nutenc.c
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1 /*
2  * nut muxer
3  * Copyright (c) 2004-2007 Michael Niedermayer
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 
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/mathematics.h"
24 #include "libavutil/tree.h"
25 #include "libavutil/dict.h"
27 #include "nut.h"
28 #include "internal.h"
29 #include "avio_internal.h"
30 
31 static int find_expected_header(AVCodecContext *c, int size, int key_frame, uint8_t out[64]){
32  int sample_rate= c->sample_rate;
33 
34  if(size>4096)
35  return 0;
36 
37  AV_WB24(out, 1);
38 
39  if(c->codec_id == CODEC_ID_MPEG4){
40  if(key_frame){
41  return 3;
42  }else{
43  out[3]= 0xB6;
44  return 4;
45  }
47  return 3;
48  }else if(c->codec_id == CODEC_ID_H264){
49  return 3;
50  }else if(c->codec_id == CODEC_ID_MP3 || c->codec_id == CODEC_ID_MP2){
51  int lsf, mpeg25, sample_rate_index, bitrate_index, frame_size;
52  int layer= c->codec_id == CODEC_ID_MP3 ? 3 : 2;
53  unsigned int header= 0xFFF00000;
54 
55  lsf = sample_rate < (24000+32000)/2;
56  mpeg25 = sample_rate < (12000+16000)/2;
57  sample_rate <<= lsf + mpeg25;
58  if (sample_rate < (32000 + 44100)/2) sample_rate_index=2;
59  else if(sample_rate < (44100 + 48000)/2) sample_rate_index=0;
60  else sample_rate_index=1;
61 
62  sample_rate= avpriv_mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25);
63 
64  for(bitrate_index=2; bitrate_index<30; bitrate_index++){
65  frame_size = avpriv_mpa_bitrate_tab[lsf][layer-1][bitrate_index>>1];
66  frame_size = (frame_size * 144000) / (sample_rate << lsf) + (bitrate_index&1);
67 
68  if(frame_size == size)
69  break;
70  }
71 
72  header |= (!lsf)<<19;
73  header |= (4-layer)<<17;
74  header |= 1<<16; //no crc
75  AV_WB32(out, header);
76  if(size <= 0)
77  return 2; //we guess there is no crc, if there is one the user clearly does not care about overhead
78  if(bitrate_index == 30)
79  return -1; //something is wrong ...
80 
81  header |= (bitrate_index>>1)<<12;
82  header |= sample_rate_index<<10;
83  header |= (bitrate_index&1)<<9;
84 
85  return 2; //FIXME actually put the needed ones in build_elision_headers()
86  return 3; //we guess that the private bit is not set
87 //FIXME the above assumptions should be checked, if these turn out false too often something should be done
88  }
89  return 0;
90 }
91 
92 static int find_header_idx(AVFormatContext *s, AVCodecContext *c, int size, int frame_type){
93  NUTContext *nut = s->priv_data;
94  uint8_t out[64];
95  int i;
96  int len= find_expected_header(c, size, frame_type, out);
97 
98 //av_log(NULL, AV_LOG_ERROR, "expected_h len=%d size=%d codec_id=%d\n", len, size, c->codec_id);
99 
100  for(i=1; i<nut->header_count; i++){
101  if( len == nut->header_len[i]
102  && !memcmp(out, nut->header[i], len)){
103 // av_log(NULL, AV_LOG_ERROR, "found %d\n", i);
104  return i;
105  }
106  }
107 // av_log(NULL, AV_LOG_ERROR, "nothing found\n");
108  return 0;
109 }
110 
112  NUTContext *nut = s->priv_data;
113  int i;
114  //FIXME this is lame
115  //FIXME write a 2pass mode to find the maximal headers
116  static const uint8_t headers[][5]={
117  {3, 0x00, 0x00, 0x01},
118  {4, 0x00, 0x00, 0x01, 0xB6},
119  {2, 0xFF, 0xFA}, //mp3+crc
120  {2, 0xFF, 0xFB}, //mp3
121  {2, 0xFF, 0xFC}, //mp2+crc
122  {2, 0xFF, 0xFD}, //mp2
123  };
124 
125  nut->header_count= 7;
126  for(i=1; i<nut->header_count; i++){
127  nut->header_len[i]= headers[i-1][0];
128  nut->header [i]= &headers[i-1][1];
129  }
130 }
131 
133  NUTContext *nut = s->priv_data;
134  int key_frame, index, pred, stream_id;
135  int start=1;
136  int end= 254;
137  int keyframe_0_esc= s->nb_streams > 2;
138  int pred_table[10];
139  FrameCode *ft;
140 
141  ft= &nut->frame_code[start];
142  ft->flags= FLAG_CODED;
143  ft->size_mul=1;
144  ft->pts_delta=1;
145  start++;
146 
147  if(keyframe_0_esc){
148  /* keyframe = 0 escape */
149  FrameCode *ft= &nut->frame_code[start];
151  ft->size_mul=1;
152  start++;
153  }
154 
155  for(stream_id= 0; stream_id<s->nb_streams; stream_id++){
156  int start2= start + (end-start)*stream_id / s->nb_streams;
157  int end2 = start + (end-start)*(stream_id+1) / s->nb_streams;
158  AVCodecContext *codec = s->streams[stream_id]->codec;
159  int is_audio= codec->codec_type == AVMEDIA_TYPE_AUDIO;
160  int intra_only= /*codec->intra_only || */is_audio;
161  int pred_count;
162 
163  for(key_frame=0; key_frame<2; key_frame++){
164  if(intra_only && keyframe_0_esc && key_frame==0)
165  continue;
166 
167  {
168  FrameCode *ft= &nut->frame_code[start2];
169  ft->flags= FLAG_KEY*key_frame;
171  ft->stream_id= stream_id;
172  ft->size_mul=1;
173  if(is_audio)
174  ft->header_idx= find_header_idx(s, codec, -1, key_frame);
175  start2++;
176  }
177  }
178 
179  key_frame= intra_only;
180  if(is_audio){
181  int frame_bytes= codec->frame_size*(int64_t)codec->bit_rate / (8*codec->sample_rate);
182  int pts;
183  for(pts=0; pts<2; pts++){
184  for(pred=0; pred<2; pred++){
185  FrameCode *ft= &nut->frame_code[start2];
186  ft->flags= FLAG_KEY*key_frame;
187  ft->stream_id= stream_id;
188  ft->size_mul=frame_bytes + 2;
189  ft->size_lsb=frame_bytes + pred;
190  ft->pts_delta=pts;
191  ft->header_idx= find_header_idx(s, codec, frame_bytes + pred, key_frame);
192  start2++;
193  }
194  }
195  }else{
196  FrameCode *ft= &nut->frame_code[start2];
198  ft->stream_id= stream_id;
199  ft->size_mul=1;
200  ft->pts_delta=1;
201  start2++;
202  }
203 
204  if(codec->has_b_frames){
205  pred_count=5;
206  pred_table[0]=-2;
207  pred_table[1]=-1;
208  pred_table[2]=1;
209  pred_table[3]=3;
210  pred_table[4]=4;
211  }else if(codec->codec_id == CODEC_ID_VORBIS){
212  pred_count=3;
213  pred_table[0]=2;
214  pred_table[1]=9;
215  pred_table[2]=16;
216  }else{
217  pred_count=1;
218  pred_table[0]=1;
219  }
220 
221  for(pred=0; pred<pred_count; pred++){
222  int start3= start2 + (end2-start2)*pred / pred_count;
223  int end3 = start2 + (end2-start2)*(pred+1) / pred_count;
224 
225  for(index=start3; index<end3; index++){
226  FrameCode *ft= &nut->frame_code[index];
227  ft->flags= FLAG_KEY*key_frame;
228  ft->flags|= FLAG_SIZE_MSB;
229  ft->stream_id= stream_id;
230 //FIXME use single byte size and pred from last
231  ft->size_mul= end3-start3;
232  ft->size_lsb= index - start3;
233  ft->pts_delta= pred_table[pred];
234  if(is_audio)
235  ft->header_idx= find_header_idx(s, codec, -1, key_frame);
236  }
237  }
238  }
239  memmove(&nut->frame_code['N'+1], &nut->frame_code['N'], sizeof(FrameCode)*(255-'N'));
240  nut->frame_code[ 0].flags=
241  nut->frame_code[255].flags=
242  nut->frame_code['N'].flags= FLAG_INVALID;
243 }
244 
245 static void put_tt(NUTContext *nut, AVRational *time_base, AVIOContext *bc, uint64_t val){
246  val *= nut->time_base_count;
247  val += time_base - nut->time_base;
248  ff_put_v(bc, val);
249 }
250 
254 static void put_str(AVIOContext *bc, const char *string){
255  int len= strlen(string);
256 
257  ff_put_v(bc, len);
258  avio_write(bc, string, len);
259 }
260 
261 static void put_s(AVIOContext *bc, int64_t val){
262  ff_put_v(bc, 2*FFABS(val) - (val>0));
263 }
264 
265 #ifdef TRACE
266 static inline void ff_put_v_trace(AVIOContext *bc, uint64_t v, char *file, char *func, int line){
267  av_log(NULL, AV_LOG_DEBUG, "ff_put_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
268 
269  ff_put_v(bc, v);
270 }
271 
272 static inline void put_s_trace(AVIOContext *bc, int64_t v, char *file, char *func, int line){
273  av_log(NULL, AV_LOG_DEBUG, "put_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
274 
275  put_s(bc, v);
276 }
277 #define ff_put_v(bc, v) ff_put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
278 #define put_s(bc, v) put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
279 #endif
280 
281 //FIXME remove calculate_checksum
282 static void put_packet(NUTContext *nut, AVIOContext *bc, AVIOContext *dyn_bc, int calculate_checksum, uint64_t startcode){
283  uint8_t *dyn_buf=NULL;
284  int dyn_size= avio_close_dyn_buf(dyn_bc, &dyn_buf);
285  int forw_ptr= dyn_size + 4*calculate_checksum;
286 
287  if(forw_ptr > 4096)
289  avio_wb64(bc, startcode);
290  ff_put_v(bc, forw_ptr);
291  if(forw_ptr > 4096)
292  avio_wl32(bc, ffio_get_checksum(bc));
293 
294  if(calculate_checksum)
296  avio_write(bc, dyn_buf, dyn_size);
297  if(calculate_checksum)
298  avio_wl32(bc, ffio_get_checksum(bc));
299 
300  av_free(dyn_buf);
301 }
302 
303 static void write_mainheader(NUTContext *nut, AVIOContext *bc){
304  int i, j, tmp_pts, tmp_flags, tmp_stream, tmp_mul, tmp_size, tmp_fields, tmp_head_idx;
305  int64_t tmp_match;
306 
307  ff_put_v(bc, 3); /* version */
308  ff_put_v(bc, nut->avf->nb_streams);
309  ff_put_v(bc, nut->max_distance);
310  ff_put_v(bc, nut->time_base_count);
311 
312  for(i=0; i<nut->time_base_count; i++){
313  ff_put_v(bc, nut->time_base[i].num);
314  ff_put_v(bc, nut->time_base[i].den);
315  }
316 
317  tmp_pts=0;
318  tmp_mul=1;
319  tmp_stream=0;
320  tmp_match= 1-(1LL<<62);
321  tmp_head_idx= 0;
322  for(i=0; i<256;){
323  tmp_fields=0;
324  tmp_size=0;
325 // tmp_res=0;
326  if(tmp_pts != nut->frame_code[i].pts_delta) tmp_fields=1;
327  if(tmp_mul != nut->frame_code[i].size_mul ) tmp_fields=2;
328  if(tmp_stream != nut->frame_code[i].stream_id) tmp_fields=3;
329  if(tmp_size != nut->frame_code[i].size_lsb ) tmp_fields=4;
330 // if(tmp_res != nut->frame_code[i].res ) tmp_fields=5;
331  if(tmp_head_idx!=nut->frame_code[i].header_idx)tmp_fields=8;
332 
333  tmp_pts = nut->frame_code[i].pts_delta;
334  tmp_flags = nut->frame_code[i].flags;
335  tmp_stream= nut->frame_code[i].stream_id;
336  tmp_mul = nut->frame_code[i].size_mul;
337  tmp_size = nut->frame_code[i].size_lsb;
338 // tmp_res = nut->frame_code[i].res;
339  tmp_head_idx= nut->frame_code[i].header_idx;
340 
341  for(j=0; i<256; j++,i++){
342  if(i == 'N'){
343  j--;
344  continue;
345  }
346  if(nut->frame_code[i].pts_delta != tmp_pts ) break;
347  if(nut->frame_code[i].flags != tmp_flags ) break;
348  if(nut->frame_code[i].stream_id != tmp_stream) break;
349  if(nut->frame_code[i].size_mul != tmp_mul ) break;
350  if(nut->frame_code[i].size_lsb != tmp_size+j) break;
351 // if(nut->frame_code[i].res != tmp_res ) break;
352  if(nut->frame_code[i].header_idx!= tmp_head_idx) break;
353  }
354  if(j != tmp_mul - tmp_size) tmp_fields=6;
355 
356  ff_put_v(bc, tmp_flags);
357  ff_put_v(bc, tmp_fields);
358  if(tmp_fields>0) put_s(bc, tmp_pts);
359  if(tmp_fields>1) ff_put_v(bc, tmp_mul);
360  if(tmp_fields>2) ff_put_v(bc, tmp_stream);
361  if(tmp_fields>3) ff_put_v(bc, tmp_size);
362  if(tmp_fields>4) ff_put_v(bc, 0 /*tmp_res*/);
363  if(tmp_fields>5) ff_put_v(bc, j);
364  if(tmp_fields>6) ff_put_v(bc, tmp_match);
365  if(tmp_fields>7) ff_put_v(bc, tmp_head_idx);
366  }
367  ff_put_v(bc, nut->header_count-1);
368  for(i=1; i<nut->header_count; i++){
369  ff_put_v(bc, nut->header_len[i]);
370  avio_write(bc, nut->header[i], nut->header_len[i]);
371  }
372 }
373 
374 static int write_streamheader(AVFormatContext *avctx, AVIOContext *bc, AVStream *st, int i){
375  NUTContext *nut = avctx->priv_data;
376  AVCodecContext *codec = st->codec;
377  ff_put_v(bc, i);
378  switch(codec->codec_type){
379  case AVMEDIA_TYPE_VIDEO: ff_put_v(bc, 0); break;
380  case AVMEDIA_TYPE_AUDIO: ff_put_v(bc, 1); break;
381  case AVMEDIA_TYPE_SUBTITLE: ff_put_v(bc, 2); break;
382  default : ff_put_v(bc, 3); break;
383  }
384  ff_put_v(bc, 4);
385  if (codec->codec_tag){
386  avio_wl32(bc, codec->codec_tag);
387  } else {
388  av_log(avctx, AV_LOG_ERROR, "No codec tag defined for stream %d\n", i);
389  return AVERROR(EINVAL);
390  }
391 
392  ff_put_v(bc, nut->stream[i].time_base - nut->time_base);
393  ff_put_v(bc, nut->stream[i].msb_pts_shift);
394  ff_put_v(bc, nut->stream[i].max_pts_distance);
395  ff_put_v(bc, codec->has_b_frames);
396  avio_w8(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
397 
398  ff_put_v(bc, codec->extradata_size);
399  avio_write(bc, codec->extradata, codec->extradata_size);
400 
401  switch(codec->codec_type){
402  case AVMEDIA_TYPE_AUDIO:
403  ff_put_v(bc, codec->sample_rate);
404  ff_put_v(bc, 1);
405  ff_put_v(bc, codec->channels);
406  break;
407  case AVMEDIA_TYPE_VIDEO:
408  ff_put_v(bc, codec->width);
409  ff_put_v(bc, codec->height);
410 
411  if(st->sample_aspect_ratio.num<=0 || st->sample_aspect_ratio.den<=0){
412  ff_put_v(bc, 0);
413  ff_put_v(bc, 0);
414  }else{
417  }
418  ff_put_v(bc, 0); /* csp type -- unknown */
419  break;
420  default:
421  break;
422  }
423  return 0;
424 }
425 
426 static int add_info(AVIOContext *bc, const char *type, const char *value){
427  put_str(bc, type);
428  put_s(bc, -1);
429  put_str(bc, value);
430  return 1;
431 }
432 
434  AVFormatContext *s= nut->avf;
436  AVIOContext *dyn_bc;
437  uint8_t *dyn_buf=NULL;
438  int count=0, dyn_size;
439  int ret = avio_open_dyn_buf(&dyn_bc);
440  if(ret < 0)
441  return ret;
442 
443  while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))
444  count += add_info(dyn_bc, t->key, t->value);
445 
446  ff_put_v(bc, 0); //stream_if_plus1
447  ff_put_v(bc, 0); //chapter_id
448  ff_put_v(bc, 0); //timestamp_start
449  ff_put_v(bc, 0); //length
450 
451  ff_put_v(bc, count);
452 
453  dyn_size= avio_close_dyn_buf(dyn_bc, &dyn_buf);
454  avio_write(bc, dyn_buf, dyn_size);
455  av_free(dyn_buf);
456  return 0;
457 }
458 
459 static int write_streaminfo(NUTContext *nut, AVIOContext *bc, int stream_id){
460  AVFormatContext *s= nut->avf;
461  AVStream* st = s->streams[stream_id];
462  AVIOContext *dyn_bc;
463  uint8_t *dyn_buf=NULL;
464  int count=0, dyn_size, i;
465  int ret = avio_open_dyn_buf(&dyn_bc);
466  if(ret < 0)
467  return ret;
468 
469  for (i=0; ff_nut_dispositions[i].flag; ++i) {
470  if (st->disposition & ff_nut_dispositions[i].flag)
471  count += add_info(dyn_bc, "Disposition", ff_nut_dispositions[i].str);
472  }
473  dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
474 
475  if (count) {
476  ff_put_v(bc, stream_id + 1); //stream_id_plus1
477  ff_put_v(bc, 0); //chapter_id
478  ff_put_v(bc, 0); //timestamp_start
479  ff_put_v(bc, 0); //length
480 
481  ff_put_v(bc, count);
482 
483  avio_write(bc, dyn_buf, dyn_size);
484  }
485 
486  av_free(dyn_buf);
487  return count;
488 }
489 
490 static int write_chapter(NUTContext *nut, AVIOContext *bc, int id)
491 {
492  AVIOContext *dyn_bc;
493  uint8_t *dyn_buf = NULL;
495  AVChapter *ch = nut->avf->chapters[id];
496  int ret, dyn_size, count = 0;
497 
498  ret = avio_open_dyn_buf(&dyn_bc);
499  if (ret < 0)
500  return ret;
501 
502  ff_put_v(bc, 0); // stream_id_plus1
503  put_s(bc, id + 1); // chapter_id
504  put_tt(nut, nut->chapter[id].time_base, bc, ch->start); // chapter_start
505  ff_put_v(bc, ch->end - ch->start); // chapter_len
506 
507  while ((t = av_dict_get(ch->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))
508  count += add_info(dyn_bc, t->key, t->value);
509 
510  ff_put_v(bc, count);
511 
512  dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
513  avio_write(bc, dyn_buf, dyn_size);
514  av_freep(&dyn_buf);
515  return 0;
516 }
517 
518 static int write_headers(AVFormatContext *avctx, AVIOContext *bc){
519  NUTContext *nut = avctx->priv_data;
520  AVIOContext *dyn_bc;
521  int i, ret;
522 
524 
525  ret = avio_open_dyn_buf(&dyn_bc);
526  if(ret < 0)
527  return ret;
528  write_mainheader(nut, dyn_bc);
529  put_packet(nut, bc, dyn_bc, 1, MAIN_STARTCODE);
530 
531  for (i=0; i < nut->avf->nb_streams; i++){
532  ret = avio_open_dyn_buf(&dyn_bc);
533  if(ret < 0)
534  return ret;
535  if ((ret = write_streamheader(avctx, dyn_bc, nut->avf->streams[i], i)) < 0)
536  return ret;
537  put_packet(nut, bc, dyn_bc, 1, STREAM_STARTCODE);
538  }
539 
540  ret = avio_open_dyn_buf(&dyn_bc);
541  if(ret < 0)
542  return ret;
543  write_globalinfo(nut, dyn_bc);
544  put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
545 
546  for (i = 0; i < nut->avf->nb_streams; i++) {
547  ret = avio_open_dyn_buf(&dyn_bc);
548  if(ret < 0)
549  return ret;
550  ret = write_streaminfo(nut, dyn_bc, i);
551  if (ret < 0)
552  return ret;
553  if (ret > 0)
554  put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
555  else {
556  uint8_t* buf;
557  avio_close_dyn_buf(dyn_bc, &buf);
558  av_free(buf);
559  }
560  }
561 
562  for (i = 0; i < nut->avf->nb_chapters; i++) {
563  ret = avio_open_dyn_buf(&dyn_bc);
564  if (ret < 0)
565  return ret;
566  ret = write_chapter(nut, dyn_bc, i);
567  if (ret < 0) {
568  uint8_t *buf;
569  avio_close_dyn_buf(dyn_bc, &buf);
570  av_freep(&buf);
571  return ret;
572  }
573  put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
574  }
575 
576  nut->last_syncpoint_pos= INT_MIN;
577  nut->header_count++;
578  return 0;
579 }
580 
582  NUTContext *nut = s->priv_data;
583  AVIOContext *bc = s->pb;
584  int i, j, ret;
585 
586  nut->avf= s;
587 
588  nut->stream = av_mallocz(sizeof(StreamContext)*s->nb_streams);
589  if (s->nb_chapters)
590  nut->chapter = av_mallocz(sizeof(ChapterContext)*s->nb_chapters);
591  nut->time_base= av_mallocz(sizeof(AVRational )*(s->nb_streams +
592  s->nb_chapters));
593  if (!nut->stream || (s->nb_chapters && !nut->chapter) || !nut->time_base) {
594  av_freep(&nut->stream);
595  av_freep(&nut->chapter);
596  av_freep(&nut->time_base);
597  return AVERROR(ENOMEM);
598  }
599 
600  for(i=0; i<s->nb_streams; i++){
601  AVStream *st= s->streams[i];
602  int ssize;
603  AVRational time_base;
604  ff_parse_specific_params(st->codec, &time_base.den, &ssize, &time_base.num);
605 
606  avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
607 
608  for(j=0; j<nut->time_base_count; j++){
609  if(!memcmp(&time_base, &nut->time_base[j], sizeof(AVRational))){
610  break;
611  }
612  }
613  nut->time_base[j]= time_base;
614  nut->stream[i].time_base= &nut->time_base[j];
615  if(j==nut->time_base_count)
616  nut->time_base_count++;
617 
618  if(INT64_C(1000) * time_base.num >= time_base.den)
619  nut->stream[i].msb_pts_shift = 7;
620  else
621  nut->stream[i].msb_pts_shift = 14;
622  nut->stream[i].max_pts_distance= FFMAX(time_base.den, time_base.num) / time_base.num;
623  }
624 
625  for (i = 0; i < s->nb_chapters; i++) {
626  AVChapter *ch = s->chapters[i];
627 
628  for (j = 0; j < nut->time_base_count; j++) {
629  if (!memcmp(&ch->time_base, &nut->time_base[j], sizeof(AVRational)))
630  break;
631  }
632 
633  nut->time_base[j] = ch->time_base;
634  nut->chapter[i].time_base = &nut->time_base[j];
635  if(j == nut->time_base_count)
636  nut->time_base_count++;
637  }
638 
639  nut->max_distance = MAX_DISTANCE;
641  build_frame_code(s);
642  assert(nut->frame_code['N'].flags == FLAG_INVALID);
643 
644  avio_write(bc, ID_STRING, strlen(ID_STRING));
645  avio_w8(bc, 0);
646 
647  if ((ret = write_headers(s, bc)) < 0)
648  return ret;
649 
650  avio_flush(bc);
651 
652  //FIXME index
653 
654  return 0;
655 }
656 
657 static int get_needed_flags(NUTContext *nut, StreamContext *nus, FrameCode *fc, AVPacket *pkt){
658  int flags= 0;
659 
660  if(pkt->flags & AV_PKT_FLAG_KEY ) flags |= FLAG_KEY;
661  if(pkt->stream_index != fc->stream_id ) flags |= FLAG_STREAM_ID;
662  if(pkt->size / fc->size_mul ) flags |= FLAG_SIZE_MSB;
663  if(pkt->pts - nus->last_pts != fc->pts_delta) flags |= FLAG_CODED_PTS;
664  if(pkt->size > 2*nut->max_distance ) flags |= FLAG_CHECKSUM;
665  if(FFABS(pkt->pts - nus->last_pts)
666  > nus->max_pts_distance) flags |= FLAG_CHECKSUM;
667  if( pkt->size < nut->header_len[fc->header_idx]
668  || (pkt->size > 4096 && fc->header_idx)
669  || memcmp(pkt->data, nut->header[fc->header_idx], nut->header_len[fc->header_idx]))
670  flags |= FLAG_HEADER_IDX;
671 
672  return flags | (fc->flags & FLAG_CODED);
673 }
674 
675 static int find_best_header_idx(NUTContext *nut, AVPacket *pkt){
676  int i;
677  int best_i = 0;
678  int best_len= 0;
679 
680  if(pkt->size > 4096)
681  return 0;
682 
683  for(i=1; i<nut->header_count; i++){
684  if( pkt->size >= nut->header_len[i]
685  && nut->header_len[i] > best_len
686  && !memcmp(pkt->data, nut->header[i], nut->header_len[i])){
687  best_i= i;
688  best_len= nut->header_len[i];
689  }
690  }
691  return best_i;
692 }
693 
695  NUTContext *nut = s->priv_data;
696  StreamContext *nus= &nut->stream[pkt->stream_index];
697  AVIOContext *bc = s->pb, *dyn_bc;
698  FrameCode *fc;
699  int64_t coded_pts;
700  int best_length, frame_code, flags, needed_flags, i, header_idx, best_header_idx;
701  int key_frame = !!(pkt->flags & AV_PKT_FLAG_KEY);
702  int store_sp=0;
703  int ret;
704 
705  if(pkt->pts < 0)
706  return -1;
707 
708  if(1LL<<(20+3*nut->header_count) <= avio_tell(bc))
709  write_headers(s, bc);
710 
711  if(key_frame && !(nus->last_flags & FLAG_KEY))
712  store_sp= 1;
713 
714  if(pkt->size + 30/*FIXME check*/ + avio_tell(bc) >= nut->last_syncpoint_pos + nut->max_distance)
715  store_sp= 1;
716 
717 //FIXME: Ensure store_sp is 1 in the first place.
718 
719  if(store_sp){
720  Syncpoint *sp, dummy= {.pos= INT64_MAX};
721 
722  ff_nut_reset_ts(nut, *nus->time_base, pkt->dts);
723  for(i=0; i<s->nb_streams; i++){
724  AVStream *st= s->streams[i];
725  int64_t dts_tb = av_rescale_rnd(pkt->dts,
726  nus->time_base->num * (int64_t)nut->stream[i].time_base->den,
727  nus->time_base->den * (int64_t)nut->stream[i].time_base->num,
728  AV_ROUND_DOWN);
730  if(index>=0) dummy.pos= FFMIN(dummy.pos, st->index_entries[index].pos);
731  }
732  if(dummy.pos == INT64_MAX)
733  dummy.pos= 0;
734  sp= av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
735  NULL);
736 
737  nut->last_syncpoint_pos= avio_tell(bc);
738  ret = avio_open_dyn_buf(&dyn_bc);
739  if(ret < 0)
740  return ret;
741  put_tt(nut, nus->time_base, dyn_bc, pkt->dts);
742  ff_put_v(dyn_bc, sp ? (nut->last_syncpoint_pos - sp->pos)>>4 : 0);
743  put_packet(nut, bc, dyn_bc, 1, SYNCPOINT_STARTCODE);
744 
745  ff_nut_add_sp(nut, nut->last_syncpoint_pos, 0/*unused*/, pkt->dts);
746  }
747  assert(nus->last_pts != AV_NOPTS_VALUE);
748 
749  coded_pts = pkt->pts & ((1<<nus->msb_pts_shift)-1);
750  if(ff_lsb2full(nus, coded_pts) != pkt->pts)
751  coded_pts= pkt->pts + (1<<nus->msb_pts_shift);
752 
753  best_header_idx= find_best_header_idx(nut, pkt);
754 
755  best_length=INT_MAX;
756  frame_code= -1;
757  for(i=0; i<256; i++){
758  int length= 0;
759  FrameCode *fc= &nut->frame_code[i];
760  int flags= fc->flags;
761 
762  if(flags & FLAG_INVALID)
763  continue;
764  needed_flags= get_needed_flags(nut, nus, fc, pkt);
765 
766  if(flags & FLAG_CODED){
767  length++;
768  flags = needed_flags;
769  }
770 
771  if((flags & needed_flags) != needed_flags)
772  continue;
773 
774  if((flags ^ needed_flags) & FLAG_KEY)
775  continue;
776 
777  if(flags & FLAG_STREAM_ID)
778  length+= ff_get_v_length(pkt->stream_index);
779 
780  if(pkt->size % fc->size_mul != fc->size_lsb)
781  continue;
782  if(flags & FLAG_SIZE_MSB)
783  length += ff_get_v_length(pkt->size / fc->size_mul);
784 
785  if(flags & FLAG_CHECKSUM)
786  length+=4;
787 
788  if(flags & FLAG_CODED_PTS)
789  length += ff_get_v_length(coded_pts);
790 
791  if( (flags & FLAG_CODED)
792  && nut->header_len[best_header_idx] > nut->header_len[fc->header_idx]+1){
793  flags |= FLAG_HEADER_IDX;
794  }
795 
796  if(flags & FLAG_HEADER_IDX){
797  length += 1 - nut->header_len[best_header_idx];
798  }else{
799  length -= nut->header_len[fc->header_idx];
800  }
801 
802  length*=4;
803  length+= !(flags & FLAG_CODED_PTS);
804  length+= !(flags & FLAG_CHECKSUM);
805 
806  if(length < best_length){
807  best_length= length;
808  frame_code=i;
809  }
810  }
811  assert(frame_code != -1);
812  fc= &nut->frame_code[frame_code];
813  flags= fc->flags;
814  needed_flags= get_needed_flags(nut, nus, fc, pkt);
815  header_idx= fc->header_idx;
816 
818  avio_w8(bc, frame_code);
819  if(flags & FLAG_CODED){
820  ff_put_v(bc, (flags^needed_flags) & ~(FLAG_CODED));
821  flags = needed_flags;
822  }
823  if(flags & FLAG_STREAM_ID) ff_put_v(bc, pkt->stream_index);
824  if(flags & FLAG_CODED_PTS) ff_put_v(bc, coded_pts);
825  if(flags & FLAG_SIZE_MSB) ff_put_v(bc, pkt->size / fc->size_mul);
826  if(flags & FLAG_HEADER_IDX) ff_put_v(bc, header_idx= best_header_idx);
827 
828  if(flags & FLAG_CHECKSUM) avio_wl32(bc, ffio_get_checksum(bc));
829  else ffio_get_checksum(bc);
830 
831  avio_write(bc, pkt->data + nut->header_len[header_idx], pkt->size - nut->header_len[header_idx]);
832  nus->last_flags= flags;
833  nus->last_pts= pkt->pts;
834 
835  //FIXME just store one per syncpoint
836  if(flags & FLAG_KEY)
838  s->streams[pkt->stream_index],
839  nut->last_syncpoint_pos,
840  pkt->pts,
841  0,
842  0,
844 
845  return 0;
846 }
847 
849  NUTContext *nut= s->priv_data;
850  AVIOContext *bc= s->pb;
851 
852  while(nut->header_count<3)
853  write_headers(s, bc);
854  avio_flush(bc);
855  ff_nut_free_sp(nut);
856  av_freep(&nut->stream);
857  av_freep(&nut->chapter);
858  av_freep(&nut->time_base);
859 
860  return 0;
861 }
862 
864  .name = "nut",
865  .long_name = NULL_IF_CONFIG_SMALL("NUT format"),
866  .mime_type = "video/x-nut",
867  .extensions = "nut",
868  .priv_data_size = sizeof(NUTContext),
870  .audio_codec = CODEC_ID_VORBIS,
871 #elif CONFIG_LIBMP3LAME
872  .audio_codec = CODEC_ID_MP3,
873 #else
874  .audio_codec = CODEC_ID_MP2,
875 #endif
876  .video_codec = CODEC_ID_MPEG4,
882 };