293f67ddc34ef65d5a32ed1325f08f915177d54e
[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 = ff_codec_get_id(ff_codec_bmp_tags, tmp);
320 break;
321 case 1:
322 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
323 st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, tmp);
324 break;
325 case 2:
326 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
327 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
328 break;
329 case 3:
330 st->codec->codec_type = AVMEDIA_TYPE_DATA;
331 break;
332 default:
333 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
334 return -1;
335 }
336 if(class<3 && st->codec->codec_id == CODEC_ID_NONE)
337 av_log(s, AV_LOG_ERROR, "Unknown codec tag '0x%04x' for stream number %d\n",
338 (unsigned int)tmp, stream_id);
339
340 GET_V(stc->time_base_id , tmp < nut->time_base_count);
341 GET_V(stc->msb_pts_shift , tmp < 16);
342 stc->max_pts_distance= ff_get_v(bc);
343 GET_V(stc->decode_delay , tmp < 1000); //sanity limit, raise this if Moore's law is true
344 st->codec->has_b_frames= stc->decode_delay;
345 ff_get_v(bc); //stream flags
346
347 GET_V(st->codec->extradata_size, tmp < (1<<30));
348 if(st->codec->extradata_size){
349 st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
350 get_buffer(bc, st->codec->extradata, st->codec->extradata_size);
351 }
352
353 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO){
354 GET_V(st->codec->width , tmp > 0)
355 GET_V(st->codec->height, tmp > 0)
356 st->sample_aspect_ratio.num= ff_get_v(bc);
357 st->sample_aspect_ratio.den= ff_get_v(bc);
358 if((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)){
359 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
360 return -1;
361 }
362 ff_get_v(bc); /* csp type */
363 }else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO){
364 GET_V(st->codec->sample_rate , tmp > 0)
365 ff_get_v(bc); // samplerate_den
366 GET_V(st->codec->channels, tmp > 0)
367 }
368 if(skip_reserved(bc, end) || get_checksum(bc)){
369 av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id);
370 return -1;
371 }
372 stc->time_base= &nut->time_base[stc->time_base_id];
373 av_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den);
374 return 0;
375 }
376
377 static void set_disposition_bits(AVFormatContext* avf, char* value, int stream_id){
378 int flag = 0, i;
379 for (i=0; ff_nut_dispositions[i].flag; ++i) {
380 if (!strcmp(ff_nut_dispositions[i].str, value))
381 flag = ff_nut_dispositions[i].flag;
382 }
383 if (!flag)
384 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
385 for (i = 0; i < avf->nb_streams; ++i)
386 if (stream_id == i || stream_id == -1)
387 avf->streams[i]->disposition |= flag;
388 }
389
390 static int decode_info_header(NUTContext *nut){
391 AVFormatContext *s= nut->avf;
392 ByteIOContext *bc = s->pb;
393 uint64_t tmp, chapter_start, chapter_len;
394 unsigned int stream_id_plus1, count;
395 int chapter_id, i;
396 int64_t value, end;
397 char name[256], str_value[1024], type_str[256];
398 const char *type;
399 AVChapter *chapter= NULL;
400 AVStream *st= NULL;
401
402 end= get_packetheader(nut, bc, 1, INFO_STARTCODE);
403 end += url_ftell(bc);
404
405 GET_V(stream_id_plus1, tmp <= s->nb_streams)
406 chapter_id = get_s(bc);
407 chapter_start= ff_get_v(bc);
408 chapter_len = ff_get_v(bc);
409 count = ff_get_v(bc);
410
411 if(chapter_id && !stream_id_plus1){
412 int64_t start= chapter_start / nut->time_base_count;
413 chapter= ff_new_chapter(s, chapter_id,
414 nut->time_base[chapter_start % nut->time_base_count],
415 start, start + chapter_len, NULL);
416 } else if(stream_id_plus1)
417 st= s->streams[stream_id_plus1 - 1];
418
419 for(i=0; i<count; i++){
420 get_str(bc, name, sizeof(name));
421 value= get_s(bc);
422 if(value == -1){
423 type= "UTF-8";
424 get_str(bc, str_value, sizeof(str_value));
425 }else if(value == -2){
426 get_str(bc, type_str, sizeof(type_str));
427 type= type_str;
428 get_str(bc, str_value, sizeof(str_value));
429 }else if(value == -3){
430 type= "s";
431 value= get_s(bc);
432 }else if(value == -4){
433 type= "t";
434 value= ff_get_v(bc);
435 }else if(value < -4){
436 type= "r";
437 get_s(bc);
438 }else{
439 type= "v";
440 }
441
442 if (stream_id_plus1 > s->nb_streams) {
443 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
444 continue;
445 }
446
447 if(!strcmp(type, "UTF-8")){
448 AVMetadata **metadata = NULL;
449 if(chapter_id==0 && !strcmp(name, "Disposition"))
450 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
451 else if(chapter) metadata= &chapter->metadata;
452 else if(stream_id_plus1) metadata= &st->metadata;
453 else metadata= &s->metadata;
454 if(metadata && strcasecmp(name,"Uses")
455 && strcasecmp(name,"Depends") && strcasecmp(name,"Replaces"))
456 av_metadata_set2(metadata, name, str_value, 0);
457 }
458 }
459
460 if(skip_reserved(bc, end) || get_checksum(bc)){
461 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
462 return -1;
463 }
464 return 0;
465 }
466
467 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){
468 AVFormatContext *s= nut->avf;
469 ByteIOContext *bc = s->pb;
470 int64_t end, tmp;
471
472 nut->last_syncpoint_pos= url_ftell(bc)-8;
473
474 end= get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
475 end += url_ftell(bc);
476
477 tmp= ff_get_v(bc);
478 *back_ptr= nut->last_syncpoint_pos - 16*ff_get_v(bc);
479 if(*back_ptr < 0)
480 return -1;
481
482 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count);
483
484 if(skip_reserved(bc, end) || get_checksum(bc)){
485 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
486 return -1;
487 }
488
489 *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE;
490 ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
491
492 return 0;
493 }
494
495 static int find_and_decode_index(NUTContext *nut){
496 AVFormatContext *s= nut->avf;
497 ByteIOContext *bc = s->pb;
498 uint64_t tmp, end;
499 int i, j, syncpoint_count;
500 int64_t filesize= url_fsize(bc);
501 int64_t *syncpoints;
502 int8_t *has_keyframe;
503 int ret= -1;
504
505 url_fseek(bc, filesize-12, SEEK_SET);
506 url_fseek(bc, filesize-get_be64(bc), SEEK_SET);
507 if(get_be64(bc) != INDEX_STARTCODE){
508 av_log(s, AV_LOG_ERROR, "no index at the end\n");
509 return -1;
510 }
511
512 end= get_packetheader(nut, bc, 1, INDEX_STARTCODE);
513 end += url_ftell(bc);
514
515 ff_get_v(bc); //max_pts
516 GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0)
517 syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count);
518 has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1));
519 for(i=0; i<syncpoint_count; i++){
520 syncpoints[i] = ff_get_v(bc);
521 if(syncpoints[i] <= 0)
522 goto fail;
523 if(i)
524 syncpoints[i] += syncpoints[i-1];
525 }
526
527 for(i=0; i<s->nb_streams; i++){
528 int64_t last_pts= -1;
529 for(j=0; j<syncpoint_count;){
530 uint64_t x= ff_get_v(bc);
531 int type= x&1;
532 int n= j;
533 x>>=1;
534 if(type){
535 int flag= x&1;
536 x>>=1;
537 if(n+x >= syncpoint_count + 1){
538 av_log(s, AV_LOG_ERROR, "index overflow A\n");
539 goto fail;
540 }
541 while(x--)
542 has_keyframe[n++]= flag;
543 has_keyframe[n++]= !flag;
544 }else{
545 while(x != 1){
546 if(n>=syncpoint_count + 1){
547 av_log(s, AV_LOG_ERROR, "index overflow B\n");
548 goto fail;
549 }
550 has_keyframe[n++]= x&1;
551 x>>=1;
552 }
553 }
554 if(has_keyframe[0]){
555 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
556 goto fail;
557 }
558 assert(n<=syncpoint_count+1);
559 for(; j<n && j<syncpoint_count; j++){
560 if(has_keyframe[j]){
561 uint64_t B, A= ff_get_v(bc);
562 if(!A){
563 A= ff_get_v(bc);
564 B= ff_get_v(bc);
565 //eor_pts[j][i] = last_pts + A + B
566 }else
567 B= 0;
568 av_add_index_entry(
569 s->streams[i],
570 16*syncpoints[j-1],
571 last_pts + A,
572 0,
573 0,
574 AVINDEX_KEYFRAME);
575 last_pts += A + B;
576 }
577 }
578 }
579 }
580
581 if(skip_reserved(bc, end) || get_checksum(bc)){
582 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
583 goto fail;
584 }
585 ret= 0;
586 fail:
587 av_free(syncpoints);
588 av_free(has_keyframe);
589 return ret;
590 }
591
592 static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
593 {
594 NUTContext *nut = s->priv_data;
595 ByteIOContext *bc = s->pb;
596 int64_t pos;
597 int initialized_stream_count;
598
599 nut->avf= s;
600
601 /* main header */
602 pos=0;
603 do{
604 pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
605 if (pos<0+1){
606 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
607 return -1;
608 }
609 }while(decode_main_header(nut) < 0);
610
611 /* stream headers */
612 pos=0;
613 for(initialized_stream_count=0; initialized_stream_count < s->nb_streams;){
614 pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
615 if (pos<0+1){
616 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
617 return -1;
618 }
619 if(decode_stream_header(nut) >= 0)
620 initialized_stream_count++;
621 }
622
623 /* info headers */
624 pos=0;
625 for(;;){
626 uint64_t startcode= find_any_startcode(bc, pos);
627 pos= url_ftell(bc);
628
629 if(startcode==0){
630 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
631 return -1;
632 }else if(startcode == SYNCPOINT_STARTCODE){
633 nut->next_startcode= startcode;
634 break;
635 }else if(startcode != INFO_STARTCODE){
636 continue;
637 }
638
639 decode_info_header(nut);
640 }
641
642 s->data_offset= pos-8;
643
644 if(!url_is_streamed(bc)){
645 int64_t orig_pos= url_ftell(bc);
646 find_and_decode_index(nut);
647 url_fseek(bc, orig_pos, SEEK_SET);
648 }
649 assert(nut->next_startcode == SYNCPOINT_STARTCODE);
650
651 return 0;
652 }
653
654 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code){
655 AVFormatContext *s= nut->avf;
656 ByteIOContext *bc = s->pb;
657 StreamContext *stc;
658 int size, flags, size_mul, pts_delta, i, reserved_count;
659 uint64_t tmp;
660
661 if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){
662 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);
663 return -1;
664 }
665
666 flags = nut->frame_code[frame_code].flags;
667 size_mul = nut->frame_code[frame_code].size_mul;
668 size = nut->frame_code[frame_code].size_lsb;
669 *stream_id = nut->frame_code[frame_code].stream_id;
670 pts_delta = nut->frame_code[frame_code].pts_delta;
671 reserved_count = nut->frame_code[frame_code].reserved_count;
672 *header_idx = nut->frame_code[frame_code].header_idx;
673
674 if(flags & FLAG_INVALID)
675 return -1;
676 if(flags & FLAG_CODED)
677 flags ^= ff_get_v(bc);
678 if(flags & FLAG_STREAM_ID){
679 GET_V(*stream_id, tmp < s->nb_streams)
680 }
681 stc= &nut->stream[*stream_id];
682 if(flags&FLAG_CODED_PTS){
683 int coded_pts= ff_get_v(bc);
684 //FIXME check last_pts validity?
685 if(coded_pts < (1<<stc->msb_pts_shift)){
686 *pts=ff_lsb2full(stc, coded_pts);
687 }else
688 *pts=coded_pts - (1<<stc->msb_pts_shift);
689 }else
690 *pts= stc->last_pts + pts_delta;
691 if(flags&FLAG_SIZE_MSB){
692 size += size_mul*ff_get_v(bc);
693 }
694 if(flags&FLAG_MATCH_TIME)
695 get_s(bc);
696 if(flags&FLAG_HEADER_IDX)
697 *header_idx= ff_get_v(bc);
698 if(flags&FLAG_RESERVED)
699 reserved_count= ff_get_v(bc);
700 for(i=0; i<reserved_count; i++)
701 ff_get_v(bc);
702
703 if(*header_idx >= (unsigned)nut->header_count){
704 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
705 return -1;
706 }
707 if(size > 4096)
708 *header_idx=0;
709 size -= nut->header_len[*header_idx];
710
711 if(flags&FLAG_CHECKSUM){
712 get_be32(bc); //FIXME check this
713 }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){
714 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
715 return -1;
716 }
717
718 stc->last_pts= *pts;
719 stc->last_flags= flags;
720
721 return size;
722 }
723
724 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){
725 AVFormatContext *s= nut->avf;
726 ByteIOContext *bc = s->pb;
727 int size, stream_id, discard;
728 int64_t pts, last_IP_pts;
729 StreamContext *stc;
730 uint8_t header_idx;
731
732 size= decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
733 if(size < 0)
734 return -1;
735
736 stc= &nut->stream[stream_id];
737
738 if (stc->last_flags & FLAG_KEY)
739 stc->skip_until_key_frame=0;
740
741 discard= s->streams[ stream_id ]->discard;
742 last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
743 if( (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY))
744 ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
745 || discard >= AVDISCARD_ALL
746 || stc->skip_until_key_frame){
747 url_fskip(bc, size);
748 return 1;
749 }
750
751 av_new_packet(pkt, size + nut->header_len[header_idx]);
752 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
753 pkt->pos= url_ftell(bc); //FIXME
754 get_buffer(bc, pkt->data + nut->header_len[header_idx], size);
755
756 pkt->stream_index = stream_id;
757 if (stc->last_flags & FLAG_KEY)
758 pkt->flags |= AV_PKT_FLAG_KEY;
759 pkt->pts = pts;
760
761 return 0;
762 }
763
764 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
765 {
766 NUTContext *nut = s->priv_data;
767 ByteIOContext *bc = s->pb;
768 int i, frame_code=0, ret, skip;
769 int64_t ts, back_ptr;
770
771 for(;;){
772 int64_t pos= url_ftell(bc);
773 uint64_t tmp= nut->next_startcode;
774 nut->next_startcode=0;
775
776 if(tmp){
777 pos-=8;
778 }else{
779 frame_code = get_byte(bc);
780 if(url_feof(bc))
781 return -1;
782 if(frame_code == 'N'){
783 tmp= frame_code;
784 for(i=1; i<8; i++)
785 tmp = (tmp<<8) + get_byte(bc);
786 }
787 }
788 switch(tmp){
789 case MAIN_STARTCODE:
790 case STREAM_STARTCODE:
791 case INDEX_STARTCODE:
792 skip= get_packetheader(nut, bc, 0, tmp);
793 url_fseek(bc, skip, SEEK_CUR);
794 break;
795 case INFO_STARTCODE:
796 if(decode_info_header(nut)<0)
797 goto resync;
798 break;
799 case SYNCPOINT_STARTCODE:
800 if(decode_syncpoint(nut, &ts, &back_ptr)<0)
801 goto resync;
802 frame_code = get_byte(bc);
803 case 0:
804 ret= decode_frame(nut, pkt, frame_code);
805 if(ret==0)
806 return 0;
807 else if(ret==1) //ok but discard packet
808 break;
809 default:
810 resync:
811 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
812 tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1);
813 if(tmp==0)
814 return -1;
815 av_log(s, AV_LOG_DEBUG, "sync\n");
816 nut->next_startcode= tmp;
817 }
818 }
819 }
820
821 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
822 NUTContext *nut = s->priv_data;
823 ByteIOContext *bc = s->pb;
824 int64_t pos, pts, back_ptr;
825 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit);
826
827 pos= *pos_arg;
828 do{
829 pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1;
830 if(pos < 1){
831 assert(nut->next_startcode == 0);
832 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
833 return AV_NOPTS_VALUE;
834 }
835 }while(decode_syncpoint(nut, &pts, &back_ptr) < 0);
836 *pos_arg = pos-1;
837 assert(nut->last_syncpoint_pos == *pos_arg);
838
839 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts,back_ptr );
840 if (stream_index == -1) return pts;
841 else if(stream_index == -2) return back_ptr;
842
843 assert(0);
844 }
845
846 static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){
847 NUTContext *nut = s->priv_data;
848 AVStream *st= s->streams[stream_index];
849 Syncpoint dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE};
850 Syncpoint nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE};
851 Syncpoint *sp, *next_node[2]= {&nopts_sp, &nopts_sp};
852 int64_t pos, pos2, ts;
853 int i;
854
855 if(st->index_entries){
856 int index= av_index_search_timestamp(st, pts, flags);
857 if(index<0)
858 return -1;
859
860 pos2= st->index_entries[index].pos;
861 ts = st->index_entries[index].timestamp;
862 }else{
863 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
864 (void **) next_node);
865 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos,
866 next_node[0]->ts , next_node[1]->ts);
867 pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos,
868 next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
869
870 if(!(flags & AVSEEK_FLAG_BACKWARD)){
871 dummy.pos= pos+16;
872 next_node[1]= &nopts_sp;
873 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
874 (void **) next_node);
875 pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos , next_node[1]->pos, next_node[1]->pos,
876 next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp);
877 if(pos2>=0)
878 pos= pos2;
879 //FIXME dir but I think it does not matter
880 }
881 dummy.pos= pos;
882 sp= av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
883 NULL);
884
885 assert(sp);
886 pos2= sp->back_ptr - 15;
887 }
888 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
889 pos= find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
890 url_fseek(s->pb, pos, SEEK_SET);
891 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
892 if(pos2 > pos || pos2 + 15 < pos){
893 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
894 }
895 for(i=0; i<s->nb_streams; i++)
896 nut->stream[i].skip_until_key_frame=1;
897
898 return 0;
899 }
900
901 static int nut_read_close(AVFormatContext *s)
902 {
903 NUTContext *nut = s->priv_data;
904 int i;
905
906 av_freep(&nut->time_base);
907 av_freep(&nut->stream);
908 ff_nut_free_sp(nut);
909 for(i = 1; i < nut->header_count; i++)
910 av_freep(&nut->header[i]);
911
912 return 0;
913 }
914
915 #if CONFIG_NUT_DEMUXER
916 AVInputFormat nut_demuxer = {
917 "nut",
918 NULL_IF_CONFIG_SMALL("NUT format"),
919 sizeof(NUTContext),
920 nut_probe,
921 nut_read_header,
922 nut_read_packet,
923 nut_read_close,
924 read_seek,
925 .extensions = "nut",
926 .metadata_conv = ff_nut_metadata_conv,
927 .codec_tag = (const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, ff_codec_wav_tags, ff_nut_subtitle_tags, 0 },
928 };
929 #endif