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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 #include "internal.h"
44 
45 
46 typedef uint8_t cvid_codebook[12];
47 
48 #define MAX_STRIPS 32
49 
50 typedef struct cvid_strip {
51  uint16_t id;
52  uint16_t x1, y1;
53  uint16_t x2, y2;
56 } cvid_strip;
57 
58 typedef struct CinepakContext {
59 
62 
63  const unsigned char *data;
64  int size;
65 
66  int width, height;
67 
70 
72 
73  uint32_t pal[256];
75 
76 static void cinepak_decode_codebook (cvid_codebook *codebook,
77  int chunk_id, int size, const uint8_t *data)
78 {
79  const uint8_t *eod = (data + size);
80  uint32_t flag, mask;
81  int i, n;
82  uint8_t *p;
83 
84  /* check if this chunk contains 4- or 6-element vectors */
85  n = (chunk_id & 0x04) ? 4 : 6;
86  flag = 0;
87  mask = 0;
88 
89  p = codebook[0];
90  for (i=0; i < 256; i++) {
91  if ((chunk_id & 0x01) && !(mask >>= 1)) {
92  if ((data + 4) > eod)
93  break;
94 
95  flag = AV_RB32 (data);
96  data += 4;
97  mask = 0x80000000;
98  }
99 
100  if (!(chunk_id & 0x01) || (flag & mask)) {
101  int k, kk;
102 
103  if ((data + n) > eod)
104  break;
105 
106  for (k = 0; k < 4; ++k) {
107  int r = *data++;
108  for (kk = 0; kk < 3; ++kk)
109  *p++ = r;
110  }
111  if (n == 6) {
112  int r, g, b, u, v;
113  u = *(int8_t *)data++;
114  v = *(int8_t *)data++;
115  p -= 12;
116  for(k=0; k<4; ++k) {
117  r = *p++ + v*2;
118  g = *p++ - (u/2) - v;
119  b = *p + u*2;
120  p -= 2;
121  *p++ = av_clip_uint8(r);
122  *p++ = av_clip_uint8(g);
123  *p++ = av_clip_uint8(b);
124  }
125  }
126  } else {
127  p += 12;
128  }
129  }
130 }
131 
133  int chunk_id, int size, const uint8_t *data)
134 {
135  const uint8_t *eod = (data + size);
136  uint32_t flag, mask;
137  uint8_t *cb0, *cb1, *cb2, *cb3;
138  int x, y;
139  char *ip0, *ip1, *ip2, *ip3;
140 
141  flag = 0;
142  mask = 0;
143 
144  for (y=strip->y1; y < strip->y2; y+=4) {
145 
146 /* take care of y dimension not being multiple of 4, such streams exist */
147  ip0 = ip1 = ip2 = ip3 = s->frame->data[0] +
148  (s->palette_video?strip->x1:strip->x1*3) + (y * s->frame->linesize[0]);
149  if(s->avctx->height - y > 1) {
150  ip1 = ip0 + s->frame->linesize[0];
151  if(s->avctx->height - y > 2) {
152  ip2 = ip1 + s->frame->linesize[0];
153  if(s->avctx->height - y > 3) {
154  ip3 = ip2 + s->frame->linesize[0];
155  }
156  }
157  }
158 /* to get the correct picture for not-multiple-of-4 cases let us fill
159  * each block from the bottom up, thus possibly overwriting the top line
160  * more than once but ending with the correct data in place
161  * (instead of in-loop checking) */
162 
163  for (x=strip->x1; x < strip->x2; x+=4) {
164  if ((chunk_id & 0x01) && !(mask >>= 1)) {
165  if ((data + 4) > eod)
166  return AVERROR_INVALIDDATA;
167 
168  flag = AV_RB32 (data);
169  data += 4;
170  mask = 0x80000000;
171  }
172 
173  if (!(chunk_id & 0x01) || (flag & mask)) {
174  if (!(chunk_id & 0x02) && !(mask >>= 1)) {
175  if ((data + 4) > eod)
176  return AVERROR_INVALIDDATA;
177 
178  flag = AV_RB32 (data);
179  data += 4;
180  mask = 0x80000000;
181  }
182 
183  if ((chunk_id & 0x02) || (~flag & mask)) {
184  uint8_t *p;
185  if (data >= eod)
186  return AVERROR_INVALIDDATA;
187 
188  p = strip->v1_codebook[*data++];
189  if (s->palette_video) {
190  ip3[0] = ip3[1] = ip2[0] = ip2[1] = p[6];
191  ip3[2] = ip3[3] = ip2[2] = ip2[3] = p[9];
192  ip1[0] = ip1[1] = ip0[0] = ip0[1] = p[0];
193  ip1[2] = ip1[3] = ip0[2] = ip0[3] = p[3];
194  } else {
195  p += 6;
196  memcpy(ip3 + 0, p, 3); memcpy(ip3 + 3, p, 3);
197  memcpy(ip2 + 0, p, 3); memcpy(ip2 + 3, p, 3);
198  p += 3; /* ... + 9 */
199  memcpy(ip3 + 6, p, 3); memcpy(ip3 + 9, p, 3);
200  memcpy(ip2 + 6, p, 3); memcpy(ip2 + 9, p, 3);
201  p -= 9; /* ... + 0 */
202  memcpy(ip1 + 0, p, 3); memcpy(ip1 + 3, p, 3);
203  memcpy(ip0 + 0, p, 3); memcpy(ip0 + 3, p, 3);
204  p += 3; /* ... + 3 */
205  memcpy(ip1 + 6, p, 3); memcpy(ip1 + 9, p, 3);
206  memcpy(ip0 + 6, p, 3); memcpy(ip0 + 9, p, 3);
207  }
208 
209  } else if (flag & mask) {
210  if ((data + 4) > eod)
211  return AVERROR_INVALIDDATA;
212 
213  cb0 = strip->v4_codebook[*data++];
214  cb1 = strip->v4_codebook[*data++];
215  cb2 = strip->v4_codebook[*data++];
216  cb3 = strip->v4_codebook[*data++];
217  if (s->palette_video) {
218  uint8_t *p;
219  p = ip3;
220  *p++ = cb2[6];
221  *p++ = cb2[9];
222  *p++ = cb3[6];
223  *p = cb3[9];
224  p = ip2;
225  *p++ = cb2[0];
226  *p++ = cb2[3];
227  *p++ = cb3[0];
228  *p = cb3[3];
229  p = ip1;
230  *p++ = cb0[6];
231  *p++ = cb0[9];
232  *p++ = cb1[6];
233  *p = cb1[9];
234  p = ip0;
235  *p++ = cb0[0];
236  *p++ = cb0[3];
237  *p++ = cb1[0];
238  *p = cb1[3];
239  } else {
240  memcpy(ip3 + 0, cb2 + 6, 6);
241  memcpy(ip3 + 6, cb3 + 6, 6);
242  memcpy(ip2 + 0, cb2 + 0, 6);
243  memcpy(ip2 + 6, cb3 + 0, 6);
244  memcpy(ip1 + 0, cb0 + 6, 6);
245  memcpy(ip1 + 6, cb1 + 6, 6);
246  memcpy(ip0 + 0, cb0 + 0, 6);
247  memcpy(ip0 + 6, cb1 + 0, 6);
248  }
249 
250  }
251  }
252 
253  if (s->palette_video) {
254  ip0 += 4; ip1 += 4;
255  ip2 += 4; ip3 += 4;
256  } else {
257  ip0 += 12; ip1 += 12;
258  ip2 += 12; ip3 += 12;
259  }
260  }
261  }
262 
263  return 0;
264 }
265 
267  cvid_strip *strip, const uint8_t *data, int size)
268 {
269  const uint8_t *eod = (data + size);
270  int chunk_id, chunk_size;
271 
272  /* coordinate sanity checks */
273  if (strip->x2 > s->width ||
274  strip->y2 > s->height ||
275  strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
276  return AVERROR_INVALIDDATA;
277 
278  while ((data + 4) <= eod) {
279  chunk_id = data[0];
280  chunk_size = AV_RB24 (&data[1]) - 4;
281  if(chunk_size < 0)
282  return AVERROR_INVALIDDATA;
283 
284  data += 4;
285  chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
286 
287  switch (chunk_id) {
288 
289  case 0x20:
290  case 0x21:
291  case 0x24:
292  case 0x25:
293  cinepak_decode_codebook (strip->v4_codebook, chunk_id,
294  chunk_size, data);
295  break;
296 
297  case 0x22:
298  case 0x23:
299  case 0x26:
300  case 0x27:
301  cinepak_decode_codebook (strip->v1_codebook, chunk_id,
302  chunk_size, data);
303  break;
304 
305  case 0x30:
306  case 0x31:
307  case 0x32:
308  return cinepak_decode_vectors (s, strip, chunk_id,
309  chunk_size, data);
310  }
311 
312  data += chunk_size;
313  }
314 
315  return AVERROR_INVALIDDATA;
316 }
317 
319 {
320  const uint8_t *eod = (s->data + s->size);
321  int i, result, strip_size, frame_flags, num_strips;
322  int y0 = 0;
323  int encoded_buf_size;
324 
325  if (s->size < 10)
326  return AVERROR_INVALIDDATA;
327 
328  frame_flags = s->data[0];
329  num_strips = AV_RB16 (&s->data[8]);
330  encoded_buf_size = AV_RB24(&s->data[1]);
331 
332  /* if this is the first frame, check for deviant Sega FILM data */
333  if (s->sega_film_skip_bytes == -1) {
334  if (!encoded_buf_size) {
335  avpriv_request_sample(s->avctx, "encoded_buf_size 0");
336  return AVERROR_PATCHWELCOME;
337  }
338  if (encoded_buf_size != s->size && (s->size % encoded_buf_size) != 0) {
339  /* If the encoded frame size differs from the frame size as indicated
340  * by the container file, this data likely comes from a Sega FILM/CPK file.
341  * If the frame header is followed by the bytes FE 00 00 06 00 00 then
342  * this is probably one of the two known files that have 6 extra bytes
343  * after the frame header. Else, assume 2 extra bytes. The container
344  * size also cannot be a multiple of the encoded size. */
345  if (s->size >= 16 &&
346  (s->data[10] == 0xFE) &&
347  (s->data[11] == 0x00) &&
348  (s->data[12] == 0x00) &&
349  (s->data[13] == 0x06) &&
350  (s->data[14] == 0x00) &&
351  (s->data[15] == 0x00))
352  s->sega_film_skip_bytes = 6;
353  else
354  s->sega_film_skip_bytes = 2;
355  } else
356  s->sega_film_skip_bytes = 0;
357  }
358 
359  s->data += 10 + s->sega_film_skip_bytes;
360 
361  num_strips = FFMIN(num_strips, MAX_STRIPS);
362 
363  s->frame->key_frame = 0;
364 
365  for (i=0; i < num_strips; i++) {
366  if ((s->data + 12) > eod)
367  return AVERROR_INVALIDDATA;
368 
369  s->strips[i].id = s->data[0];
370 /* zero y1 means "relative to the previous stripe" */
371  if (!(s->strips[i].y1 = AV_RB16 (&s->data[4])))
372  s->strips[i].y2 = (s->strips[i].y1 = y0) + AV_RB16 (&s->data[8]);
373  else
374  s->strips[i].y2 = AV_RB16 (&s->data[8]);
375  s->strips[i].x1 = AV_RB16 (&s->data[6]);
376  s->strips[i].x2 = AV_RB16 (&s->data[10]);
377 
378  if (s->strips[i].id == 0x10)
379  s->frame->key_frame = 1;
380 
381  strip_size = AV_RB24 (&s->data[1]) - 12;
382  if (strip_size < 0)
383  return AVERROR_INVALIDDATA;
384  s->data += 12;
385  strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
386 
387  if ((i > 0) && !(frame_flags & 0x01)) {
388  memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
389  sizeof(s->strips[i].v4_codebook));
390  memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
391  sizeof(s->strips[i].v1_codebook));
392  }
393 
394  result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
395 
396  if (result != 0)
397  return result;
398 
399  s->data += strip_size;
400  y0 = s->strips[i].y2;
401  }
402  return 0;
403 }
404 
406 {
407  CinepakContext *s = avctx->priv_data;
408 
409  s->avctx = avctx;
410  s->width = (avctx->width + 3) & ~3;
411  s->height = (avctx->height + 3) & ~3;
412 
413  s->sega_film_skip_bytes = -1; /* uninitialized state */
414 
415  // check for paletted data
416  if (avctx->bits_per_coded_sample != 8) {
417  s->palette_video = 0;
418  avctx->pix_fmt = AV_PIX_FMT_RGB24;
419  } else {
420  s->palette_video = 1;
421  avctx->pix_fmt = AV_PIX_FMT_PAL8;
422  }
423 
424  s->frame = av_frame_alloc();
425  if (!s->frame)
426  return AVERROR(ENOMEM);
427 
428  return 0;
429 }
430 
432  void *data, int *got_frame,
433  AVPacket *avpkt)
434 {
435  const uint8_t *buf = avpkt->data;
436  int ret = 0, buf_size = avpkt->size;
437  CinepakContext *s = avctx->priv_data;
438 
439  s->data = buf;
440  s->size = buf_size;
441 
442  if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
443  return ret;
444 
445  if (s->palette_video) {
447  if (pal) {
448  s->frame->palette_has_changed = 1;
449  memcpy(s->pal, pal, AVPALETTE_SIZE);
450  }
451  }
452 
453  if ((ret = cinepak_decode(s)) < 0) {
454  av_log(avctx, AV_LOG_ERROR, "cinepak_decode failed\n");
455  }
456 
457  if (s->palette_video)
458  memcpy (s->frame->data[1], s->pal, AVPALETTE_SIZE);
459 
460  if ((ret = av_frame_ref(data, s->frame)) < 0)
461  return ret;
462 
463  *got_frame = 1;
464 
465  /* report that the buffer was completely consumed */
466  return buf_size;
467 }
468 
470 {
471  CinepakContext *s = avctx->priv_data;
472 
473  av_frame_free(&s->frame);
474 
475  return 0;
476 }
477 
479  .name = "cinepak",
480  .long_name = NULL_IF_CONFIG_SMALL("Cinepak"),
481  .type = AVMEDIA_TYPE_VIDEO,
482  .id = AV_CODEC_ID_CINEPAK,
483  .priv_data_size = sizeof(CinepakContext),
485  .close = cinepak_decode_end,
487  .capabilities = CODEC_CAP_DR1,
488 };