2 * "NUT" Container Format demuxer
3 * Copyright (c) 2004-2006 Michael Niedermayer
4 * Copyright (c) 2003 Alex Beregszaszi
6 * This file is part of FFmpeg.
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.
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.
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
24 #include "libavutil/avstring.h"
25 #include "libavutil/bswap.h"
26 #include "libavutil/tree.h"
32 #if LAVF_API_MAX_STREAMS
33 #define NUT_MAX_STREAMS MAX_STREAMS
35 #define NUT_MAX_STREAMS 256 /* arbitrary sanity check value */
38 static int get_str(ByteIOContext *bc, char *string, unsigned int maxlen){
39 unsigned int len= ff_get_v(bc);
42 get_buffer(bc, string, FFMIN(len, maxlen));
49 string[FFMIN(len, maxlen-1)]= 0;
57 static int64_t get_s(ByteIOContext *bc){
58 int64_t v = ff_get_v(bc) + 1;
60 if (v&1) return -(v>>1);
64 static uint64_t get_fourcc(ByteIOContext *bc){
65 unsigned int len= ff_get_v(bc);
67 if (len==2) return get_le16(bc);
68 else if(len==4) return get_le32(bc);
73 static inline uint64_t get_v_trace(ByteIOContext *bc, char *file, char *func, int line){
74 uint64_t v= ff_get_v(bc);
76 av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
80 static inline int64_t get_s_trace(ByteIOContext *bc, char *file, char *func, int line){
83 av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
87 static inline uint64_t get_vb_trace(ByteIOContext *bc, char *file, char *func, int line){
88 uint64_t v= get_vb(bc);
90 av_log(NULL, AV_LOG_DEBUG, "get_vb %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
93 #define ff_get_v(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
94 #define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
95 #define get_vb(bc) get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
98 static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int calculate_checksum, uint64_t startcode)
101 // start= url_ftell(bc) - 8;
103 startcode= av_be2ne64(startcode);
104 startcode= ff_crc04C11DB7_update(0, (uint8_t*)&startcode, 8);
106 init_checksum(bc, ff_crc04C11DB7_update, startcode);
110 if(get_checksum(bc) && size > 4096)
113 init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
118 static uint64_t find_any_startcode(ByteIOContext *bc, int64_t pos){
122 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
124 while(!url_feof(bc)){
125 state= (state<<8) | get_byte(bc);
126 if((state>>56) != 'N')
130 case STREAM_STARTCODE:
131 case SYNCPOINT_STARTCODE:
133 case INDEX_STARTCODE:
142 * Find the given startcode.
143 * @param code the startcode
144 * @param pos the start position of the search, or -1 if the current position
145 * @return the position of the startcode or -1 if not found
147 static int64_t find_startcode(ByteIOContext *bc, uint64_t code, int64_t pos){
149 uint64_t startcode= find_any_startcode(bc, pos);
150 if(startcode == code)
151 return url_ftell(bc) - 8;
152 else if(startcode == 0)
158 static int nut_probe(AVProbeData *p){
162 for (i = 0; i < p->buf_size; i++) {
163 code = (code << 8) | p->buf[i];
164 if (code == MAIN_STARTCODE)
165 return AVPROBE_SCORE_MAX;
170 #define GET_V(dst, check) \
173 av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp);\
178 static int skip_reserved(ByteIOContext *bc, int64_t pos){
179 pos -= url_ftell(bc);
181 url_fseek(bc, pos, SEEK_CUR);
190 static int decode_main_header(NUTContext *nut){
191 AVFormatContext *s= nut->avf;
192 ByteIOContext *bc = s->pb;
194 unsigned int stream_count;
195 int i, j, tmp_stream, tmp_mul, tmp_pts, tmp_size, count, tmp_res, tmp_head_idx;
198 end= get_packetheader(nut, bc, 1, MAIN_STARTCODE);
199 end += url_ftell(bc);
201 GET_V(tmp , tmp >=2 && tmp <= 3)
202 GET_V(stream_count , tmp > 0 && tmp <= NUT_MAX_STREAMS)
204 nut->max_distance = ff_get_v(bc);
205 if(nut->max_distance > 65536){
206 av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
207 nut->max_distance= 65536;
210 GET_V(nut->time_base_count, tmp>0 && tmp<INT_MAX / sizeof(AVRational))
211 nut->time_base= av_malloc(nut->time_base_count * sizeof(AVRational));
213 for(i=0; i<nut->time_base_count; i++){
214 GET_V(nut->time_base[i].num, tmp>0 && tmp<(1ULL<<31))
215 GET_V(nut->time_base[i].den, tmp>0 && tmp<(1ULL<<31))
216 if(av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1){
217 av_log(s, AV_LOG_ERROR, "time base invalid\n");
224 tmp_match= 1-(1LL<<62);
227 int tmp_flags = ff_get_v(bc);
228 int tmp_fields= ff_get_v(bc);
229 if(tmp_fields>0) tmp_pts = get_s(bc);
230 if(tmp_fields>1) tmp_mul = ff_get_v(bc);
231 if(tmp_fields>2) tmp_stream= ff_get_v(bc);
232 if(tmp_fields>3) tmp_size = ff_get_v(bc);
234 if(tmp_fields>4) tmp_res = ff_get_v(bc);
236 if(tmp_fields>5) count = ff_get_v(bc);
237 else count = tmp_mul - tmp_size;
238 if(tmp_fields>6) tmp_match = get_s(bc);
239 if(tmp_fields>7) tmp_head_idx= ff_get_v(bc);
241 while(tmp_fields-- > 8)
244 if(count == 0 || i+count > 256){
245 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
248 if(tmp_stream >= stream_count){
249 av_log(s, AV_LOG_ERROR, "illegal stream number\n");
253 for(j=0; j<count; j++,i++){
255 nut->frame_code[i].flags= FLAG_INVALID;
259 nut->frame_code[i].flags = tmp_flags ;
260 nut->frame_code[i].pts_delta = tmp_pts ;
261 nut->frame_code[i].stream_id = tmp_stream;
262 nut->frame_code[i].size_mul = tmp_mul ;
263 nut->frame_code[i].size_lsb = tmp_size+j;
264 nut->frame_code[i].reserved_count = tmp_res ;
265 nut->frame_code[i].header_idx = tmp_head_idx;
268 assert(nut->frame_code['N'].flags == FLAG_INVALID);
270 if(end > url_ftell(bc) + 4){
272 GET_V(nut->header_count, tmp<128U)
274 for(i=1; i<nut->header_count; i++){
275 GET_V(nut->header_len[i], tmp>0 && tmp<256);
276 rem -= nut->header_len[i];
278 av_log(s, AV_LOG_ERROR, "invalid elision header\n");
281 nut->header[i]= av_malloc(nut->header_len[i]);
282 get_buffer(bc, nut->header[i], nut->header_len[i]);
284 assert(nut->header_len[0]==0);
287 if(skip_reserved(bc, end) || get_checksum(bc)){
288 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
292 nut->stream = av_mallocz(sizeof(StreamContext)*stream_count);
293 for(i=0; i<stream_count; i++){
300 static int decode_stream_header(NUTContext *nut){
301 AVFormatContext *s= nut->avf;
302 ByteIOContext *bc = s->pb;
304 int class, stream_id;
308 end= get_packetheader(nut, bc, 1, STREAM_STARTCODE);
309 end += url_ftell(bc);
311 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
312 stc= &nut->stream[stream_id];
314 st = s->streams[stream_id];
316 return AVERROR(ENOMEM);
318 class = ff_get_v(bc);
319 tmp = get_fourcc(bc);
320 st->codec->codec_tag= tmp;
324 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
325 st->codec->codec_id = av_codec_get_id(
326 (const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, 0 },
330 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
331 st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, tmp);
334 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
335 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
338 st->codec->codec_type = AVMEDIA_TYPE_DATA;
341 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
344 if(class<3 && st->codec->codec_id == CODEC_ID_NONE)
345 av_log(s, AV_LOG_ERROR, "Unknown codec tag '0x%04x' for stream number %d\n",
346 (unsigned int)tmp, stream_id);
348 GET_V(stc->time_base_id , tmp < nut->time_base_count);
349 GET_V(stc->msb_pts_shift , tmp < 16);
350 stc->max_pts_distance= ff_get_v(bc);
351 GET_V(stc->decode_delay , tmp < 1000); //sanity limit, raise this if Moore's law is true
352 st->codec->has_b_frames= stc->decode_delay;
353 ff_get_v(bc); //stream flags
355 GET_V(st->codec->extradata_size, tmp < (1<<30));
356 if(st->codec->extradata_size){
357 st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
358 get_buffer(bc, st->codec->extradata, st->codec->extradata_size);
361 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO){
362 GET_V(st->codec->width , tmp > 0)
363 GET_V(st->codec->height, tmp > 0)
364 st->sample_aspect_ratio.num= ff_get_v(bc);
365 st->sample_aspect_ratio.den= ff_get_v(bc);
366 if((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)){
367 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
370 ff_get_v(bc); /* csp type */
371 }else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO){
372 GET_V(st->codec->sample_rate , tmp > 0)
373 ff_get_v(bc); // samplerate_den
374 GET_V(st->codec->channels, tmp > 0)
376 if(skip_reserved(bc, end) || get_checksum(bc)){
377 av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id);
380 stc->time_base= &nut->time_base[stc->time_base_id];
381 av_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den);
385 static void set_disposition_bits(AVFormatContext* avf, char* value, int stream_id){
387 for (i=0; ff_nut_dispositions[i].flag; ++i) {
388 if (!strcmp(ff_nut_dispositions[i].str, value))
389 flag = ff_nut_dispositions[i].flag;
392 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
393 for (i = 0; i < avf->nb_streams; ++i)
394 if (stream_id == i || stream_id == -1)
395 avf->streams[i]->disposition |= flag;
398 static int decode_info_header(NUTContext *nut){
399 AVFormatContext *s= nut->avf;
400 ByteIOContext *bc = s->pb;
401 uint64_t tmp, chapter_start, chapter_len;
402 unsigned int stream_id_plus1, count;
405 char name[256], str_value[1024], type_str[256];
407 AVChapter *chapter= NULL;
410 end= get_packetheader(nut, bc, 1, INFO_STARTCODE);
411 end += url_ftell(bc);
413 GET_V(stream_id_plus1, tmp <= s->nb_streams)
414 chapter_id = get_s(bc);
415 chapter_start= ff_get_v(bc);
416 chapter_len = ff_get_v(bc);
417 count = ff_get_v(bc);
419 if(chapter_id && !stream_id_plus1){
420 int64_t start= chapter_start / nut->time_base_count;
421 chapter= ff_new_chapter(s, chapter_id,
422 nut->time_base[chapter_start % nut->time_base_count],
423 start, start + chapter_len, NULL);
424 } else if(stream_id_plus1)
425 st= s->streams[stream_id_plus1 - 1];
427 for(i=0; i<count; i++){
428 get_str(bc, name, sizeof(name));
432 get_str(bc, str_value, sizeof(str_value));
433 }else if(value == -2){
434 get_str(bc, type_str, sizeof(type_str));
436 get_str(bc, str_value, sizeof(str_value));
437 }else if(value == -3){
440 }else if(value == -4){
443 }else if(value < -4){
450 if (stream_id_plus1 > s->nb_streams) {
451 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
455 if(!strcmp(type, "UTF-8")){
456 AVMetadata **metadata = NULL;
457 if(chapter_id==0 && !strcmp(name, "Disposition"))
458 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
459 else if(chapter) metadata= &chapter->metadata;
460 else if(stream_id_plus1) metadata= &st->metadata;
461 else metadata= &s->metadata;
462 if(metadata && strcasecmp(name,"Uses")
463 && strcasecmp(name,"Depends") && strcasecmp(name,"Replaces"))
464 av_metadata_set2(metadata, name, str_value, 0);
468 if(skip_reserved(bc, end) || get_checksum(bc)){
469 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
475 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){
476 AVFormatContext *s= nut->avf;
477 ByteIOContext *bc = s->pb;
480 nut->last_syncpoint_pos= url_ftell(bc)-8;
482 end= get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
483 end += url_ftell(bc);
486 *back_ptr= nut->last_syncpoint_pos - 16*ff_get_v(bc);
490 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count);
492 if(skip_reserved(bc, end) || get_checksum(bc)){
493 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
497 *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE;
498 ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
503 static int find_and_decode_index(NUTContext *nut){
504 AVFormatContext *s= nut->avf;
505 ByteIOContext *bc = s->pb;
507 int i, j, syncpoint_count;
508 int64_t filesize= url_fsize(bc);
510 int8_t *has_keyframe;
513 url_fseek(bc, filesize-12, SEEK_SET);
514 url_fseek(bc, filesize-get_be64(bc), SEEK_SET);
515 if(get_be64(bc) != INDEX_STARTCODE){
516 av_log(s, AV_LOG_ERROR, "no index at the end\n");
520 end= get_packetheader(nut, bc, 1, INDEX_STARTCODE);
521 end += url_ftell(bc);
523 ff_get_v(bc); //max_pts
524 GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0)
525 syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count);
526 has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1));
527 for(i=0; i<syncpoint_count; i++){
528 syncpoints[i] = ff_get_v(bc);
529 if(syncpoints[i] <= 0)
532 syncpoints[i] += syncpoints[i-1];
535 for(i=0; i<s->nb_streams; i++){
536 int64_t last_pts= -1;
537 for(j=0; j<syncpoint_count;){
538 uint64_t x= ff_get_v(bc);
545 if(n+x >= syncpoint_count + 1){
546 av_log(s, AV_LOG_ERROR, "index overflow A\n");
550 has_keyframe[n++]= flag;
551 has_keyframe[n++]= !flag;
554 if(n>=syncpoint_count + 1){
555 av_log(s, AV_LOG_ERROR, "index overflow B\n");
558 has_keyframe[n++]= x&1;
563 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
566 assert(n<=syncpoint_count+1);
567 for(; j<n && j<syncpoint_count; j++){
569 uint64_t B, A= ff_get_v(bc);
573 //eor_pts[j][i] = last_pts + A + B
589 if(skip_reserved(bc, end) || get_checksum(bc)){
590 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
596 av_free(has_keyframe);
600 static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
602 NUTContext *nut = s->priv_data;
603 ByteIOContext *bc = s->pb;
605 int initialized_stream_count;
612 pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
614 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
617 }while(decode_main_header(nut) < 0);
621 for(initialized_stream_count=0; initialized_stream_count < s->nb_streams;){
622 pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
624 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
627 if(decode_stream_header(nut) >= 0)
628 initialized_stream_count++;
634 uint64_t startcode= find_any_startcode(bc, pos);
638 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
640 }else if(startcode == SYNCPOINT_STARTCODE){
641 nut->next_startcode= startcode;
643 }else if(startcode != INFO_STARTCODE){
647 decode_info_header(nut);
650 s->data_offset= pos-8;
652 if(!url_is_streamed(bc)){
653 int64_t orig_pos= url_ftell(bc);
654 find_and_decode_index(nut);
655 url_fseek(bc, orig_pos, SEEK_SET);
657 assert(nut->next_startcode == SYNCPOINT_STARTCODE);
662 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code){
663 AVFormatContext *s= nut->avf;
664 ByteIOContext *bc = s->pb;
666 int size, flags, size_mul, pts_delta, i, reserved_count;
669 if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){
670 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);
674 flags = nut->frame_code[frame_code].flags;
675 size_mul = nut->frame_code[frame_code].size_mul;
676 size = nut->frame_code[frame_code].size_lsb;
677 *stream_id = nut->frame_code[frame_code].stream_id;
678 pts_delta = nut->frame_code[frame_code].pts_delta;
679 reserved_count = nut->frame_code[frame_code].reserved_count;
680 *header_idx = nut->frame_code[frame_code].header_idx;
682 if(flags & FLAG_INVALID)
684 if(flags & FLAG_CODED)
685 flags ^= ff_get_v(bc);
686 if(flags & FLAG_STREAM_ID){
687 GET_V(*stream_id, tmp < s->nb_streams)
689 stc= &nut->stream[*stream_id];
690 if(flags&FLAG_CODED_PTS){
691 int coded_pts= ff_get_v(bc);
692 //FIXME check last_pts validity?
693 if(coded_pts < (1<<stc->msb_pts_shift)){
694 *pts=ff_lsb2full(stc, coded_pts);
696 *pts=coded_pts - (1<<stc->msb_pts_shift);
698 *pts= stc->last_pts + pts_delta;
699 if(flags&FLAG_SIZE_MSB){
700 size += size_mul*ff_get_v(bc);
702 if(flags&FLAG_MATCH_TIME)
704 if(flags&FLAG_HEADER_IDX)
705 *header_idx= ff_get_v(bc);
706 if(flags&FLAG_RESERVED)
707 reserved_count= ff_get_v(bc);
708 for(i=0; i<reserved_count; i++)
711 if(*header_idx >= (unsigned)nut->header_count){
712 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
717 size -= nut->header_len[*header_idx];
719 if(flags&FLAG_CHECKSUM){
720 get_be32(bc); //FIXME check this
721 }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){
722 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
727 stc->last_flags= flags;
732 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){
733 AVFormatContext *s= nut->avf;
734 ByteIOContext *bc = s->pb;
735 int size, stream_id, discard;
736 int64_t pts, last_IP_pts;
740 size= decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
744 stc= &nut->stream[stream_id];
746 if (stc->last_flags & FLAG_KEY)
747 stc->skip_until_key_frame=0;
749 discard= s->streams[ stream_id ]->discard;
750 last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
751 if( (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY))
752 ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
753 || discard >= AVDISCARD_ALL
754 || stc->skip_until_key_frame){
759 av_new_packet(pkt, size + nut->header_len[header_idx]);
760 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
761 pkt->pos= url_ftell(bc); //FIXME
762 get_buffer(bc, pkt->data + nut->header_len[header_idx], size);
764 pkt->stream_index = stream_id;
765 if (stc->last_flags & FLAG_KEY)
766 pkt->flags |= AV_PKT_FLAG_KEY;
772 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
774 NUTContext *nut = s->priv_data;
775 ByteIOContext *bc = s->pb;
776 int i, frame_code=0, ret, skip;
777 int64_t ts, back_ptr;
780 int64_t pos= url_ftell(bc);
781 uint64_t tmp= nut->next_startcode;
782 nut->next_startcode=0;
787 frame_code = get_byte(bc);
790 if(frame_code == 'N'){
793 tmp = (tmp<<8) + get_byte(bc);
798 case STREAM_STARTCODE:
799 case INDEX_STARTCODE:
800 skip= get_packetheader(nut, bc, 0, tmp);
801 url_fseek(bc, skip, SEEK_CUR);
804 if(decode_info_header(nut)<0)
807 case SYNCPOINT_STARTCODE:
808 if(decode_syncpoint(nut, &ts, &back_ptr)<0)
810 frame_code = get_byte(bc);
812 ret= decode_frame(nut, pkt, frame_code);
815 else if(ret==1) //ok but discard packet
819 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
820 tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1);
823 av_log(s, AV_LOG_DEBUG, "sync\n");
824 nut->next_startcode= tmp;
829 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
830 NUTContext *nut = s->priv_data;
831 ByteIOContext *bc = s->pb;
832 int64_t pos, pts, back_ptr;
833 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit);
837 pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1;
839 assert(nut->next_startcode == 0);
840 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
841 return AV_NOPTS_VALUE;
843 }while(decode_syncpoint(nut, &pts, &back_ptr) < 0);
845 assert(nut->last_syncpoint_pos == *pos_arg);
847 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts,back_ptr );
848 if (stream_index == -1) return pts;
849 else if(stream_index == -2) return back_ptr;
854 static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){
855 NUTContext *nut = s->priv_data;
856 AVStream *st= s->streams[stream_index];
857 Syncpoint dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE};
858 Syncpoint nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE};
859 Syncpoint *sp, *next_node[2]= {&nopts_sp, &nopts_sp};
860 int64_t pos, pos2, ts;
863 if(st->index_entries){
864 int index= av_index_search_timestamp(st, pts, flags);
868 pos2= st->index_entries[index].pos;
869 ts = st->index_entries[index].timestamp;
871 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
872 (void **) next_node);
873 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos,
874 next_node[0]->ts , next_node[1]->ts);
875 pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos,
876 next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
878 if(!(flags & AVSEEK_FLAG_BACKWARD)){
880 next_node[1]= &nopts_sp;
881 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
882 (void **) next_node);
883 pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos , next_node[1]->pos, next_node[1]->pos,
884 next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp);
887 //FIXME dir but I think it does not matter
890 sp= av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
894 pos2= sp->back_ptr - 15;
896 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
897 pos= find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
898 url_fseek(s->pb, pos, SEEK_SET);
899 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
900 if(pos2 > pos || pos2 + 15 < pos){
901 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
903 for(i=0; i<s->nb_streams; i++)
904 nut->stream[i].skip_until_key_frame=1;
909 static int nut_read_close(AVFormatContext *s)
911 NUTContext *nut = s->priv_data;
914 av_freep(&nut->time_base);
915 av_freep(&nut->stream);
917 for(i = 1; i < nut->header_count; i++)
918 av_freep(&nut->header[i]);
923 #if CONFIG_NUT_DEMUXER
924 AVInputFormat nut_demuxer = {
926 NULL_IF_CONFIG_SMALL("NUT format"),
934 .metadata_conv = ff_nut_metadata_conv,
935 .codec_tag = (const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, ff_codec_wav_tags, ff_nut_subtitle_tags, 0 },