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ffv1dec.c
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1 /*
2  * FFV1 decoder
3  *
4  * Copyright (c) 2003-2012 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * FF Video Codec 1 (a lossless codec) decoder
26  */
27 
28 #include "libavutil/avassert.h"
29 #include "libavutil/crc.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/imgutils.h"
32 #include "libavutil/pixdesc.h"
33 #include "libavutil/timer.h"
34 #include "avcodec.h"
35 #include "internal.h"
36 #include "get_bits.h"
37 #include "put_bits.h"
38 #include "dsputil.h"
39 #include "rangecoder.h"
40 #include "golomb.h"
41 #include "mathops.h"
42 #include "ffv1.h"
43 
45  int is_signed)
46 {
47  if (get_rac(c, state + 0))
48  return 0;
49  else {
50  int i, e, a;
51  e = 0;
52  while (get_rac(c, state + 1 + FFMIN(e, 9))) // 1..10
53  e++;
54 
55  a = 1;
56  for (i = e - 1; i >= 0; i--)
57  a += a + get_rac(c, state + 22 + FFMIN(i, 9)); // 22..31
58 
59  e = -(is_signed && get_rac(c, state + 11 + FFMIN(e, 10))); // 11..21
60  return (a ^ e) - e;
61  }
62 }
63 
64 static av_noinline int get_symbol(RangeCoder *c, uint8_t *state, int is_signed)
65 {
66  return get_symbol_inline(c, state, is_signed);
67 }
68 
69 static inline int get_vlc_symbol(GetBitContext *gb, VlcState *const state,
70  int bits)
71 {
72  int k, i, v, ret;
73 
74  i = state->count;
75  k = 0;
76  while (i < state->error_sum) { // FIXME: optimize
77  k++;
78  i += i;
79  }
80 
81  v = get_sr_golomb(gb, k, 12, bits);
82  av_dlog(NULL, "v:%d bias:%d error:%d drift:%d count:%d k:%d",
83  v, state->bias, state->error_sum, state->drift, state->count, k);
84 
85 #if 0 // JPEG LS
86  if (k == 0 && 2 * state->drift <= -state->count)
87  v ^= (-1);
88 #else
89  v ^= ((2 * state->drift + state->count) >> 31);
90 #endif
91 
92  ret = fold(v + state->bias, bits);
93 
94  update_vlc_state(state, v);
95 
96  return ret;
97 }
98 
100  int16_t *sample[2],
101  int plane_index, int bits)
102 {
103  PlaneContext *const p = &s->plane[plane_index];
104  RangeCoder *const c = &s->c;
105  int x;
106  int run_count = 0;
107  int run_mode = 0;
108  int run_index = s->run_index;
109 
110  for (x = 0; x < w; x++) {
111  int diff, context, sign;
112 
113  context = get_context(p, sample[1] + x, sample[0] + x, sample[1] + x);
114  if (context < 0) {
115  context = -context;
116  sign = 1;
117  } else
118  sign = 0;
119 
120  av_assert2(context < p->context_count);
121 
122  if (s->ac) {
123  diff = get_symbol_inline(c, p->state[context], 1);
124  } else {
125  if (context == 0 && run_mode == 0)
126  run_mode = 1;
127 
128  if (run_mode) {
129  if (run_count == 0 && run_mode == 1) {
130  if (get_bits1(&s->gb)) {
131  run_count = 1 << ff_log2_run[run_index];
132  if (x + run_count <= w)
133  run_index++;
134  } else {
135  if (ff_log2_run[run_index])
136  run_count = get_bits(&s->gb, ff_log2_run[run_index]);
137  else
138  run_count = 0;
139  if (run_index)
140  run_index--;
141  run_mode = 2;
142  }
143  }
144  run_count--;
145  if (run_count < 0) {
146  run_mode = 0;
147  run_count = 0;
148  diff = get_vlc_symbol(&s->gb, &p->vlc_state[context],
149  bits);
150  if (diff >= 0)
151  diff++;
152  } else
153  diff = 0;
154  } else
155  diff = get_vlc_symbol(&s->gb, &p->vlc_state[context], bits);
156 
157  av_dlog(s->avctx, "count:%d index:%d, mode:%d, x:%d pos:%d\n",
158  run_count, run_index, run_mode, x, get_bits_count(&s->gb));
159  }
160 
161  if (sign)
162  diff = -diff;
163 
164  sample[1][x] = (predict(sample[1] + x, sample[0] + x) + diff) &
165  ((1 << bits) - 1);
166  }
167  s->run_index = run_index;
168 }
169 
170 static void decode_plane(FFV1Context *s, uint8_t *src,
171  int w, int h, int stride, int plane_index)
172 {
173  int x, y;
174  int16_t *sample[2];
175  sample[0] = s->sample_buffer + 3;
176  sample[1] = s->sample_buffer + w + 6 + 3;
177 
178  s->run_index = 0;
179 
180  memset(s->sample_buffer, 0, 2 * (w + 6) * sizeof(*s->sample_buffer));
181 
182  for (y = 0; y < h; y++) {
183  int16_t *temp = sample[0]; // FIXME: try a normal buffer
184 
185  sample[0] = sample[1];
186  sample[1] = temp;
187 
188  sample[1][-1] = sample[0][0];
189  sample[0][w] = sample[0][w - 1];
190 
191 // { START_TIMER
192  if (s->avctx->bits_per_raw_sample <= 8) {
193  decode_line(s, w, sample, plane_index, 8);
194  for (x = 0; x < w; x++)
195  src[x + stride * y] = sample[1][x];
196  } else {
197  decode_line(s, w, sample, plane_index, s->avctx->bits_per_raw_sample);
198  if (s->packed_at_lsb) {
199  for (x = 0; x < w; x++) {
200  ((uint16_t*)(src + stride*y))[x] = sample[1][x];
201  }
202  } else {
203  for (x = 0; x < w; x++) {
204  ((uint16_t*)(src + stride*y))[x] = sample[1][x] << (16 - s->avctx->bits_per_raw_sample);
205  }
206  }
207  }
208 // STOP_TIMER("decode-line") }
209  }
210 }
211 
212 static void decode_rgb_frame(FFV1Context *s, uint8_t *src[3], int w, int h, int stride[3])
213 {
214  int x, y, p;
215  int16_t *sample[4][2];
216  int lbd = s->avctx->bits_per_raw_sample <= 8;
217  int bits = s->avctx->bits_per_raw_sample > 0 ? s->avctx->bits_per_raw_sample : 8;
218  int offset = 1 << bits;
219 
220  for (x = 0; x < 4; x++) {
221  sample[x][0] = s->sample_buffer + x * 2 * (w + 6) + 3;
222  sample[x][1] = s->sample_buffer + (x * 2 + 1) * (w + 6) + 3;
223  }
224 
225  s->run_index = 0;
226 
227  memset(s->sample_buffer, 0, 8 * (w + 6) * sizeof(*s->sample_buffer));
228 
229  for (y = 0; y < h; y++) {
230  for (p = 0; p < 3 + s->transparency; p++) {
231  int16_t *temp = sample[p][0]; // FIXME: try a normal buffer
232 
233  sample[p][0] = sample[p][1];
234  sample[p][1] = temp;
235 
236  sample[p][1][-1]= sample[p][0][0 ];
237  sample[p][0][ w]= sample[p][0][w-1];
238  if (lbd)
239  decode_line(s, w, sample[p], (p + 1)/2, 9);
240  else
241  decode_line(s, w, sample[p], (p + 1)/2, bits + 1);
242  }
243  for (x = 0; x < w; x++) {
244  int g = sample[0][1][x];
245  int b = sample[1][1][x];
246  int r = sample[2][1][x];
247  int a = sample[3][1][x];
248 
249  b -= offset;
250  r -= offset;
251  g -= (b + r) >> 2;
252  b += g;
253  r += g;
254 
255  if (lbd)
256  *((uint32_t*)(src[0] + x*4 + stride[0]*y)) = b + (g<<8) + (r<<16) + (a<<24);
257  else {
258  *((uint16_t*)(src[0] + x*2 + stride[0]*y)) = b;
259  *((uint16_t*)(src[1] + x*2 + stride[1]*y)) = g;
260  *((uint16_t*)(src[2] + x*2 + stride[2]*y)) = r;
261  }
262  }
263  }
264 }
265 
267 {
268  RangeCoder *c = &fs->c;
270  unsigned ps, i, context_count;
271  memset(state, 128, sizeof(state));
272 
273  av_assert0(f->version > 2);
274 
275  fs->slice_x = get_symbol(c, state, 0) * f->width ;
276  fs->slice_y = get_symbol(c, state, 0) * f->height;
277  fs->slice_width = (get_symbol(c, state, 0) + 1) * f->width + fs->slice_x;
278  fs->slice_height = (get_symbol(c, state, 0) + 1) * f->height + fs->slice_y;
279 
280  fs->slice_x /= f->num_h_slices;
281  fs->slice_y /= f->num_v_slices;
282  fs->slice_width = fs->slice_width /f->num_h_slices - fs->slice_x;
283  fs->slice_height = fs->slice_height/f->num_v_slices - fs->slice_y;
284  if ((unsigned)fs->slice_width > f->width || (unsigned)fs->slice_height > f->height)
285  return -1;
286  if ( (unsigned)fs->slice_x + (uint64_t)fs->slice_width > f->width
287  || (unsigned)fs->slice_y + (uint64_t)fs->slice_height > f->height)
288  return -1;
289 
290  for (i = 0; i < f->plane_count; i++) {
291  PlaneContext * const p = &fs->plane[i];
292  int idx = get_symbol(c, state, 0);
293  if (idx > (unsigned)f->quant_table_count) {
294  av_log(f->avctx, AV_LOG_ERROR, "quant_table_index out of range\n");
295  return -1;
296  }
297  p->quant_table_index = idx;
298  memcpy(p->quant_table, f->quant_tables[idx], sizeof(p->quant_table));
299  context_count = f->context_count[idx];
300 
301  if (p->context_count < context_count) {
302  av_freep(&p->state);
303  av_freep(&p->vlc_state);
304  }
306  }
307 
308  ps = get_symbol(c, state, 0);
309  if (ps == 1) {
310  f->picture.interlaced_frame = 1;
311  f->picture.top_field_first = 1;
312  } else if (ps == 2) {
313  f->picture.interlaced_frame = 1;
314  f->picture.top_field_first = 0;
315  } else if (ps == 3) {
316  f->picture.interlaced_frame = 0;
317  }
318  f->picture.sample_aspect_ratio.num = get_symbol(c, state, 0);
319  f->picture.sample_aspect_ratio.den = get_symbol(c, state, 0);
320 
321  return 0;
322 }
323 
324 static int decode_slice(AVCodecContext *c, void *arg)
325 {
326  FFV1Context *fs = *(void **)arg;
327  FFV1Context *f = fs->avctx->priv_data;
328  int width, height, x, y, ret;
329  const int ps = av_pix_fmt_desc_get(c->pix_fmt)->comp[0].step_minus1 + 1;
330  AVFrame * const p = &f->picture;
331 
332  if (f->version > 2) {
333  if (ffv1_init_slice_state(f, fs) < 0)
334  return AVERROR(ENOMEM);
335  if (decode_slice_header(f, fs) < 0) {
336  fs->slice_damaged = 1;
337  return AVERROR_INVALIDDATA;
338  }
339  }
340  if ((ret = ffv1_init_slice_state(f, fs)) < 0)
341  return ret;
342  if (f->picture.key_frame)
343  ffv1_clear_slice_state(f, fs);
344 
345  width = fs->slice_width;
346  height = fs->slice_height;
347  x = fs->slice_x;
348  y = fs->slice_y;
349 
350  if (!fs->ac) {
351  if (f->version == 3 && f->minor_version > 1 || f->version > 3)
352  get_rac(&fs->c, (uint8_t[]) { 129 });
353  fs->ac_byte_count = f->version > 2 || (!x && !y) ? fs->c.bytestream - fs->c.bytestream_start - 1 : 0;
354  init_get_bits(&fs->gb,
355  fs->c.bytestream_start + fs->ac_byte_count,
356  (fs->c.bytestream_end - fs->c.bytestream_start - fs->ac_byte_count) * 8);
357  }
358 
359  av_assert1(width && height);
360  if (f->colorspace == 0) {
361  const int chroma_width = -((-width) >> f->chroma_h_shift);
362  const int chroma_height = -((-height) >> f->chroma_v_shift);
363  const int cx = x >> f->chroma_h_shift;
364  const int cy = y >> f->chroma_v_shift;
365  decode_plane(fs, p->data[0] + ps*x + y*p->linesize[0], width, height, p->linesize[0], 0);
366 
367  if (f->chroma_planes) {
368  decode_plane(fs, p->data[1] + ps*cx+cy*p->linesize[1], chroma_width, chroma_height, p->linesize[1], 1);
369  decode_plane(fs, p->data[2] + ps*cx+cy*p->linesize[2], chroma_width, chroma_height, p->linesize[2], 1);
370  }
371  if (fs->transparency)
372  decode_plane(fs, p->data[3] + ps*x + y*p->linesize[3], width, height, p->linesize[3], 2);
373  } else {
374  uint8_t *planes[3] = { p->data[0] + ps * x + y * p->linesize[0],
375  p->data[1] + ps * x + y * p->linesize[1],
376  p->data[2] + ps * x + y * p->linesize[2] };
377  decode_rgb_frame(fs, planes, width, height, p->linesize);
378  }
379  if (fs->ac && f->version > 2) {
380  int v;
381  get_rac(&fs->c, (uint8_t[]) { 129 });
382  v = fs->c.bytestream_end - fs->c.bytestream - 2 - 5*f->ec;
383  if (v) {
384  av_log(f->avctx, AV_LOG_ERROR, "bytestream end mismatching by %d\n", v);
385  fs->slice_damaged = 1;
386  }
387  }
388 
389  emms_c();
390 
391  return 0;
392 }
393 
394 static int read_quant_table(RangeCoder *c, int16_t *quant_table, int scale)
395 {
396  int v;
397  int i = 0;
399 
400  memset(state, 128, sizeof(state));
401 
402  for (v = 0; i < 128; v++) {
403  unsigned len = get_symbol(c, state, 0) + 1;
404 
405  if (len > 128 - i)
406  return AVERROR_INVALIDDATA;
407 
408  while (len--) {
409  quant_table[i] = scale * v;
410  i++;
411  }
412  }
413 
414  for (i = 1; i < 128; i++)
415  quant_table[256 - i] = -quant_table[i];
416  quant_table[128] = -quant_table[127];
417 
418  return 2 * v - 1;
419 }
420 
422  int16_t quant_table[MAX_CONTEXT_INPUTS][256])
423 {
424  int i;
425  int context_count = 1;
426 
427  for (i = 0; i < 5; i++) {
428  context_count *= read_quant_table(c, quant_table[i], context_count);
429  if (context_count > 32768U) {
430  return AVERROR_INVALIDDATA;
431  }
432  }
433  return (context_count + 1) / 2;
434 }
435 
437 {
438  RangeCoder *const c = &f->c;
440  int i, j, k, ret;
441  uint8_t state2[32][CONTEXT_SIZE];
442 
443  memset(state2, 128, sizeof(state2));
444  memset(state, 128, sizeof(state));
445 
447  ff_build_rac_states(c, 0.05 * (1LL << 32), 256 - 8);
448 
449  f->version = get_symbol(c, state, 0);
450  if (f->version > 2) {
451  c->bytestream_end -= 4;
452  f->minor_version = get_symbol(c, state, 0);
453  }
454  f->ac = f->avctx->coder_type = get_symbol(c, state, 0);
455  if (f->ac > 1) {
456  for (i = 1; i < 256; i++)
457  f->state_transition[i] = get_symbol(c, state, 1) + c->one_state[i];
458  }
459 
460  f->colorspace = get_symbol(c, state, 0); //YUV cs type
461  f->avctx->bits_per_raw_sample = get_symbol(c, state, 0);
462  f->chroma_planes = get_rac(c, state);
463  f->chroma_h_shift = get_symbol(c, state, 0);
464  f->chroma_v_shift = get_symbol(c, state, 0);
465  f->transparency = get_rac(c, state);
466  f->plane_count = 2 + f->transparency;
467  f->num_h_slices = 1 + get_symbol(c, state, 0);
468  f->num_v_slices = 1 + get_symbol(c, state, 0);
469 
470  if (f->num_h_slices > (unsigned)f->width || !f->num_h_slices ||
471  f->num_v_slices > (unsigned)f->height || !f->num_v_slices
472  ) {
473  av_log(f->avctx, AV_LOG_ERROR, "slice count invalid\n");
474  return AVERROR_INVALIDDATA;
475  }
476 
477  f->quant_table_count = get_symbol(c, state, 0);
478  if (f->quant_table_count > (unsigned)MAX_QUANT_TABLES)
479  return AVERROR_INVALIDDATA;
480 
481  for (i = 0; i < f->quant_table_count; i++) {
482  f->context_count[i] = read_quant_tables(c, f->quant_tables[i]);
483  if (f->context_count[i] < 0) {
484  av_log(f->avctx, AV_LOG_ERROR, "read_quant_table error\n");
485  return AVERROR_INVALIDDATA;
486  }
487  }
488  if ((ret = ffv1_allocate_initial_states(f)) < 0)
489  return ret;
490 
491  for (i = 0; i < f->quant_table_count; i++)
492  if (get_rac(c, state)) {
493  for (j = 0; j < f->context_count[i]; j++)
494  for (k = 0; k < CONTEXT_SIZE; k++) {
495  int pred = j ? f->initial_states[i][j - 1][k] : 128;
496  f->initial_states[i][j][k] =
497  (pred + get_symbol(c, state2[k], 1)) & 0xFF;
498  }
499  }
500 
501  if (f->version > 2) {
502  f->ec = get_symbol(c, state, 0);
503  }
504 
505  if (f->version > 2) {
506  unsigned v;
509  if (v) {
510  av_log(f->avctx, AV_LOG_ERROR, "CRC mismatch %X!\n", v);
511  return AVERROR_INVALIDDATA;
512  }
513  }
514 
515  return 0;
516 }
517 
518 static int read_header(FFV1Context *f)
519 {
521  int i, j, context_count = -1; //-1 to avoid warning
522  RangeCoder *const c = &f->slice_context[0]->c;
523 
524  memset(state, 128, sizeof(state));
525 
526  if (f->version < 2) {
527  unsigned v= get_symbol(c, state, 0);
528  if (v >= 2) {
529  av_log(f->avctx, AV_LOG_ERROR, "invalid version %d in ver01 header\n", v);
530  return AVERROR_INVALIDDATA;
531  }
532  f->version = v;
533  f->ac = f->avctx->coder_type = get_symbol(c, state, 0);
534  if (f->ac > 1) {
535  for (i = 1; i < 256; i++)
536  f->state_transition[i] = get_symbol(c, state, 1) + c->one_state[i];
537  }
538 
539  f->colorspace = get_symbol(c, state, 0); //YUV cs type
540 
541  if (f->version > 0)
542  f->avctx->bits_per_raw_sample = get_symbol(c, state, 0);
543 
544  f->chroma_planes = get_rac(c, state);
545  f->chroma_h_shift = get_symbol(c, state, 0);
546  f->chroma_v_shift = get_symbol(c, state, 0);
547  f->transparency = get_rac(c, state);
548  f->plane_count = 2 + f->transparency;
549  }
550 
551  if (f->colorspace == 0) {
552  if (!f->transparency && !f->chroma_planes) {
553  if (f->avctx->bits_per_raw_sample <= 8)
555  else
557  } else if (f->avctx->bits_per_raw_sample<=8 && !f->transparency) {
558  switch(16 * f->chroma_h_shift + f->chroma_v_shift) {
559  case 0x00: f->avctx->pix_fmt = AV_PIX_FMT_YUV444P; break;
560  case 0x01: f->avctx->pix_fmt = AV_PIX_FMT_YUV440P; break;
561  case 0x10: f->avctx->pix_fmt = AV_PIX_FMT_YUV422P; break;
562  case 0x11: f->avctx->pix_fmt = AV_PIX_FMT_YUV420P; break;
563  case 0x20: f->avctx->pix_fmt = AV_PIX_FMT_YUV411P; break;
564  case 0x22: f->avctx->pix_fmt = AV_PIX_FMT_YUV410P; break;
565  default:
566  av_log(f->avctx, AV_LOG_ERROR, "format not supported\n");
567  return AVERROR(ENOSYS);
568  }
569  } else if (f->avctx->bits_per_raw_sample <= 8 && f->transparency) {
570  switch(16*f->chroma_h_shift + f->chroma_v_shift) {
571  case 0x00: f->avctx->pix_fmt = AV_PIX_FMT_YUVA444P; break;
572  case 0x10: f->avctx->pix_fmt = AV_PIX_FMT_YUVA422P; break;
573  case 0x11: f->avctx->pix_fmt = AV_PIX_FMT_YUVA420P; break;
574  default:
575  av_log(f->avctx, AV_LOG_ERROR, "format not supported\n");
576  return AVERROR(ENOSYS);
577  }
578  } else if (f->avctx->bits_per_raw_sample == 9) {
579  f->packed_at_lsb = 1;
580  switch(16 * f->chroma_h_shift + f->chroma_v_shift) {
581  case 0x00: f->avctx->pix_fmt = AV_PIX_FMT_YUV444P9; break;
582  case 0x10: f->avctx->pix_fmt = AV_PIX_FMT_YUV422P9; break;
583  case 0x11: f->avctx->pix_fmt = AV_PIX_FMT_YUV420P9; break;
584  default:
585  av_log(f->avctx, AV_LOG_ERROR, "format not supported\n");
586  return AVERROR(ENOSYS);
587  }
588  } else if (f->avctx->bits_per_raw_sample == 10) {
589  f->packed_at_lsb = 1;
590  switch(16 * f->chroma_h_shift + f->chroma_v_shift) {
591  case 0x00: f->avctx->pix_fmt = AV_PIX_FMT_YUV444P10; break;
592  case 0x10: f->avctx->pix_fmt = AV_PIX_FMT_YUV422P10; break;
593  case 0x11: f->avctx->pix_fmt = AV_PIX_FMT_YUV420P10; break;
594  default:
595  av_log(f->avctx, AV_LOG_ERROR, "format not supported\n");
596  return AVERROR(ENOSYS);
597  }
598  } else {
599  switch(16 * f->chroma_h_shift + f->chroma_v_shift) {
600  case 0x00: f->avctx->pix_fmt = AV_PIX_FMT_YUV444P16; break;
601  case 0x10: f->avctx->pix_fmt = AV_PIX_FMT_YUV422P16; break;
602  case 0x11: f->avctx->pix_fmt = AV_PIX_FMT_YUV420P16; break;
603  default:
604  av_log(f->avctx, AV_LOG_ERROR, "format not supported\n");
605  return AVERROR(ENOSYS);
606  }
607  }
608  } else if (f->colorspace == 1) {
609  if (f->chroma_h_shift || f->chroma_v_shift) {
611  "chroma subsampling not supported in this colorspace\n");
612  return AVERROR(ENOSYS);
613  }
614  if ( f->avctx->bits_per_raw_sample == 9)
616  else if (f->avctx->bits_per_raw_sample == 10)
618  else if (f->avctx->bits_per_raw_sample == 12)
620  else if (f->avctx->bits_per_raw_sample == 14)
622  else
624  else f->avctx->pix_fmt = AV_PIX_FMT_0RGB32;
625  } else {
626  av_log(f->avctx, AV_LOG_ERROR, "colorspace not supported\n");
627  return AVERROR(ENOSYS);
628  }
629 
630  av_dlog(f->avctx, "%d %d %d\n",
632  if (f->version < 2) {
633  context_count = read_quant_tables(c, f->quant_table);
634  if (context_count < 0) {
635  av_log(f->avctx, AV_LOG_ERROR, "read_quant_table error\n");
636  return AVERROR_INVALIDDATA;
637  }
638  } else if (f->version < 3) {
639  f->slice_count = get_symbol(c, state, 0);
640  } else {
641  const uint8_t *p = c->bytestream_end;
642  for (f->slice_count = 0;
643  f->slice_count < MAX_SLICES && 3 < p - c->bytestream_start;
644  f->slice_count++) {
645  int trailer = 3 + 5*!!f->ec;
646  int size = AV_RB24(p-trailer);
647  if (size + trailer > p - c->bytestream_start)
648  break;
649  p -= size + trailer;
650  }
651  }
652  if (f->slice_count > (unsigned)MAX_SLICES || f->slice_count <= 0) {
653  av_log(f->avctx, AV_LOG_ERROR, "slice count %d is invalid\n", f->slice_count);
654  return AVERROR_INVALIDDATA;
655  }
656 
657  for (j = 0; j < f->slice_count; j++) {
658  FFV1Context *fs = f->slice_context[j];
659  fs->ac = f->ac;
660  fs->packed_at_lsb = f->packed_at_lsb;
661 
662  fs->slice_damaged = 0;
663 
664  if (f->version == 2) {
665  fs->slice_x = get_symbol(c, state, 0) * f->width ;
666  fs->slice_y = get_symbol(c, state, 0) * f->height;
667  fs->slice_width = (get_symbol(c, state, 0) + 1) * f->width + fs->slice_x;
668  fs->slice_height = (get_symbol(c, state, 0) + 1) * f->height + fs->slice_y;
669 
670  fs->slice_x /= f->num_h_slices;
671  fs->slice_y /= f->num_v_slices;
672  fs->slice_width = fs->slice_width / f->num_h_slices - fs->slice_x;
673  fs->slice_height = fs->slice_height / f->num_v_slices - fs->slice_y;
674  if ((unsigned)fs->slice_width > f->width ||
675  (unsigned)fs->slice_height > f->height)
676  return AVERROR_INVALIDDATA;
677  if ( (unsigned)fs->slice_x + (uint64_t)fs->slice_width > f->width
678  || (unsigned)fs->slice_y + (uint64_t)fs->slice_height > f->height)
679  return AVERROR_INVALIDDATA;
680  }
681 
682  for (i = 0; i < f->plane_count; i++) {
683  PlaneContext *const p = &fs->plane[i];
684 
685  if (f->version == 2) {
686  int idx = get_symbol(c, state, 0);
687  if (idx > (unsigned)f->quant_table_count) {
689  "quant_table_index out of range\n");
690  return AVERROR_INVALIDDATA;
691  }
692  p->quant_table_index = idx;
693  memcpy(p->quant_table, f->quant_tables[idx],
694  sizeof(p->quant_table));
695  context_count = f->context_count[idx];
696  } else {
697  memcpy(p->quant_table, f->quant_table, sizeof(p->quant_table));
698  }
699 
700  if (f->version <= 2) {
701  av_assert0(context_count >= 0);
702  if (p->context_count < context_count) {
703  av_freep(&p->state);
704  av_freep(&p->vlc_state);
705  }
707  }
708  }
709  }
710  return 0;
711 }
712 
714 {
715  FFV1Context *f = avctx->priv_data;
716  int ret;
717 
718  if ((ret = ffv1_common_init(avctx)) < 0)
719  return ret;
720 
721  if (avctx->extradata && (ret = read_extra_header(f)) < 0)
722  return ret;
723 
724  if ((ret = ffv1_init_slice_contexts(f)) < 0)
725  return ret;
726 
727  return 0;
728 }
729 
730 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
731 {
732  const uint8_t *buf = avpkt->data;
733  int buf_size = avpkt->size;
734  FFV1Context *f = avctx->priv_data;
735  RangeCoder *const c = &f->slice_context[0]->c;
736  AVFrame *const p = &f->picture;
737  int i, ret;
738  uint8_t keystate = 128;
739  const uint8_t *buf_p;
740 
741  AVFrame *picture = data;
742 
743  /* release previously stored data */
744  if (p->data[0])
745  avctx->release_buffer(avctx, p);
746 
747  ff_init_range_decoder(c, buf, buf_size);
748  ff_build_rac_states(c, 0.05 * (1LL << 32), 256 - 8);
749 
750  p->pict_type = AV_PICTURE_TYPE_I; //FIXME I vs. P
751  if (get_rac(c, &keystate)) {
752  p->key_frame = 1;
753  f->key_frame_ok = 0;
754  if ((ret = read_header(f)) < 0)
755  return ret;
756  f->key_frame_ok = 1;
757  } else {
758  if (!f->key_frame_ok) {
759  av_log(avctx, AV_LOG_ERROR,
760  "Cannot decode non-keyframe without valid keyframe\n");
761  return AVERROR_INVALIDDATA;
762  }
763  p->key_frame = 0;
764  }
765 
766  p->reference = 3; //for error concealment
767  if ((ret = ff_get_buffer(avctx, p)) < 0) {
768  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
769  return ret;
770  }
771 
772  if (avctx->debug & FF_DEBUG_PICT_INFO)
773  av_log(avctx, AV_LOG_DEBUG, "ver:%d keyframe:%d coder:%d ec:%d slices:%d bps:%d\n",
774  f->version, p->key_frame, f->ac, f->ec, f->slice_count, f->avctx->bits_per_raw_sample);
775 
776  buf_p = buf + buf_size;
777  for (i = f->slice_count - 1; i >= 0; i--) {
778  FFV1Context *fs = f->slice_context[i];
779  int trailer = 3 + 5*!!f->ec;
780  int v;
781 
782  if (i || f->version > 2) v = AV_RB24(buf_p-trailer) + trailer;
783  else v = buf_p - c->bytestream_start;
784  if (buf_p - c->bytestream_start < v) {
785  av_log(avctx, AV_LOG_ERROR, "Slice pointer chain broken\n");
786  return AVERROR_INVALIDDATA;
787  }
788  buf_p -= v;
789 
790  if (f->ec) {
791  unsigned crc = av_crc(av_crc_get_table(AV_CRC_32_IEEE), 0, buf_p, v);
792  if (crc) {
793  int64_t ts = avpkt->pts != AV_NOPTS_VALUE ? avpkt->pts : avpkt->dts;
794  av_log(f->avctx, AV_LOG_ERROR, "CRC mismatch %X!", crc);
795  if (ts != AV_NOPTS_VALUE && avctx->pkt_timebase.num) {
796  av_log(f->avctx, AV_LOG_ERROR, "at %f seconds\n", ts*av_q2d(avctx->pkt_timebase));
797  } else if (ts != AV_NOPTS_VALUE) {
798  av_log(f->avctx, AV_LOG_ERROR, "at %"PRId64"\n", ts);
799  } else {
800  av_log(f->avctx, AV_LOG_ERROR, "\n");
801  }
802  fs->slice_damaged = 1;
803  }
804  }
805 
806  if (i) {
807  ff_init_range_decoder(&fs->c, buf_p, v);
808  } else
809  fs->c.bytestream_end = (uint8_t *)(buf_p + v);
810  }
811 
812  avctx->execute(avctx,
813  decode_slice,
814  &f->slice_context[0],
815  NULL,
816  f->slice_count,
817  sizeof(void*));
818 
819  for (i = f->slice_count - 1; i >= 0; i--) {
820  FFV1Context *fs = f->slice_context[i];
821  int j;
822  if (fs->slice_damaged && f->last_picture.data[0]) {
823  const uint8_t *src[4];
824  uint8_t *dst[4];
825  for (j = 0; j < 4; j++) {
826  int sh = (j==1 || j==2) ? f->chroma_h_shift : 0;
827  int sv = (j==1 || j==2) ? f->chroma_v_shift : 0;
828  dst[j] = f->picture .data[j] + f->picture .linesize[j]*
829  (fs->slice_y>>sv) + (fs->slice_x>>sh);
830  src[j] = f->last_picture.data[j] + f->last_picture.linesize[j]*
831  (fs->slice_y>>sv) + (fs->slice_x>>sh);
832  }
833  av_image_copy(dst,
834  f->picture.linesize,
835  (const uint8_t **)src,
837  avctx->pix_fmt,
838  fs->slice_width,
839  fs->slice_height);
840  }
841  }
842 
843  f->picture_number++;
844 
845  *picture = *p;
846  *got_frame = 1;
847 
849 
850  return buf_size;
851 }
852 
854  .name = "ffv1",
855  .type = AVMEDIA_TYPE_VIDEO,
856  .id = AV_CODEC_ID_FFV1,
857  .priv_data_size = sizeof(FFV1Context),
858  .init = decode_init,
859  .close = ffv1_close,
860  .decode = decode_frame,
861  .capabilities = CODEC_CAP_DR1 /*| CODEC_CAP_DRAW_HORIZ_BAND*/ |
863  .long_name = NULL_IF_CONFIG_SMALL("FFmpeg video codec #1"),
864 };