && (s->size % encoded_buf_size) != 0) {
338  /* If the encoded frame size differs from the frame size as indicated
339  * by the container file, this data likely comes from a Sega FILM/CPK file.
340  * If the frame header is followed by the bytes FE 00 00 06 00 00 then
341  * this is probably one of the two known files that have 6 extra bytes
342  * after the frame header. Else, assume 2 extra bytes. The container
343  * size also cannot be a multiple of the encoded size. */
344  if (s->size >= 16 &&
345  (s->data[10] == 0xFE) &&
346  (s->data[11] == 0x00) &&
347  (s->data[12] == 0x00) &&
348  (s->data[13] == 0x06) &&
349  (s->data[14] == 0x00) &&
350  (s->data[15] == 0x00))
351  s->sega_film_skip_bytes = 6;
352  else
353  s->sega_film_skip_bytes = 2;
354  } else
355  s->sega_film_skip_bytes = 0;
356  }
357 
358  s->data += 10 + s->sega_film_skip_bytes;
359 
360  num_strips = FFMIN(num_strips, MAX_STRIPS);
361 
362  s->frame.key_frame = 0;
363 
364  for (i=0; i < num_strips; i++) {
365  if ((s->data + 12) > eod)
366  return AVERROR_INVALIDDATA;
367 
368  s->strips[i].id = s->data[0];
369 /* zero y1 means "relative to the previous stripe" */
370  if (!(s->strips[i].y1 = AV_RB16 (&s->data[4])))
371  s->strips[i].y2 = (s->strips[i].y1 = y0) + AV_RB16 (&s->data[8]);
372  else
373  s->strips[i].y2 = AV_RB16 (&s->data[8]);
374  s->strips[i].x1 = AV_RB16 (&s->data[6]);
375  s->strips[i].x2 = AV_RB16 (&s->data[10]);
376 
377  if (s->strips[i].id == 0x10)
378  s->frame.key_frame = 1;
379 
380  strip_size = AV_RB24 (&s->data[1]) - 12;
381  if (strip_size < 0)
382  return AVERROR_INVALIDDATA;
383  s->data += 12;
384  strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
385 
386  if ((i > 0) && !(frame_flags & 0x01)) {
387  memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
388  sizeof(s->strips[i].v4_codebook));
389  memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
390  sizeof(s->strips[i].v1_codebook));
391  }
392 
393  result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
394 
395  if (result != 0)
396  return result;
397 
398  s->data += strip_size;
399  y0 = s->strips[i].y2;
400  }
401  return 0;
402 }
403 
405 {
406  CinepakContext *s = avctx->priv_data;
407 
408  s->avctx = avctx;
409  s->width = (avctx->width + 3) & ~3;
410  s->height = (avctx->height + 3) & ~3;
411 
412  s->sega_film_skip_bytes = -1; /* uninitialized state */
413 
414  // check for paletted data
415  if (avctx->bits_per_coded_sample != 8) {
416  s->palette_video = 0;
417  avctx->pix_fmt = AV_PIX_FMT_RGB24;
418  } else {
419  s->palette_video = 1;
420  avctx->pix_fmt = AV_PIX_FMT_PAL8;
421  }
422 
424  s->frame.data[0] = NULL;
425 
426  return 0;
427 }
428 
430  void *data, int *got_frame,
431  AVPacket *avpkt)
432 {
433  const uint8_t *buf = avpkt->data;
434  int ret = 0, buf_size = avpkt->size;
435  CinepakContext *s = avctx->priv_data;
436 
437  s->data = buf;
438  s->size = buf_size;
439 
440  s->frame.reference = 3;
443  if ((ret = avctx->reget_buffer(avctx, &s->frame))) {
444  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
445  return ret;
446  }
447 
448  if (s->palette_video) {
450  if (pal) {
451  s->frame.palette_has_changed = 1;
452  memcpy(s->pal, pal, AVPALETTE_SIZE);
453  }
454  }
455 
456  if ((ret = cinepak_decode(s)) < 0) {
457  av_log(avctx, AV_LOG_ERROR, "cinepak_decode failed\n");
458  }
459 
460  if (s->palette_video)
461  memcpy (s->frame.data[1], s->pal, AVPALETTE_SIZE);
462 
463  *got_frame = 1;
464  *(AVFrame*)data = s->frame;
465 
466  /* report that the buffer was completely consumed */
467  return buf_size;
468 }
469 
471 {
472  CinepakContext *s = avctx->priv_data;
473 
474  if (s->frame.data[0])
475  avctx->release_buffer(avctx, &s->frame);
476 
477  return 0;
478 }
479 
481  .name = "cinepak",
482  .type = AVMEDIA_TYPE_VIDEO,
483  .id = AV_CODEC_ID_CINEPAK,
484  .priv_data_size = sizeof(CinepakContext),
488  .capabilities = CODEC_CAP_DR1,
489  .long_name = NULL_IF_CONFIG_SMALL("Cinepak"),
490 };