FFmpeg
dvdec.c
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1 /*
2  * DV decoder
3  * Copyright (c) 2002 Fabrice Bellard
4  * Copyright (c) 2004 Roman Shaposhnik
5  *
6  * 50 Mbps (DVCPRO50) support
7  * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>
8  *
9  * 100 Mbps (DVCPRO HD) support
10  * Initial code by Daniel Maas <dmaas@maasdigital.com> (funded by BBC R&D)
11  * Final code by Roman Shaposhnik
12  *
13  * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
14  * of DV technical info.
15  *
16  * This file is part of FFmpeg.
17  *
18  * FFmpeg is free software; you can redistribute it and/or
19  * modify it under the terms of the GNU Lesser General Public
20  * License as published by the Free Software Foundation; either
21  * version 2.1 of the License, or (at your option) any later version.
22  *
23  * FFmpeg is distributed in the hope that it will be useful,
24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
26  * Lesser General Public License for more details.
27  *
28  * You should have received a copy of the GNU Lesser General Public
29  * License along with FFmpeg; if not, write to the Free Software
30  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
31  */
32 
33 /**
34  * @file
35  * DV decoder
36  */
37 
38 #include "libavutil/avassert.h"
39 #include "libavutil/imgutils.h"
40 #include "libavutil/internal.h"
41 #include "libavutil/pixdesc.h"
42 
43 #include "avcodec.h"
44 #include "dv.h"
45 #include "dv_profile_internal.h"
46 #include "dvdata.h"
47 #include "get_bits.h"
48 #include "idctdsp.h"
49 #include "internal.h"
50 #include "put_bits.h"
51 #include "simple_idct.h"
52 #include "thread.h"
53 
54 typedef struct BlockInfo {
55  const uint32_t *factor_table;
56  const uint8_t *scan_table;
57  uint8_t pos; /* position in block */
58  void (*idct_put)(uint8_t *dest, ptrdiff_t stride, int16_t *block);
59  uint8_t partial_bit_count;
60  uint32_t partial_bit_buffer;
61  int shift_offset;
62 } BlockInfo;
63 
64 static const int dv_iweight_bits = 14;
65 
66 static const uint16_t dv_iweight_88[64] = {
67  32768, 16705, 16705, 17734, 17032, 17734, 18205, 18081,
68  18081, 18205, 18725, 18562, 19195, 18562, 18725, 19266,
69  19091, 19705, 19705, 19091, 19266, 21407, 19643, 20267,
70  20228, 20267, 19643, 21407, 22725, 21826, 20853, 20806,
71  20806, 20853, 21826, 22725, 23170, 23170, 21407, 21400,
72  21407, 23170, 23170, 24598, 23786, 22018, 22018, 23786,
73  24598, 25251, 24465, 22654, 24465, 25251, 25972, 25172,
74  25172, 25972, 26722, 27969, 26722, 29692, 29692, 31521,
75 };
76 static const uint16_t dv_iweight_248[64] = {
77  32768, 16384, 16705, 16705, 17734, 17734, 17734, 17734,
78  18081, 18081, 18725, 18725, 21407, 21407, 19091, 19091,
79  19195, 19195, 18205, 18205, 18725, 18725, 19705, 19705,
80  20267, 20267, 21826, 21826, 23170, 23170, 20806, 20806,
81  20267, 20267, 19266, 19266, 21407, 21407, 20853, 20853,
82  21400, 21400, 23786, 23786, 24465, 24465, 22018, 22018,
83  23170, 23170, 22725, 22725, 24598, 24598, 24465, 24465,
84  25172, 25172, 27969, 27969, 25972, 25972, 29692, 29692
85 };
86 
87 /**
88  * The "inverse" DV100 weights are actually just the spec weights (zig-zagged).
89  */
90 static const uint16_t dv_iweight_1080_y[64] = {
91  128, 16, 16, 17, 17, 17, 18, 18,
92  18, 18, 18, 18, 19, 18, 18, 19,
93  19, 19, 19, 19, 19, 42, 38, 40,
94  40, 40, 38, 42, 44, 43, 41, 41,
95  41, 41, 43, 44, 45, 45, 42, 42,
96  42, 45, 45, 48, 46, 43, 43, 46,
97  48, 49, 48, 44, 48, 49, 101, 98,
98  98, 101, 104, 109, 104, 116, 116, 123,
99 };
100 static const uint16_t dv_iweight_1080_c[64] = {
101  128, 16, 16, 17, 17, 17, 25, 25,
102  25, 25, 26, 25, 26, 25, 26, 26,
103  26, 27, 27, 26, 26, 42, 38, 40,
104  40, 40, 38, 42, 44, 43, 41, 41,
105  41, 41, 43, 44, 91, 91, 84, 84,
106  84, 91, 91, 96, 93, 86, 86, 93,
107  96, 197, 191, 177, 191, 197, 203, 197,
108  197, 203, 209, 219, 209, 232, 232, 246,
109 };
110 static const uint16_t dv_iweight_720_y[64] = {
111  128, 16, 16, 17, 17, 17, 18, 18,
112  18, 18, 18, 18, 19, 18, 18, 19,
113  19, 19, 19, 19, 19, 42, 38, 40,
114  40, 40, 38, 42, 44, 43, 41, 41,
115  41, 41, 43, 44, 68, 68, 63, 63,
116  63, 68, 68, 96, 92, 86, 86, 92,
117  96, 98, 96, 88, 96, 98, 202, 196,
118  196, 202, 208, 218, 208, 232, 232, 246,
119 };
120 static const uint16_t dv_iweight_720_c[64] = {
121  128, 24, 24, 26, 26, 26, 36, 36,
122  36, 36, 36, 36, 38, 36, 36, 38,
123  38, 38, 38, 38, 38, 84, 76, 80,
124  80, 80, 76, 84, 88, 86, 82, 82,
125  82, 82, 86, 88, 182, 182, 168, 168,
126  168, 182, 182, 192, 186, 192, 172, 186,
127  192, 394, 382, 354, 382, 394, 406, 394,
128  394, 406, 418, 438, 418, 464, 464, 492,
129 };
130 
131 static void dv_init_weight_tables(DVVideoContext *ctx, const AVDVProfile *d)
132 {
133  int j, i, c, s;
134  uint32_t *factor1 = &ctx->idct_factor[0],
135  *factor2 = &ctx->idct_factor[DV_PROFILE_IS_HD(d) ? 4096 : 2816];
136 
137  if (DV_PROFILE_IS_HD(d)) {
138  /* quantization quanta by QNO for DV100 */
139  static const uint8_t dv100_qstep[16] = {
140  1, /* QNO = 0 and 1 both have no quantization */
141  1,
142  2, 3, 4, 5, 6, 7, 8, 16, 18, 20, 22, 24, 28, 52
143  };
144  const uint16_t *iweight1, *iweight2;
145 
146  if (d->height == 720) {
147  iweight1 = &dv_iweight_720_y[0];
148  iweight2 = &dv_iweight_720_c[0];
149  } else {
150  iweight1 = &dv_iweight_1080_y[0];
151  iweight2 = &dv_iweight_1080_c[0];
152  }
153  for (c = 0; c < 4; c++) {
154  for (s = 0; s < 16; s++) {
155  for (i = 0; i < 64; i++) {
156  *factor1++ = (dv100_qstep[s] << (c + 9)) * iweight1[i];
157  *factor2++ = (dv100_qstep[s] << (c + 9)) * iweight2[i];
158  }
159  }
160  }
161  } else {
162  static const uint8_t dv_quant_areas[4] = { 6, 21, 43, 64 };
163  const uint16_t *iweight1 = &dv_iweight_88[0];
164  for (j = 0; j < 2; j++, iweight1 = &dv_iweight_248[0]) {
165  for (s = 0; s < 22; s++) {
166  for (i = c = 0; c < 4; c++) {
167  for (; i < dv_quant_areas[c]; i++) {
168  *factor1 = iweight1[i] << (ff_dv_quant_shifts[s][c] + 1);
169  *factor2++ = (*factor1++) << 1;
170  }
171  }
172  }
173  }
174  }
175 }
176 
177 static av_cold int dvvideo_decode_init(AVCodecContext *avctx)
178 {
179  DVVideoContext *s = avctx->priv_data;
180  IDCTDSPContext idsp;
181  int i;
182 
183  memset(&idsp,0, sizeof(idsp));
184  ff_idctdsp_init(&idsp, avctx);
185 
186  for (i = 0; i < 64; i++)
187  s->dv_zigzag[0][i] = idsp.idct_permutation[ff_zigzag_direct[i]];
188 
189  if (avctx->lowres){
190  for (i = 0; i < 64; i++){
191  int j = ff_dv_zigzag248_direct[i];
192  s->dv_zigzag[1][i] = idsp.idct_permutation[(j & 7) + (j & 8) * 4 + (j & 48) / 2];
193  }
194  }else
195  memcpy(s->dv_zigzag[1], ff_dv_zigzag248_direct, sizeof(s->dv_zigzag[1]));
196 
197  s->idct_put[0] = idsp.idct_put;
198  s->idct_put[1] = ff_simple_idct248_put;
199 
200  return ff_dvvideo_init(avctx);
201 }
202 
203 /* decode AC coefficients */
204 static void dv_decode_ac(GetBitContext *gb, BlockInfo *mb, int16_t *block)
205 {
206  int last_index = gb->size_in_bits;
207  const uint8_t *scan_table = mb->scan_table;
208  const uint32_t *factor_table = mb->factor_table;
209  int pos = mb->pos;
210  int partial_bit_count = mb->partial_bit_count;
211  int level, run, vlc_len, index;
212 
213  OPEN_READER_NOSIZE(re, gb);
214  UPDATE_CACHE(re, gb);
215 
216  /* if we must parse a partial VLC, we do it here */
217  if (partial_bit_count > 0) {
218  re_cache = re_cache >> partial_bit_count |
219  mb->partial_bit_buffer;
220  re_index -= partial_bit_count;
221  mb->partial_bit_count = 0;
222  }
223 
224  /* get the AC coefficients until last_index is reached */
225  for (;;) {
226  ff_dlog(NULL, "%2d: bits=%04"PRIx32" index=%u\n",
227  pos, SHOW_UBITS(re, gb, 16), re_index);
228  /* our own optimized GET_RL_VLC */
229  index = NEG_USR32(re_cache, TEX_VLC_BITS);
230  vlc_len = ff_dv_rl_vlc[index].len;
231  if (vlc_len < 0) {
232  index = NEG_USR32((unsigned) re_cache << TEX_VLC_BITS, -vlc_len) +
233  ff_dv_rl_vlc[index].level;
234  vlc_len = TEX_VLC_BITS - vlc_len;
235  }
236  level = ff_dv_rl_vlc[index].level;
237  run = ff_dv_rl_vlc[index].run;
238 
239  /* gotta check if we're still within gb boundaries */
240  if (re_index + vlc_len > last_index) {
241  /* should be < 16 bits otherwise a codeword could have been parsed */
242  mb->partial_bit_count = last_index - re_index;
243  mb->partial_bit_buffer = re_cache & ~(-1u >> mb->partial_bit_count);
244  re_index = last_index;
245  break;
246  }
247  re_index += vlc_len;
248 
249  ff_dlog(NULL, "run=%d level=%d\n", run, level);
250  pos += run;
251  if (pos >= 64)
252  break;
253 
254  level = (level * factor_table[pos] + (1 << (dv_iweight_bits - 1))) >>
255  dv_iweight_bits;
256  block[scan_table[pos]] = level;
257 
258  UPDATE_CACHE(re, gb);
259  }
260  CLOSE_READER(re, gb);
261  mb->pos = pos;
262 }
263 
264 static inline void bit_copy(PutBitContext *pb, GetBitContext *gb)
265 {
266  int bits_left = get_bits_left(gb);
267  while (bits_left >= MIN_CACHE_BITS) {
268  put_bits(pb, MIN_CACHE_BITS, get_bits(gb, MIN_CACHE_BITS));
269  bits_left -= MIN_CACHE_BITS;
270  }
271  if (bits_left > 0)
272  put_bits(pb, bits_left, get_bits(gb, bits_left));
273 }
274 
275 /* mb_x and mb_y are in units of 8 pixels */
276 static int dv_decode_video_segment(AVCodecContext *avctx, void *arg)
277 {
278  DVVideoContext *s = avctx->priv_data;
279  DVwork_chunk *work_chunk = arg;
280  int quant, dc, dct_mode, class1, j;
281  int mb_index, mb_x, mb_y, last_index;
282  int y_stride, linesize;
283  int16_t *block, *block1;
284  int c_offset;
285  uint8_t *y_ptr;
286  const uint8_t *buf_ptr;
287  PutBitContext pb, vs_pb;
288  GetBitContext gb;
289  BlockInfo mb_data[5 * DV_MAX_BPM], *mb, *mb1;
290  LOCAL_ALIGNED_16(int16_t, sblock, [5 * DV_MAX_BPM], [64]);
291  LOCAL_ALIGNED_16(uint8_t, mb_bit_buffer, [80 + AV_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */
292  LOCAL_ALIGNED_16(uint8_t, vs_bit_buffer, [80 * 5 + AV_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */
293  const int log2_blocksize = 3-s->avctx->lowres;
294  int is_field_mode[5];
295  int vs_bit_buffer_damaged = 0;
296  int mb_bit_buffer_damaged[5] = {0};
297  int retried = 0;
298  int sta;
299 
300  av_assert1((((int) mb_bit_buffer) & 7) == 0);
301  av_assert1((((int) vs_bit_buffer) & 7) == 0);
302 
303 retry:
304 
305  memset(sblock, 0, 5 * DV_MAX_BPM * sizeof(*sblock));
306 
307  /* pass 1: read DC and AC coefficients in blocks */
308  buf_ptr = &s->buf[work_chunk->buf_offset * 80];
309  block1 = &sblock[0][0];
310  mb1 = mb_data;
311  init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80);
312  for (mb_index = 0; mb_index < 5; mb_index++, mb1 += s->sys->bpm, block1 += s->sys->bpm * 64) {
313  /* skip header */
314  quant = buf_ptr[3] & 0x0f;
315  if (avctx->error_concealment) {
316  if ((buf_ptr[3] >> 4) == 0x0E)
317  vs_bit_buffer_damaged = 1;
318  if (!mb_index) {
319  sta = buf_ptr[3] >> 4;
320  } else if (sta != (buf_ptr[3] >> 4))
321  vs_bit_buffer_damaged = 1;
322  }
323  buf_ptr += 4;
324  init_put_bits(&pb, mb_bit_buffer, 80);
325  mb = mb1;
326  block = block1;
327  is_field_mode[mb_index] = 0;
328  for (j = 0; j < s->sys->bpm; j++) {
329  last_index = s->sys->block_sizes[j];
330  init_get_bits(&gb, buf_ptr, last_index);
331 
332  /* get the DC */
333  dc = get_sbits(&gb, 9);
334  dct_mode = get_bits1(&gb);
335  class1 = get_bits(&gb, 2);
336  if (DV_PROFILE_IS_HD(s->sys)) {
337  mb->idct_put = s->idct_put[0];
338  mb->scan_table = s->dv_zigzag[0];
339  mb->factor_table = &s->idct_factor[(j >= 4) * 4 * 16 * 64 +
340  class1 * 16 * 64 +
341  quant * 64];
342  is_field_mode[mb_index] |= !j && dct_mode;
343  } else {
344  mb->idct_put = s->idct_put[dct_mode && log2_blocksize == 3];
345  mb->scan_table = s->dv_zigzag[dct_mode];
346  mb->factor_table =
347  &s->idct_factor[(class1 == 3) * 2 * 22 * 64 +
348  dct_mode * 22 * 64 +
349  (quant + ff_dv_quant_offset[class1]) * 64];
350  }
351  dc = dc * 4;
352  /* convert to unsigned because 128 is not added in the
353  * standard IDCT */
354  dc += 1024;
355  block[0] = dc;
356  buf_ptr += last_index >> 3;
357  mb->pos = 0;
358  mb->partial_bit_count = 0;
359 
360  ff_dlog(avctx, "MB block: %d, %d ", mb_index, j);
361  dv_decode_ac(&gb, mb, block);
362 
363  /* write the remaining bits in a new buffer only if the
364  * block is finished */
365  if (mb->pos >= 64)
366  bit_copy(&pb, &gb);
367  if (mb->pos >= 64 && mb->pos < 127)
368  vs_bit_buffer_damaged = mb_bit_buffer_damaged[mb_index] = 1;
369 
370  block += 64;
371  mb++;
372  }
373 
374  if (mb_bit_buffer_damaged[mb_index] > 0)
375  continue;
376 
377  /* pass 2: we can do it just after */
378  ff_dlog(avctx, "***pass 2 size=%d MB#=%d\n", put_bits_count(&pb), mb_index);
379  block = block1;
380  mb = mb1;
381  init_get_bits(&gb, mb_bit_buffer, put_bits_count(&pb));
382  put_bits32(&pb, 0); // padding must be zeroed
383  flush_put_bits(&pb);
384  for (j = 0; j < s->sys->bpm; j++, block += 64, mb++) {
385  if (mb->pos < 64 && get_bits_left(&gb) > 0) {
386  dv_decode_ac(&gb, mb, block);
387  /* if still not finished, no need to parse other blocks */
388  if (mb->pos < 64)
389  break;
390  if (mb->pos < 127)
391  vs_bit_buffer_damaged = mb_bit_buffer_damaged[mb_index] = 1;
392  }
393  }
394  /* all blocks are finished, so the extra bytes can be used at
395  * the video segment level */
396  if (j >= s->sys->bpm)
397  bit_copy(&vs_pb, &gb);
398  }
399 
400  /* we need a pass over the whole video segment */
401  ff_dlog(avctx, "***pass 3 size=%d\n", put_bits_count(&vs_pb));
402  block = &sblock[0][0];
403  mb = mb_data;
404  init_get_bits(&gb, vs_bit_buffer, put_bits_count(&vs_pb));
405  put_bits32(&vs_pb, 0); // padding must be zeroed
406  flush_put_bits(&vs_pb);
407  for (mb_index = 0; mb_index < 5; mb_index++) {
408  for (j = 0; j < s->sys->bpm; j++) {
409  if (mb->pos < 64 && get_bits_left(&gb) > 0 && !vs_bit_buffer_damaged) {
410  ff_dlog(avctx, "start %d:%d\n", mb_index, j);
411  dv_decode_ac(&gb, mb, block);
412  }
413 
414  if (mb->pos >= 64 && mb->pos < 127) {
415  av_log(avctx, AV_LOG_ERROR,
416  "AC EOB marker is absent pos=%d\n", mb->pos);
417  vs_bit_buffer_damaged = 1;
418  }
419  block += 64;
420  mb++;
421  }
422  }
423  if (vs_bit_buffer_damaged && !retried) {
424  av_log(avctx, AV_LOG_ERROR, "Concealing bitstream errors\n");
425  retried = 1;
426  goto retry;
427  }
428 
429  /* compute idct and place blocks */
430  block = &sblock[0][0];
431  mb = mb_data;
432  for (mb_index = 0; mb_index < 5; mb_index++) {
433  dv_calculate_mb_xy(s, work_chunk, mb_index, &mb_x, &mb_y);
434 
435  /* idct_put'ting luminance */
436  if ((s->sys->pix_fmt == AV_PIX_FMT_YUV420P) ||
437  (s->sys->pix_fmt == AV_PIX_FMT_YUV411P && mb_x >= (704 / 8)) ||
438  (s->sys->height >= 720 && mb_y != 134)) {
439  y_stride = (s->frame->linesize[0] <<
440  ((!is_field_mode[mb_index]) * log2_blocksize));
441  } else {
442  y_stride = (2 << log2_blocksize);
443  }
444  y_ptr = s->frame->data[0] +
445  ((mb_y * s->frame->linesize[0] + mb_x) << log2_blocksize);
446  linesize = s->frame->linesize[0] << is_field_mode[mb_index];
447  mb[0].idct_put(y_ptr, linesize, block + 0 * 64);
448  if (s->sys->video_stype == 4) { /* SD 422 */
449  mb[2].idct_put(y_ptr + (1 << log2_blocksize), linesize, block + 2 * 64);
450  } else {
451  mb[1].idct_put(y_ptr + (1 << log2_blocksize), linesize, block + 1 * 64);
452  mb[2].idct_put(y_ptr + y_stride, linesize, block + 2 * 64);
453  mb[3].idct_put(y_ptr + (1 << log2_blocksize) + y_stride, linesize, block + 3 * 64);
454  }
455  mb += 4;
456  block += 4 * 64;
457 
458  /* idct_put'ting chrominance */
459  c_offset = (((mb_y >> (s->sys->pix_fmt == AV_PIX_FMT_YUV420P)) * s->frame->linesize[1] +
460  (mb_x >> ((s->sys->pix_fmt == AV_PIX_FMT_YUV411P) ? 2 : 1))) << log2_blocksize);
461  for (j = 2; j; j--) {
462  uint8_t *c_ptr = s->frame->data[j] + c_offset;
463  if (s->sys->pix_fmt == AV_PIX_FMT_YUV411P && mb_x >= (704 / 8)) {
464  uint64_t aligned_pixels[64 / 8];
465  uint8_t *pixels = (uint8_t *) aligned_pixels;
466  uint8_t *c_ptr1, *ptr1;
467  int x, y;
468  mb->idct_put(pixels, 8, block);
469  for (y = 0; y < (1 << log2_blocksize); y++, c_ptr += s->frame->linesize[j], pixels += 8) {
470  ptr1 = pixels + ((1 << (log2_blocksize))>>1);
471  c_ptr1 = c_ptr + (s->frame->linesize[j] << log2_blocksize);
472  for (x = 0; x < (1 << FFMAX(log2_blocksize - 1, 0)); x++) {
473  c_ptr[x] = pixels[x];
474  c_ptr1[x] = ptr1[x];
475  }
476  }
477  block += 64;
478  mb++;
479  } else {
480  y_stride = (mb_y == 134) ? (1 << log2_blocksize) :
481  s->frame->linesize[j] << ((!is_field_mode[mb_index]) * log2_blocksize);
482  linesize = s->frame->linesize[j] << is_field_mode[mb_index];
483  (mb++)->idct_put(c_ptr, linesize, block);
484  block += 64;
485  if (s->sys->bpm == 8) {
486  (mb++)->idct_put(c_ptr + y_stride, linesize, block);
487  block += 64;
488  }
489  }
490  }
491  }
492  return 0;
493 }
494 
495 /* NOTE: exactly one frame must be given (120000 bytes for NTSC,
496  * 144000 bytes for PAL - or twice those for 50Mbps) */
497 static int dvvideo_decode_frame(AVCodecContext *avctx, void *data,
498  int *got_frame, AVPacket *avpkt)
499 {
500  uint8_t *buf = avpkt->data;
501  int buf_size = avpkt->size;
502  DVVideoContext *s = avctx->priv_data;
503  ThreadFrame frame = { .f = data };
504  const uint8_t *vsc_pack;
505  int apt, is16_9, ret;
506  const AVDVProfile *sys;
507 
508  sys = ff_dv_frame_profile(avctx, s->sys, buf, buf_size);
509  if (!sys || buf_size < sys->frame_size) {
510  av_log(avctx, AV_LOG_ERROR, "could not find dv frame profile\n");
511  return -1; /* NOTE: we only accept several full frames */
512  }
513 
514  if (sys != s->sys) {
515  ret = ff_dv_init_dynamic_tables(s, sys);
516  if (ret < 0) {
517  av_log(avctx, AV_LOG_ERROR, "Error initializing the work tables.\n");
518  return ret;
519  }
520  dv_init_weight_tables(s, sys);
521  s->sys = sys;
522  }
523 
524  s->frame = frame.f;
525  frame.f->key_frame = 1;
526  frame.f->pict_type = AV_PICTURE_TYPE_I;
527  avctx->pix_fmt = s->sys->pix_fmt;
528  avctx->framerate = av_inv_q(s->sys->time_base);
529 
530  ret = ff_set_dimensions(avctx, s->sys->width, s->sys->height);
531  if (ret < 0)
532  return ret;
533 
534  /* Determine the codec's sample_aspect ratio from the packet */
535  vsc_pack = buf + 80 * 5 + 48 + 5;
536  if (*vsc_pack == dv_video_control) {
537  apt = buf[4] & 0x07;
538  is16_9 = (vsc_pack[2] & 0x07) == 0x02 ||
539  (!apt && (vsc_pack[2] & 0x07) == 0x07);
540  ff_set_sar(avctx, s->sys->sar[is16_9]);
541  }
542 
543  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
544  return ret;
545  frame.f->interlaced_frame = 1;
546  frame.f->top_field_first = 0;
547 
548  /* Determine the codec's field order from the packet */
549  if ( *vsc_pack == dv_video_control ) {
550  frame.f->top_field_first = !(vsc_pack[3] & 0x40);
551  }
552 
553  s->buf = buf;
554  avctx->execute(avctx, dv_decode_video_segment, s->work_chunks, NULL,
555  dv_work_pool_size(s->sys), sizeof(DVwork_chunk));
556 
557  emms_c();
558 
559  /* return image */
560  *got_frame = 1;
561 
562  return s->sys->frame_size;
563 }
564 
565 AVCodec ff_dvvideo_decoder = {
566  .name = "dvvideo",
567  .long_name = NULL_IF_CONFIG_SMALL("DV (Digital Video)"),
568  .type = AVMEDIA_TYPE_VIDEO,
569  .id = AV_CODEC_ID_DVVIDEO,
570  .priv_data_size = sizeof(DVVideoContext),
571  .init = dvvideo_decode_init,
572  .decode = dvvideo_decode_frame,
573  .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS | AV_CODEC_CAP_SLICE_THREADS,
574  .max_lowres = 3,
575 };
AVCodec
AVCodec.
Definition: avcodec.h:3481
stride
int stride
Definition: mace.c:144
level
uint8_t level
Definition: svq3.c:207
DV_MAX_BPM
#define DV_MAX_BPM
maximum number of blocks per macroblock in any DV format
Definition: dv.h:94
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
get_bits_left
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:849
put_bits32
static void av_unused put_bits32(PutBitContext *s, uint32_t value)
Write exactly 32 bits into a bitstream.
Definition: put_bits.h:250
DVwork_chunk::buf_offset
uint16_t buf_offset
Definition: dv.h:36
dv_profile_internal.h
u
#define u(width, name, range_min, range_max)
Definition: cbs_h2645.c:252
ff_dv_frame_profile
const AVDVProfile * ff_dv_frame_profile(AVCodecContext *codec, const AVDVProfile *sys, const uint8_t *frame, unsigned buf_size)
Get a DV profile for the provided compressed frame.
Definition: dv_profile.c:260
init_put_bits
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:48
BlockInfo::pos
uint8_t pos
Definition: dvdec.c:57
GetBitContext::size_in_bits
int size_in_bits
Definition: get_bits.h:68
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:208
pixdesc.h
DVwork_chunk
Definition: dv.h:35
pixels
int pixels
Definition: avisynth_c.h:390
bit_copy
static void bit_copy(PutBitContext *pb, GetBitContext *gb)
Definition: dvdec.c:264
internal.h
AVPacket::data
uint8_t * data
Definition: avcodec.h:1477
RL_VLC_ELEM::run
uint8_t run
Definition: vlc.h:35
data
const char data[16]
Definition: mxf.c:91
UPDATE_CACHE
#define UPDATE_CACHE(name, gb)
Definition: get_bits.h:178
dv_init_weight_tables
static void dv_init_weight_tables(DVVideoContext *ctx, const AVDVProfile *d)
Definition: dvdec.c:131
init_get_bits
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:659
thread.h
OPEN_READER_NOSIZE
#define OPEN_READER_NOSIZE(name, gb)
Definition: get_bits.h:133
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:3105
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
GetBitContext
Definition: get_bits.h:61
IDCTDSPContext::idct_put
void(* idct_put)(uint8_t *dest, ptrdiff_t line_size, int16_t *block)
block -> idct -> clip to unsigned 8 bit -> dest.
Definition: idctdsp.h:72
ff_simple_idct248_put
void ff_simple_idct248_put(uint8_t *dest, ptrdiff_t line_size, int16_t *block)
Definition: simple_idct.c:106
dv_iweight_720_y
static const uint16_t dv_iweight_720_y[64]
Definition: dvdec.c:110
BlockInfo::partial_bit_buffer
uint32_t partial_bit_buffer
Definition: dvdec.c:60
ff_dv_rl_vlc
RL_VLC_ELEM ff_dv_rl_vlc[1664]
Definition: dv.c:52
dv_iweight_88
static const uint16_t dv_iweight_88[64]
Definition: dvdec.c:66
dv_iweight_1080_y
static const uint16_t dv_iweight_1080_y[64]
The "inverse" DV100 weights are actually just the spec weights (zig-zagged).
Definition: dvdec.c:90
avassert.h
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
ff_dv_init_dynamic_tables
int ff_dv_init_dynamic_tables(DVVideoContext *ctx, const AVDVProfile *d)
Definition: dv.c:175
buf
void * buf
Definition: avisynth_c.h:766
av_cold
#define av_cold
Definition: attributes.h:84
dv_decode_video_segment
static int dv_decode_video_segment(AVCodecContext *avctx, void *arg)
Definition: dvdec.c:276
dvvideo_decode_init
static av_cold int dvvideo_decode_init(AVCodecContext *avctx)
Definition: dvdec.c:177
CLOSE_READER
#define CLOSE_READER(name, gb)
Definition: get_bits.h:149
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
s
#define s(width, name)
Definition: cbs_vp9.c:257
dv_decode_ac
static void dv_decode_ac(GetBitContext *gb, BlockInfo *mb, int16_t *block)
Definition: dvdec.c:204
frame_size
int frame_size
Definition: mxfenc.c:2215
AVCodecContext::error_concealment
int error_concealment
error concealment flags
Definition: avcodec.h:2640
BlockInfo::factor_table
const uint32_t * factor_table
Definition: dvdec.c:55
get_sbits
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:359
ctx
AVFormatContext * ctx
Definition: movenc.c:48
get_bits.h
simple_idct.h
AV_PIX_FMT_YUV420P
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
PutBitContext
Definition: put_bits.h:35
arg
const char * arg
Definition: jacosubdec.c:66
dv_iweight_720_c
static const uint16_t dv_iweight_720_c[64]
Definition: dvdec.c:120
if
if(ret)
Definition: filter_design.txt:179
AV_CODEC_CAP_FRAME_THREADS
#define AV_CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: avcodec.h:1037
ff_dv_quant_shifts
const uint8_t ff_dv_quant_shifts[22][4]
Definition: dvdata.c:45
NULL
#define NULL
Definition: coverity.c:32
run
uint8_t run
Definition: svq3.c:206
idct_put
static void idct_put(FourXContext *f, int x, int y)
Definition: 4xm.c:556
BlockInfo::idct_put
void(* idct_put)(uint8_t *dest, ptrdiff_t stride, int16_t *block)
Definition: dvdec.c:58
DVVideoContext
Definition: dv.h:40
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
get_bits1
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
ff_thread_get_buffer
int ff_thread_get_buffer(AVCodecContext *avctx, ThreadFrame *f, int flags)
Wrapper around get_buffer() for frame-multithreaded codecs.
Definition: pthread_frame.c:964
index
int index
Definition: gxfenc.c:89
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
BlockInfo
Definition: dvdec.c:54
RL_VLC_ELEM::len
int8_t len
Definition: vlc.h:34
ff_dlog
#define ff_dlog(a,...)
Definition: tableprint_vlc.h:29
dv.h
AVCodecContext::lowres
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:2804
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981
AVPacket::size
int size
Definition: avcodec.h:1478
dc
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled top and top right vectors is used as motion vector prediction the used motion vector is the sum of the predictor and(mvx_diff, mvy_diff) *mv_scale Intra DC Prediction block[y][x] dc[1]
Definition: snow.txt:400
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:188
FFMAX
#define FFMAX(a, b)
Definition: common.h:94
ff_dv_zigzag248_direct
const uint8_t ff_dv_zigzag248_direct[64]
Definition: dvdata.c:33
AVDVProfile::height
int height
Definition: dv_profile.h:47
AV_CODEC_CAP_SLICE_THREADS
#define AV_CODEC_CAP_SLICE_THREADS
Codec supports slice-based (or partition-based) multithreading.
Definition: avcodec.h:1041
BlockInfo::shift_offset
int shift_offset
Definition: dvdec.c:61
DV_PROFILE_IS_HD
#define DV_PROFILE_IS_HD(p)
Definition: dv.h:82
mb
#define mb
Definition: vf_colormatrix.c:101
NEG_USR32
#define NEG_USR32(a, s)
Definition: mathops.h:166
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
put_bits_count
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:85
dv_iweight_248
static const uint16_t dv_iweight_248[64]
Definition: dvdec.c:76
internal.h
av_assert1
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
MIN_CACHE_BITS
#define MIN_CACHE_BITS
Definition: get_bits.h:128
TEX_VLC_BITS
#define TEX_VLC_BITS
Definition: dv.h:96
AV_CODEC_ID_DVVIDEO
@ AV_CODEC_ID_DVVIDEO
Definition: avcodec.h:242
dv_work_pool_size
static int dv_work_pool_size(const AVDVProfile *d)
Definition: dv.h:104
dv_video_control
@ dv_video_control
Definition: dv.h:76
uint8_t
uint8_t
Definition: audio_convert.c:194
ff_idctdsp_init
av_cold void ff_idctdsp_init(IDCTDSPContext *c, AVCodecContext *avctx)
Definition: idctdsp.c:238
AVCodec::name
const char * name
Name of the codec implementation.
Definition: avcodec.h:3488
av_inv_q
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
BlockInfo::scan_table
const uint8_t * scan_table
Definition: dvdec.c:56
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
idctdsp.h
avcodec.h
ff_zigzag_direct
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:98
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
dv_calculate_mb_xy
static void dv_calculate_mb_xy(DVVideoContext *s, DVwork_chunk *work_chunk, int m, int *mb_x, int *mb_y)
Definition: dv.h:114
IDCTDSPContext
Definition: idctdsp.h:53
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: avcodec.h:790
ff_set_sar
int ff_set_sar(AVCodecContext *avctx, AVRational sar)
Check that the provided sample aspect ratio is valid and set it on the codec context.
Definition: utils.c:119
AVCodecContext
main external API structure.
Definition: avcodec.h:1565
ThreadFrame
Definition: thread.h:34
ff_dv_quant_offset
const uint8_t ff_dv_quant_offset[4]
Definition: dvdata.c:70
AVCodecContext::execute
int(* execute)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size)
The codec may call this to execute several independent things.
Definition: avcodec.h:2864
SHOW_UBITS
#define SHOW_UBITS(name, gb, num)
Definition: get_bits.h:211
AVDVProfile
Definition: dv_profile.h:39
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
ff_dvvideo_decoder
AVCodec ff_dvvideo_decoder
Definition: dvdec.c:565
ff_set_dimensions
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:104
IDCTDSPContext::idct_permutation
uint8_t idct_permutation[64]
IDCT input permutation.
Definition: idctdsp.h:96
flush_put_bits
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:101
quant
const uint8_t * quant
Definition: vorbis_enc_data.h:458
ff_dvvideo_init
av_cold int ff_dvvideo_init(AVCodecContext *avctx)
Definition: dv.c:198
dv_iweight_1080_c
static const uint16_t dv_iweight_1080_c[64]
Definition: dvdec.c:100
LOCAL_ALIGNED_16
#define LOCAL_ALIGNED_16(t, v,...)
Definition: internal.h:131
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1454
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:1592
AV_PIX_FMT_YUV411P
@ AV_PIX_FMT_YUV411P
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:73
imgutils.h
block
The exact code depends on how similar the blocks are and how related they are to the block
Definition: filter_design.txt:207
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
dvvideo_decode_frame
static int dvvideo_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: dvdec.c:497
put_bits.h
dv_iweight_bits
static const int dv_iweight_bits
Definition: dvdec.c:64
block1
static int16_t block1[64]
Definition: dct.c:116
RL_VLC_ELEM::level
int16_t level
Definition: vlc.h:33
dvdata.h
BlockInfo::partial_bit_count
uint8_t partial_bit_count
Definition: dvdec.c:59
re
float re
Definition: fft.c:82
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