Make the nut decoder read the ff_nut_video_tags to detect codec id of
[libav.git] / libavformat / nutdec.c
1 /*
2 * "NUT" Container Format demuxer
3 * Copyright (c) 2004-2006 Michael Niedermayer
4 * Copyright (c) 2003 Alex Beregszaszi
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 #include <strings.h>
24 #include "libavutil/avstring.h"
25 #include "libavutil/bswap.h"
26 #include "libavutil/tree.h"
27 #include "nut.h"
28
29 #undef NDEBUG
30 #include <assert.h>
31
32 static int get_str(ByteIOContext *bc, char *string, unsigned int maxlen){
33 unsigned int len= ff_get_v(bc);
34
35 if(len && maxlen)
36 get_buffer(bc, string, FFMIN(len, maxlen));
37 while(len > maxlen){
38 get_byte(bc);
39 len--;
40 }
41
42 if(maxlen)
43 string[FFMIN(len, maxlen-1)]= 0;
44
45 if(maxlen == len)
46 return -1;
47 else
48 return 0;
49 }
50
51 static int64_t get_s(ByteIOContext *bc){
52 int64_t v = ff_get_v(bc) + 1;
53
54 if (v&1) return -(v>>1);
55 else return (v>>1);
56 }
57
58 static uint64_t get_fourcc(ByteIOContext *bc){
59 unsigned int len= ff_get_v(bc);
60
61 if (len==2) return get_le16(bc);
62 else if(len==4) return get_le32(bc);
63 else return -1;
64 }
65
66 #ifdef TRACE
67 static inline uint64_t get_v_trace(ByteIOContext *bc, char *file, char *func, int line){
68 uint64_t v= ff_get_v(bc);
69
70 av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
71 return v;
72 }
73
74 static inline int64_t get_s_trace(ByteIOContext *bc, char *file, char *func, int line){
75 int64_t v= get_s(bc);
76
77 av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
78 return v;
79 }
80
81 static inline uint64_t get_vb_trace(ByteIOContext *bc, char *file, char *func, int line){
82 uint64_t v= get_vb(bc);
83
84 av_log(NULL, AV_LOG_DEBUG, "get_vb %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
85 return v;
86 }
87 #define ff_get_v(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
88 #define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
89 #define get_vb(bc) get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
90 #endif
91
92 static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int calculate_checksum, uint64_t startcode)
93 {
94 int64_t size;
95 // start= url_ftell(bc) - 8;
96
97 startcode= be2me_64(startcode);
98 startcode= ff_crc04C11DB7_update(0, &startcode, 8);
99
100 init_checksum(bc, ff_crc04C11DB7_update, startcode);
101 size= ff_get_v(bc);
102 if(size > 4096)
103 get_be32(bc);
104 if(get_checksum(bc) && size > 4096)
105 return -1;
106
107 init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
108
109 return size;
110 }
111
112 static uint64_t find_any_startcode(ByteIOContext *bc, int64_t pos){
113 uint64_t state=0;
114
115 if(pos >= 0)
116 url_fseek(bc, pos, SEEK_SET); //note, this may fail if the stream is not seekable, but that should not matter, as in this case we simply start where we currently are
117
118 while(!url_feof(bc)){
119 state= (state<<8) | get_byte(bc);
120 if((state>>56) != 'N')
121 continue;
122 switch(state){
123 case MAIN_STARTCODE:
124 case STREAM_STARTCODE:
125 case SYNCPOINT_STARTCODE:
126 case INFO_STARTCODE:
127 case INDEX_STARTCODE:
128 return state;
129 }
130 }
131
132 return 0;
133 }
134
135 /**
136 * Find the given startcode.
137 * @param code the startcode
138 * @param pos the start position of the search, or -1 if the current position
139 * @return the position of the startcode or -1 if not found
140 */
141 static int64_t find_startcode(ByteIOContext *bc, uint64_t code, int64_t pos){
142 for(;;){
143 uint64_t startcode= find_any_startcode(bc, pos);
144 if(startcode == code)
145 return url_ftell(bc) - 8;
146 else if(startcode == 0)
147 return -1;
148 pos=-1;
149 }
150 }
151
152 static int nut_probe(AVProbeData *p){
153 int i;
154 uint64_t code= 0;
155
156 for (i = 0; i < p->buf_size; i++) {
157 code = (code << 8) | p->buf[i];
158 if (code == MAIN_STARTCODE)
159 return AVPROBE_SCORE_MAX;
160 }
161 return 0;
162 }
163
164 #define GET_V(dst, check) \
165 tmp= ff_get_v(bc);\
166 if(!(check)){\
167 av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp);\
168 return -1;\
169 }\
170 dst= tmp;
171
172 static int skip_reserved(ByteIOContext *bc, int64_t pos){
173 pos -= url_ftell(bc);
174 if(pos<0){
175 url_fseek(bc, pos, SEEK_CUR);
176 return -1;
177 }else{
178 while(pos--)
179 get_byte(bc);
180 return 0;
181 }
182 }
183
184 static int decode_main_header(NUTContext *nut){
185 AVFormatContext *s= nut->avf;
186 ByteIOContext *bc = s->pb;
187 uint64_t tmp, end;
188 unsigned int stream_count;
189 int i, j, tmp_stream, tmp_mul, tmp_pts, tmp_size, count, tmp_res, tmp_head_idx;
190 int64_t tmp_match;
191
192 end= get_packetheader(nut, bc, 1, MAIN_STARTCODE);
193 end += url_ftell(bc);
194
195 GET_V(tmp , tmp >=2 && tmp <= 3)
196 GET_V(stream_count , tmp > 0 && tmp <=MAX_STREAMS)
197
198 nut->max_distance = ff_get_v(bc);
199 if(nut->max_distance > 65536){
200 av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
201 nut->max_distance= 65536;
202 }
203
204 GET_V(nut->time_base_count, tmp>0 && tmp<INT_MAX / sizeof(AVRational))
205 nut->time_base= av_malloc(nut->time_base_count * sizeof(AVRational));
206
207 for(i=0; i<nut->time_base_count; i++){
208 GET_V(nut->time_base[i].num, tmp>0 && tmp<(1ULL<<31))
209 GET_V(nut->time_base[i].den, tmp>0 && tmp<(1ULL<<31))
210 if(av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1){
211 av_log(s, AV_LOG_ERROR, "time base invalid\n");
212 return -1;
213 }
214 }
215 tmp_pts=0;
216 tmp_mul=1;
217 tmp_stream=0;
218 tmp_match= 1-(1LL<<62);
219 tmp_head_idx= 0;
220 for(i=0; i<256;){
221 int tmp_flags = ff_get_v(bc);
222 int tmp_fields= ff_get_v(bc);
223 if(tmp_fields>0) tmp_pts = get_s(bc);
224 if(tmp_fields>1) tmp_mul = ff_get_v(bc);
225 if(tmp_fields>2) tmp_stream= ff_get_v(bc);
226 if(tmp_fields>3) tmp_size = ff_get_v(bc);
227 else tmp_size = 0;
228 if(tmp_fields>4) tmp_res = ff_get_v(bc);
229 else tmp_res = 0;
230 if(tmp_fields>5) count = ff_get_v(bc);
231 else count = tmp_mul - tmp_size;
232 if(tmp_fields>6) tmp_match = get_s(bc);
233 if(tmp_fields>7) tmp_head_idx= ff_get_v(bc);
234
235 while(tmp_fields-- > 8)
236 ff_get_v(bc);
237
238 if(count == 0 || i+count > 256){
239 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
240 return -1;
241 }
242 if(tmp_stream >= stream_count){
243 av_log(s, AV_LOG_ERROR, "illegal stream number\n");
244 return -1;
245 }
246
247 for(j=0; j<count; j++,i++){
248 if (i == 'N') {
249 nut->frame_code[i].flags= FLAG_INVALID;
250 j--;
251 continue;
252 }
253 nut->frame_code[i].flags = tmp_flags ;
254 nut->frame_code[i].pts_delta = tmp_pts ;
255 nut->frame_code[i].stream_id = tmp_stream;
256 nut->frame_code[i].size_mul = tmp_mul ;
257 nut->frame_code[i].size_lsb = tmp_size+j;
258 nut->frame_code[i].reserved_count = tmp_res ;
259 nut->frame_code[i].header_idx = tmp_head_idx;
260 }
261 }
262 assert(nut->frame_code['N'].flags == FLAG_INVALID);
263
264 if(end > url_ftell(bc) + 4){
265 int rem= 1024;
266 GET_V(nut->header_count, tmp<128U)
267 nut->header_count++;
268 for(i=1; i<nut->header_count; i++){
269 GET_V(nut->header_len[i], tmp>0 && tmp<256);
270 rem -= nut->header_len[i];
271 if(rem < 0){
272 av_log(s, AV_LOG_ERROR, "invalid elision header\n");
273 return -1;
274 }
275 nut->header[i]= av_malloc(nut->header_len[i]);
276 get_buffer(bc, nut->header[i], nut->header_len[i]);
277 }
278 assert(nut->header_len[0]==0);
279 }
280
281 if(skip_reserved(bc, end) || get_checksum(bc)){
282 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
283 return -1;
284 }
285
286 nut->stream = av_mallocz(sizeof(StreamContext)*stream_count);
287 for(i=0; i<stream_count; i++){
288 av_new_stream(s, i);
289 }
290
291 return 0;
292 }
293
294 static int decode_stream_header(NUTContext *nut){
295 AVFormatContext *s= nut->avf;
296 ByteIOContext *bc = s->pb;
297 StreamContext *stc;
298 int class, stream_id;
299 uint64_t tmp, end;
300 AVStream *st;
301
302 end= get_packetheader(nut, bc, 1, STREAM_STARTCODE);
303 end += url_ftell(bc);
304
305 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
306 stc= &nut->stream[stream_id];
307
308 st = s->streams[stream_id];
309 if (!st)
310 return AVERROR(ENOMEM);
311
312 class = ff_get_v(bc);
313 tmp = get_fourcc(bc);
314 st->codec->codec_tag= tmp;
315 switch(class)
316 {
317 case 0:
318 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
319 st->codec->codec_id = av_codec_get_id(
320 (const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, 0 },
321 tmp);
322 break;
323 case 1:
324 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
325 st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, tmp);
326 break;
327 case 2:
328 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
329 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
330 break;
331 case 3:
332 st->codec->codec_type = AVMEDIA_TYPE_DATA;
333 break;
334 default:
335 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
336 return -1;
337 }
338 if(class<3 && st->codec->codec_id == CODEC_ID_NONE)
339 av_log(s, AV_LOG_ERROR, "Unknown codec tag '0x%04x' for stream number %d\n",
340 (unsigned int)tmp, stream_id);
341
342 GET_V(stc->time_base_id , tmp < nut->time_base_count);
343 GET_V(stc->msb_pts_shift , tmp < 16);
344 stc->max_pts_distance= ff_get_v(bc);
345 GET_V(stc->decode_delay , tmp < 1000); //sanity limit, raise this if Moore's law is true
346 st->codec->has_b_frames= stc->decode_delay;
347 ff_get_v(bc); //stream flags
348
349 GET_V(st->codec->extradata_size, tmp < (1<<30));
350 if(st->codec->extradata_size){
351 st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
352 get_buffer(bc, st->codec->extradata, st->codec->extradata_size);
353 }
354
355 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO){
356 GET_V(st->codec->width , tmp > 0)
357 GET_V(st->codec->height, tmp > 0)
358 st->sample_aspect_ratio.num= ff_get_v(bc);
359 st->sample_aspect_ratio.den= ff_get_v(bc);
360 if((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)){
361 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
362 return -1;
363 }
364 ff_get_v(bc); /* csp type */
365 }else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO){
366 GET_V(st->codec->sample_rate , tmp > 0)
367 ff_get_v(bc); // samplerate_den
368 GET_V(st->codec->channels, tmp > 0)
369 }
370 if(skip_reserved(bc, end) || get_checksum(bc)){
371 av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id);
372 return -1;
373 }
374 stc->time_base= &nut->time_base[stc->time_base_id];
375 av_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den);
376 return 0;
377 }
378
379 static void set_disposition_bits(AVFormatContext* avf, char* value, int stream_id){
380 int flag = 0, i;
381 for (i=0; ff_nut_dispositions[i].flag; ++i) {
382 if (!strcmp(ff_nut_dispositions[i].str, value))
383 flag = ff_nut_dispositions[i].flag;
384 }
385 if (!flag)
386 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
387 for (i = 0; i < avf->nb_streams; ++i)
388 if (stream_id == i || stream_id == -1)
389 avf->streams[i]->disposition |= flag;
390 }
391
392 static int decode_info_header(NUTContext *nut){
393 AVFormatContext *s= nut->avf;
394 ByteIOContext *bc = s->pb;
395 uint64_t tmp, chapter_start, chapter_len;
396 unsigned int stream_id_plus1, count;
397 int chapter_id, i;
398 int64_t value, end;
399 char name[256], str_value[1024], type_str[256];
400 const char *type;
401 AVChapter *chapter= NULL;
402 AVStream *st= NULL;
403
404 end= get_packetheader(nut, bc, 1, INFO_STARTCODE);
405 end += url_ftell(bc);
406
407 GET_V(stream_id_plus1, tmp <= s->nb_streams)
408 chapter_id = get_s(bc);
409 chapter_start= ff_get_v(bc);
410 chapter_len = ff_get_v(bc);
411 count = ff_get_v(bc);
412
413 if(chapter_id && !stream_id_plus1){
414 int64_t start= chapter_start / nut->time_base_count;
415 chapter= ff_new_chapter(s, chapter_id,
416 nut->time_base[chapter_start % nut->time_base_count],
417 start, start + chapter_len, NULL);
418 } else if(stream_id_plus1)
419 st= s->streams[stream_id_plus1 - 1];
420
421 for(i=0; i<count; i++){
422 get_str(bc, name, sizeof(name));
423 value= get_s(bc);
424 if(value == -1){
425 type= "UTF-8";
426 get_str(bc, str_value, sizeof(str_value));
427 }else if(value == -2){
428 get_str(bc, type_str, sizeof(type_str));
429 type= type_str;
430 get_str(bc, str_value, sizeof(str_value));
431 }else if(value == -3){
432 type= "s";
433 value= get_s(bc);
434 }else if(value == -4){
435 type= "t";
436 value= ff_get_v(bc);
437 }else if(value < -4){
438 type= "r";
439 get_s(bc);
440 }else{
441 type= "v";
442 }
443
444 if (stream_id_plus1 > s->nb_streams) {
445 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
446 continue;
447 }
448
449 if(!strcmp(type, "UTF-8")){
450 AVMetadata **metadata = NULL;
451 if(chapter_id==0 && !strcmp(name, "Disposition"))
452 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
453 else if(chapter) metadata= &chapter->metadata;
454 else if(stream_id_plus1) metadata= &st->metadata;
455 else metadata= &s->metadata;
456 if(metadata && strcasecmp(name,"Uses")
457 && strcasecmp(name,"Depends") && strcasecmp(name,"Replaces"))
458 av_metadata_set2(metadata, name, str_value, 0);
459 }
460 }
461
462 if(skip_reserved(bc, end) || get_checksum(bc)){
463 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
464 return -1;
465 }
466 return 0;
467 }
468
469 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){
470 AVFormatContext *s= nut->avf;
471 ByteIOContext *bc = s->pb;
472 int64_t end, tmp;
473
474 nut->last_syncpoint_pos= url_ftell(bc)-8;
475
476 end= get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
477 end += url_ftell(bc);
478
479 tmp= ff_get_v(bc);
480 *back_ptr= nut->last_syncpoint_pos - 16*ff_get_v(bc);
481 if(*back_ptr < 0)
482 return -1;
483
484 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count);
485
486 if(skip_reserved(bc, end) || get_checksum(bc)){
487 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
488 return -1;
489 }
490
491 *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE;
492 ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
493
494 return 0;
495 }
496
497 static int find_and_decode_index(NUTContext *nut){
498 AVFormatContext *s= nut->avf;
499 ByteIOContext *bc = s->pb;
500 uint64_t tmp, end;
501 int i, j, syncpoint_count;
502 int64_t filesize= url_fsize(bc);
503 int64_t *syncpoints;
504 int8_t *has_keyframe;
505 int ret= -1;
506
507 url_fseek(bc, filesize-12, SEEK_SET);
508 url_fseek(bc, filesize-get_be64(bc), SEEK_SET);
509 if(get_be64(bc) != INDEX_STARTCODE){
510 av_log(s, AV_LOG_ERROR, "no index at the end\n");
511 return -1;
512 }
513
514 end= get_packetheader(nut, bc, 1, INDEX_STARTCODE);
515 end += url_ftell(bc);
516
517 ff_get_v(bc); //max_pts
518 GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0)
519 syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count);
520 has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1));
521 for(i=0; i<syncpoint_count; i++){
522 syncpoints[i] = ff_get_v(bc);
523 if(syncpoints[i] <= 0)
524 goto fail;
525 if(i)
526 syncpoints[i] += syncpoints[i-1];
527 }
528
529 for(i=0; i<s->nb_streams; i++){
530 int64_t last_pts= -1;
531 for(j=0; j<syncpoint_count;){
532 uint64_t x= ff_get_v(bc);
533 int type= x&1;
534 int n= j;
535 x>>=1;
536 if(type){
537 int flag= x&1;
538 x>>=1;
539 if(n+x >= syncpoint_count + 1){
540 av_log(s, AV_LOG_ERROR, "index overflow A\n");
541 goto fail;
542 }
543 while(x--)
544 has_keyframe[n++]= flag;
545 has_keyframe[n++]= !flag;
546 }else{
547 while(x != 1){
548 if(n>=syncpoint_count + 1){
549 av_log(s, AV_LOG_ERROR, "index overflow B\n");
550 goto fail;
551 }
552 has_keyframe[n++]= x&1;
553 x>>=1;
554 }
555 }
556 if(has_keyframe[0]){
557 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
558 goto fail;
559 }
560 assert(n<=syncpoint_count+1);
561 for(; j<n && j<syncpoint_count; j++){
562 if(has_keyframe[j]){
563 uint64_t B, A= ff_get_v(bc);
564 if(!A){
565 A= ff_get_v(bc);
566 B= ff_get_v(bc);
567 //eor_pts[j][i] = last_pts + A + B
568 }else
569 B= 0;
570 av_add_index_entry(
571 s->streams[i],
572 16*syncpoints[j-1],
573 last_pts + A,
574 0,
575 0,
576 AVINDEX_KEYFRAME);
577 last_pts += A + B;
578 }
579 }
580 }
581 }
582
583 if(skip_reserved(bc, end) || get_checksum(bc)){
584 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
585 goto fail;
586 }
587 ret= 0;
588 fail:
589 av_free(syncpoints);
590 av_free(has_keyframe);
591 return ret;
592 }
593
594 static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
595 {
596 NUTContext *nut = s->priv_data;
597 ByteIOContext *bc = s->pb;
598 int64_t pos;
599 int initialized_stream_count;
600
601 nut->avf= s;
602
603 /* main header */
604 pos=0;
605 do{
606 pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
607 if (pos<0+1){
608 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
609 return -1;
610 }
611 }while(decode_main_header(nut) < 0);
612
613 /* stream headers */
614 pos=0;
615 for(initialized_stream_count=0; initialized_stream_count < s->nb_streams;){
616 pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
617 if (pos<0+1){
618 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
619 return -1;
620 }
621 if(decode_stream_header(nut) >= 0)
622 initialized_stream_count++;
623 }
624
625 /* info headers */
626 pos=0;
627 for(;;){
628 uint64_t startcode= find_any_startcode(bc, pos);
629 pos= url_ftell(bc);
630
631 if(startcode==0){
632 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
633 return -1;
634 }else if(startcode == SYNCPOINT_STARTCODE){
635 nut->next_startcode= startcode;
636 break;
637 }else if(startcode != INFO_STARTCODE){
638 continue;
639 }
640
641 decode_info_header(nut);
642 }
643
644 s->data_offset= pos-8;
645
646 if(!url_is_streamed(bc)){
647 int64_t orig_pos= url_ftell(bc);
648 find_and_decode_index(nut);
649 url_fseek(bc, orig_pos, SEEK_SET);
650 }
651 assert(nut->next_startcode == SYNCPOINT_STARTCODE);
652
653 return 0;
654 }
655
656 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code){
657 AVFormatContext *s= nut->avf;
658 ByteIOContext *bc = s->pb;
659 StreamContext *stc;
660 int size, flags, size_mul, pts_delta, i, reserved_count;
661 uint64_t tmp;
662
663 if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){
664 av_log(s, AV_LOG_ERROR, "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n", url_ftell(bc), nut->last_syncpoint_pos, nut->max_distance);
665 return -1;
666 }
667
668 flags = nut->frame_code[frame_code].flags;
669 size_mul = nut->frame_code[frame_code].size_mul;
670 size = nut->frame_code[frame_code].size_lsb;
671 *stream_id = nut->frame_code[frame_code].stream_id;
672 pts_delta = nut->frame_code[frame_code].pts_delta;
673 reserved_count = nut->frame_code[frame_code].reserved_count;
674 *header_idx = nut->frame_code[frame_code].header_idx;
675
676 if(flags & FLAG_INVALID)
677 return -1;
678 if(flags & FLAG_CODED)
679 flags ^= ff_get_v(bc);
680 if(flags & FLAG_STREAM_ID){
681 GET_V(*stream_id, tmp < s->nb_streams)
682 }
683 stc= &nut->stream[*stream_id];
684 if(flags&FLAG_CODED_PTS){
685 int coded_pts= ff_get_v(bc);
686 //FIXME check last_pts validity?
687 if(coded_pts < (1<<stc->msb_pts_shift)){
688 *pts=ff_lsb2full(stc, coded_pts);
689 }else
690 *pts=coded_pts - (1<<stc->msb_pts_shift);
691 }else
692 *pts= stc->last_pts + pts_delta;
693 if(flags&FLAG_SIZE_MSB){
694 size += size_mul*ff_get_v(bc);
695 }
696 if(flags&FLAG_MATCH_TIME)
697 get_s(bc);
698 if(flags&FLAG_HEADER_IDX)
699 *header_idx= ff_get_v(bc);
700 if(flags&FLAG_RESERVED)
701 reserved_count= ff_get_v(bc);
702 for(i=0; i<reserved_count; i++)
703 ff_get_v(bc);
704
705 if(*header_idx >= (unsigned)nut->header_count){
706 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
707 return -1;
708 }
709 if(size > 4096)
710 *header_idx=0;
711 size -= nut->header_len[*header_idx];
712
713 if(flags&FLAG_CHECKSUM){
714 get_be32(bc); //FIXME check this
715 }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){
716 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
717 return -1;
718 }
719
720 stc->last_pts= *pts;
721 stc->last_flags= flags;
722
723 return size;
724 }
725
726 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){
727 AVFormatContext *s= nut->avf;
728 ByteIOContext *bc = s->pb;
729 int size, stream_id, discard;
730 int64_t pts, last_IP_pts;
731 StreamContext *stc;
732 uint8_t header_idx;
733
734 size= decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
735 if(size < 0)
736 return -1;
737
738 stc= &nut->stream[stream_id];
739
740 if (stc->last_flags & FLAG_KEY)
741 stc->skip_until_key_frame=0;
742
743 discard= s->streams[ stream_id ]->discard;
744 last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
745 if( (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY))
746 ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
747 || discard >= AVDISCARD_ALL
748 || stc->skip_until_key_frame){
749 url_fskip(bc, size);
750 return 1;
751 }
752
753 av_new_packet(pkt, size + nut->header_len[header_idx]);
754 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
755 pkt->pos= url_ftell(bc); //FIXME
756 get_buffer(bc, pkt->data + nut->header_len[header_idx], size);
757
758 pkt->stream_index = stream_id;
759 if (stc->last_flags & FLAG_KEY)
760 pkt->flags |= AV_PKT_FLAG_KEY;
761 pkt->pts = pts;
762
763 return 0;
764 }
765
766 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
767 {
768 NUTContext *nut = s->priv_data;
769 ByteIOContext *bc = s->pb;
770 int i, frame_code=0, ret, skip;
771 int64_t ts, back_ptr;
772
773 for(;;){
774 int64_t pos= url_ftell(bc);
775 uint64_t tmp= nut->next_startcode;
776 nut->next_startcode=0;
777
778 if(tmp){
779 pos-=8;
780 }else{
781 frame_code = get_byte(bc);
782 if(url_feof(bc))
783 return -1;
784 if(frame_code == 'N'){
785 tmp= frame_code;
786 for(i=1; i<8; i++)
787 tmp = (tmp<<8) + get_byte(bc);
788 }
789 }
790 switch(tmp){
791 case MAIN_STARTCODE:
792 case STREAM_STARTCODE:
793 case INDEX_STARTCODE:
794 skip= get_packetheader(nut, bc, 0, tmp);
795 url_fseek(bc, skip, SEEK_CUR);
796 break;
797 case INFO_STARTCODE:
798 if(decode_info_header(nut)<0)
799 goto resync;
800 break;
801 case SYNCPOINT_STARTCODE:
802 if(decode_syncpoint(nut, &ts, &back_ptr)<0)
803 goto resync;
804 frame_code = get_byte(bc);
805 case 0:
806 ret= decode_frame(nut, pkt, frame_code);
807 if(ret==0)
808 return 0;
809 else if(ret==1) //ok but discard packet
810 break;
811 default:
812 resync:
813 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
814 tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1);
815 if(tmp==0)
816 return -1;
817 av_log(s, AV_LOG_DEBUG, "sync\n");
818 nut->next_startcode= tmp;
819 }
820 }
821 }
822
823 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
824 NUTContext *nut = s->priv_data;
825 ByteIOContext *bc = s->pb;
826 int64_t pos, pts, back_ptr;
827 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit);
828
829 pos= *pos_arg;
830 do{
831 pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1;
832 if(pos < 1){
833 assert(nut->next_startcode == 0);
834 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
835 return AV_NOPTS_VALUE;
836 }
837 }while(decode_syncpoint(nut, &pts, &back_ptr) < 0);
838 *pos_arg = pos-1;
839 assert(nut->last_syncpoint_pos == *pos_arg);
840
841 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts,back_ptr );
842 if (stream_index == -1) return pts;
843 else if(stream_index == -2) return back_ptr;
844
845 assert(0);
846 }
847
848 static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){
849 NUTContext *nut = s->priv_data;
850 AVStream *st= s->streams[stream_index];
851 Syncpoint dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE};
852 Syncpoint nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE};
853 Syncpoint *sp, *next_node[2]= {&nopts_sp, &nopts_sp};
854 int64_t pos, pos2, ts;
855 int i;
856
857 if(st->index_entries){
858 int index= av_index_search_timestamp(st, pts, flags);
859 if(index<0)
860 return -1;
861
862 pos2= st->index_entries[index].pos;
863 ts = st->index_entries[index].timestamp;
864 }else{
865 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
866 (void **) next_node);
867 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos,
868 next_node[0]->ts , next_node[1]->ts);
869 pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos,
870 next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
871
872 if(!(flags & AVSEEK_FLAG_BACKWARD)){
873 dummy.pos= pos+16;
874 next_node[1]= &nopts_sp;
875 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
876 (void **) next_node);
877 pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos , next_node[1]->pos, next_node[1]->pos,
878 next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp);
879 if(pos2>=0)
880 pos= pos2;
881 //FIXME dir but I think it does not matter
882 }
883 dummy.pos= pos;
884 sp= av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
885 NULL);
886
887 assert(sp);
888 pos2= sp->back_ptr - 15;
889 }
890 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
891 pos= find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
892 url_fseek(s->pb, pos, SEEK_SET);
893 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
894 if(pos2 > pos || pos2 + 15 < pos){
895 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
896 }
897 for(i=0; i<s->nb_streams; i++)
898 nut->stream[i].skip_until_key_frame=1;
899
900 return 0;
901 }
902
903 static int nut_read_close(AVFormatContext *s)
904 {
905 NUTContext *nut = s->priv_data;
906 int i;
907
908 av_freep(&nut->time_base);
909 av_freep(&nut->stream);
910 ff_nut_free_sp(nut);
911 for(i = 1; i < nut->header_count; i++)
912 av_freep(&nut->header[i]);
913
914 return 0;
915 }
916
917 #if CONFIG_NUT_DEMUXER
918 AVInputFormat nut_demuxer = {
919 "nut",
920 NULL_IF_CONFIG_SMALL("NUT format"),
921 sizeof(NUTContext),
922 nut_probe,
923 nut_read_header,
924 nut_read_packet,
925 nut_read_close,
926 read_seek,
927 .extensions = "nut",
928 .metadata_conv = ff_nut_metadata_conv,
929 .codec_tag = (const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, ff_codec_wav_tags, ff_nut_subtitle_tags, 0 },
930 };
931 #endif