b33e4ca52b70ebabc19664fca9a41475906dd3ce
[libav.git] / libavformat / nut.c
1 /*
2 * "NUT" Container Format muxer and demuxer (DRAFT-200403??)
3 * Copyright (c) 2003 Alex Beregszaszi
4 * Copyright (c) 2004 Michael Niedermayer
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 *
21 * Visit the official site at http://www.nut.hu/
22 *
23 */
24
25 /*
26 * TODO:
27 * - index writing
28 * - index packet reading support
29 */
30
31 //#define DEBUG 1
32
33 #include <limits.h>
34 #include "avformat.h"
35 #include "mpegaudio.h"
36 #include "avi.h"
37
38 #undef NDEBUG
39 #include <assert.h>
40
41 //#define TRACE
42
43 //from /dev/random
44
45 #define MAIN_STARTCODE (0x7A561F5F04ADULL + (((uint64_t)('N'<<8) + 'M')<<48))
46 #define STREAM_STARTCODE (0x11405BF2F9DBULL + (((uint64_t)('N'<<8) + 'S')<<48))
47 #define KEYFRAME_STARTCODE (0xE4ADEECA4569ULL + (((uint64_t)('N'<<8) + 'K')<<48))
48 #define INDEX_STARTCODE (0xDD672F23E64EULL + (((uint64_t)('N'<<8) + 'X')<<48))
49 #define INFO_STARTCODE (0xAB68B596BA78ULL + (((uint64_t)('N'<<8) + 'I')<<48))
50
51 #define ID_STRING "nut/multimedia container\0"
52
53 #define MAX_DISTANCE (1024*16-1)
54 #define MAX_SHORT_DISTANCE (1024*4-1)
55
56 #define FLAG_DATA_SIZE 1
57 #define FLAG_KEY_FRAME 2
58 #define FLAG_INVALID 4
59
60 typedef struct {
61 uint8_t flags;
62 uint8_t stream_id_plus1;
63 uint16_t size_mul;
64 uint16_t size_lsb;
65 int16_t timestamp_delta;
66 uint8_t reserved_count;
67 } FrameCode;
68
69 typedef struct {
70 int last_key_frame;
71 int msb_timestamp_shift;
72 int rate_num;
73 int rate_den;
74 int64_t last_pts;
75 int64_t last_sync_pos; ///<pos of last 1/2 type frame
76 int decode_delay;
77 } StreamContext;
78
79 typedef struct {
80 AVFormatContext *avf;
81 int written_packet_size;
82 int64_t packet_start[3]; //0-> startcode less, 1-> short startcode 2-> long startcodes
83 FrameCode frame_code[256];
84 unsigned int stream_count;
85 uint64_t next_startcode; ///< stores the next startcode if it has alraedy been parsed but the stream isnt seekable
86 StreamContext *stream;
87 int max_distance;
88 int max_short_distance;
89 int rate_num;
90 int rate_den;
91 int short_startcode;
92 } NUTContext;
93
94 static char *info_table[][2]={
95 {NULL , NULL }, // end
96 {NULL , NULL },
97 {NULL , "UTF8"},
98 {NULL , "v"},
99 {NULL , "s"},
100 {"StreamId" , "v"},
101 {"SegmentId" , "v"},
102 {"StartTimestamp" , "v"},
103 {"EndTimestamp" , "v"},
104 {"Author" , "UTF8"},
105 {"Title" , "UTF8"},
106 {"Description" , "UTF8"},
107 {"Copyright" , "UTF8"},
108 {"Encoder" , "UTF8"},
109 {"Keyword" , "UTF8"},
110 {"Cover" , "JPEG"},
111 {"Cover" , "PNG"},
112 };
113
114 void ff_parse_specific_params(AVCodecContext *stream, int *au_rate, int *au_ssize, int *au_scale);
115
116 static void update(NUTContext *nut, int stream_index, int64_t frame_start, int frame_type, int frame_code, int key_frame, int size, int64_t pts){
117 StreamContext *stream= &nut->stream[stream_index];
118
119 stream->last_key_frame= key_frame;
120 nut->packet_start[ frame_type ]= frame_start;
121 stream->last_pts= pts;
122 }
123
124 static void reset(AVFormatContext *s, int64_t global_ts){
125 NUTContext *nut = s->priv_data;
126 int i;
127
128 for(i=0; i<s->nb_streams; i++){
129 StreamContext *stream= &nut->stream[i];
130
131 stream->last_key_frame= 1;
132
133 stream->last_pts= av_rescale(global_ts, stream->rate_num*(int64_t)nut->rate_den, stream->rate_den*(int64_t)nut->rate_num);
134 }
135 }
136
137 static void build_frame_code(AVFormatContext *s){
138 NUTContext *nut = s->priv_data;
139 int key_frame, index, pred, stream_id;
140 int start=0;
141 int end= 255;
142 int keyframe_0_esc= s->nb_streams > 2;
143 int pred_table[10];
144
145 if(keyframe_0_esc){
146 /* keyframe = 0 escape */
147 FrameCode *ft= &nut->frame_code[start];
148 ft->flags= FLAG_DATA_SIZE;
149 ft->stream_id_plus1= 0;
150 ft->size_mul=1;
151 ft->timestamp_delta=0;
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 == CODEC_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_FRAME*key_frame;
170 ft->flags|= FLAG_DATA_SIZE;
171 ft->stream_id_plus1= stream_id + 1;
172 ft->size_mul=1;
173 ft->timestamp_delta=0;
174 start2++;
175 }
176 }
177
178 key_frame= intra_only;
179 #if 1
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_FRAME*key_frame;
187 ft->stream_id_plus1= stream_id + 1;
188 ft->size_mul=frame_bytes + 2;
189 ft->size_lsb=frame_bytes + pred;
190 ft->timestamp_delta=pts;
191 start2++;
192 }
193 }
194 }else{
195 FrameCode *ft= &nut->frame_code[start2];
196 ft->flags= FLAG_KEY_FRAME | FLAG_DATA_SIZE;
197 ft->stream_id_plus1= stream_id + 1;
198 ft->size_mul=1;
199 ft->timestamp_delta=1;
200 start2++;
201 }
202 #endif
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_FRAME*key_frame;
228 ft->flags|= FLAG_DATA_SIZE;
229 ft->stream_id_plus1= stream_id + 1;
230 //FIXME use single byte size and pred from last
231 ft->size_mul= end3-start3;
232 ft->size_lsb= index - start3;
233 ft->timestamp_delta= pred_table[pred];
234 }
235 }
236 }
237 memmove(&nut->frame_code['N'+1], &nut->frame_code['N'], sizeof(FrameCode)*(255-'N'));
238 nut->frame_code['N'].flags= FLAG_INVALID;
239 }
240
241 static uint64_t get_v(ByteIOContext *bc)
242 {
243 uint64_t val = 0;
244
245 for(;;)
246 {
247 int tmp = get_byte(bc);
248
249 if (tmp&0x80)
250 val= (val<<7) + tmp - 0x80;
251 else{
252 //av_log(NULL, AV_LOG_DEBUG, "get_v()= %lld\n", (val<<7) + tmp);
253 return (val<<7) + tmp;
254 }
255 }
256 return -1;
257 }
258
259 static int get_str(ByteIOContext *bc, char *string, unsigned int maxlen){
260 unsigned int len= get_v(bc);
261
262 if(len && maxlen)
263 get_buffer(bc, string, FFMIN(len, maxlen));
264 while(len > maxlen){
265 get_byte(bc);
266 len--;
267 }
268
269 if(maxlen)
270 string[FFMIN(len, maxlen-1)]= 0;
271
272 if(maxlen == len)
273 return -1;
274 else
275 return 0;
276 }
277
278 static int64_t get_s(ByteIOContext *bc){
279 int64_t v = get_v(bc) + 1;
280
281 if (v&1) return -(v>>1);
282 else return (v>>1);
283 }
284
285 static uint64_t get_vb(ByteIOContext *bc){
286 uint64_t val=0;
287 unsigned int i= get_v(bc);
288
289 if(i>8)
290 return UINT64_MAX;
291
292 while(i--)
293 val = (val<<8) + get_byte(bc);
294
295 //av_log(NULL, AV_LOG_DEBUG, "get_vb()= %lld\n", val);
296 return val;
297 }
298
299 #ifdef TRACE
300 static inline uint64_t get_v_trace(ByteIOContext *bc, char *file, char *func, int line){
301 uint64_t v= get_v(bc);
302
303 printf("get_v %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
304 return v;
305 }
306
307 static inline int64_t get_s_trace(ByteIOContext *bc, char *file, char *func, int line){
308 int64_t v= get_s(bc);
309
310 printf("get_s %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
311 return v;
312 }
313
314 static inline uint64_t get_vb_trace(ByteIOContext *bc, char *file, char *func, int line){
315 uint64_t v= get_vb(bc);
316
317 printf("get_vb %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
318 return v;
319 }
320 #define get_v(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
321 #define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
322 #define get_vb(bc) get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
323 #endif
324
325
326 static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int calculate_checksum)
327 {
328 int64_t start, size;
329 start= url_ftell(bc) - 8;
330
331 size= get_v(bc);
332
333 init_checksum(bc, calculate_checksum ? update_adler32 : NULL, 0);
334
335 nut->packet_start[2] = start;
336 nut->written_packet_size= size;
337
338 return size;
339 }
340
341 static int check_checksum(ByteIOContext *bc){
342 unsigned long checksum= get_checksum(bc);
343 return checksum != get_be32(bc);
344 }
345
346 /**
347 *
348 */
349 static int get_length(uint64_t val){
350 int i;
351
352 for (i=7; val>>i; i+=7);
353
354 return i;
355 }
356
357 static uint64_t find_any_startcode(ByteIOContext *bc, int64_t pos){
358 uint64_t state=0;
359
360 if(pos >= 0)
361 url_fseek(bc, pos, SEEK_SET); //note, this may fail if the stream isnt seekable, but that shouldnt matter, as in this case we simply start where we are currently
362
363 while(!url_feof(bc)){
364 state= (state<<8) | get_byte(bc);
365 if((state>>56) != 'N')
366 continue;
367 switch(state){
368 case MAIN_STARTCODE:
369 case STREAM_STARTCODE:
370 case KEYFRAME_STARTCODE:
371 case INFO_STARTCODE:
372 case INDEX_STARTCODE:
373 return state;
374 }
375 }
376
377 return 0;
378 }
379
380 /**
381 * find the given startcode.
382 * @param code the startcode
383 * @param pos the start position of the search, or -1 if the current position
384 * @returns the position of the startcode or -1 if not found
385 */
386 static int64_t find_startcode(ByteIOContext *bc, uint64_t code, int64_t pos){
387 for(;;){
388 uint64_t startcode= find_any_startcode(bc, pos);
389 if(startcode == code)
390 return url_ftell(bc) - 8;
391 else if(startcode == 0)
392 return -1;
393 pos=-1;
394 }
395 }
396
397 #ifdef CONFIG_MUXERS
398
399 static void put_v(ByteIOContext *bc, uint64_t val)
400 {
401 int i;
402
403 //av_log(NULL, AV_LOG_DEBUG, "put_v()= %lld\n", val);
404 val &= 0x7FFFFFFFFFFFFFFFULL; // FIXME can only encode upto 63 bits currently
405 i= get_length(val);
406
407 for (i-=7; i>0; i-=7){
408 put_byte(bc, 0x80 | (val>>i));
409 }
410
411 put_byte(bc, val&0x7f);
412 }
413
414 /**
415 * stores a string as vb.
416 */
417 static void put_str(ByteIOContext *bc, const char *string){
418 int len= strlen(string);
419
420 put_v(bc, len);
421 put_buffer(bc, string, len);
422 }
423
424 static void put_s(ByteIOContext *bc, int64_t val){
425 if (val<=0) put_v(bc, -2*val );
426 else put_v(bc, 2*val-1);
427 }
428
429 static void put_vb(ByteIOContext *bc, uint64_t val){
430 int i;
431
432 for (i=8; val>>i; i+=8);
433
434 put_v(bc, i>>3);
435 for(i-=8; i>=0; i-=8)
436 put_byte(bc, (val>>i)&0xFF);
437 }
438
439 #ifdef TRACE
440 static inline void put_v_trace(ByteIOContext *bc, uint64_t v, char *file, char *func, int line){
441 printf("get_v %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
442
443 put_v(bc, v);
444 }
445
446 static inline void put_s_trace(ByteIOContext *bc, int64_t v, char *file, char *func, int line){
447 printf("get_s %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
448
449 put_s(bc, v);
450 }
451
452 static inline void put_vb_trace(ByteIOContext *bc, uint64_t v, char *file, char *func, int line){
453 printf("get_vb %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
454
455 put_vb(bc, v);
456 }
457 #define put_v(bc, v) put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
458 #define put_s(bc, v) put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
459 #define put_vb(bc, v) put_vb_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
460 #endif
461
462 static int put_packetheader(NUTContext *nut, ByteIOContext *bc, int max_size, int calculate_checksum)
463 {
464 put_flush_packet(bc);
465 nut->packet_start[2]= url_ftell(bc) - 8;
466 nut->written_packet_size = max_size;
467
468 /* packet header */
469 put_v(bc, nut->written_packet_size); /* forward ptr */
470
471 if(calculate_checksum)
472 init_checksum(bc, update_adler32, 0);
473
474 return 0;
475 }
476
477 /**
478 *
479 * must not be called more then once per packet
480 */
481 static int update_packetheader(NUTContext *nut, ByteIOContext *bc, int additional_size, int calculate_checksum){
482 int64_t start= nut->packet_start[2];
483 int64_t cur= url_ftell(bc);
484 int size= cur - start - get_length(nut->written_packet_size)/7 - 8;
485
486 if(calculate_checksum)
487 size += 4;
488
489 if(size != nut->written_packet_size){
490 int i;
491
492 assert( size <= nut->written_packet_size );
493
494 url_fseek(bc, start + 8, SEEK_SET);
495 for(i=get_length(size); i < get_length(nut->written_packet_size); i+=7)
496 put_byte(bc, 0x80);
497 put_v(bc, size);
498
499 url_fseek(bc, cur, SEEK_SET);
500 nut->written_packet_size= size; //FIXME may fail if multiple updates with differing sizes, as get_length may differ
501
502 if(calculate_checksum)
503 put_be32(bc, get_checksum(bc));
504 }
505
506 return 0;
507 }
508
509 static int nut_write_header(AVFormatContext *s)
510 {
511 NUTContext *nut = s->priv_data;
512 ByteIOContext *bc = &s->pb;
513 AVCodecContext *codec;
514 int i, j, tmp_time, tmp_flags,tmp_stream, tmp_mul, tmp_size, tmp_fields;
515
516 nut->avf= s;
517
518 nut->stream =
519 av_mallocz(sizeof(StreamContext)*s->nb_streams);
520
521
522 put_buffer(bc, ID_STRING, strlen(ID_STRING));
523 put_byte(bc, 0);
524 nut->packet_start[2]= url_ftell(bc);
525
526 /* main header */
527 put_be64(bc, MAIN_STARTCODE);
528 put_packetheader(nut, bc, 120+5*256, 1);
529 put_v(bc, 2); /* version */
530 put_v(bc, s->nb_streams);
531 put_v(bc, MAX_DISTANCE);
532 put_v(bc, MAX_SHORT_DISTANCE);
533
534 put_v(bc, nut->rate_num=1);
535 put_v(bc, nut->rate_den=2);
536 put_v(bc, nut->short_startcode=0x4EFE79);
537
538 build_frame_code(s);
539 assert(nut->frame_code['N'].flags == FLAG_INVALID);
540
541 tmp_time= tmp_flags= tmp_stream= tmp_mul= tmp_size= /*tmp_res=*/ INT_MAX;
542 for(i=0; i<256;){
543 tmp_fields=0;
544 tmp_size= 0;
545 if(tmp_time != nut->frame_code[i].timestamp_delta) tmp_fields=1;
546 if(tmp_mul != nut->frame_code[i].size_mul ) tmp_fields=2;
547 if(tmp_stream != nut->frame_code[i].stream_id_plus1) tmp_fields=3;
548 if(tmp_size != nut->frame_code[i].size_lsb ) tmp_fields=4;
549 // if(tmp_res != nut->frame_code[i].res ) tmp_fields=5;
550
551 tmp_time = nut->frame_code[i].timestamp_delta;
552 tmp_flags = nut->frame_code[i].flags;
553 tmp_stream= nut->frame_code[i].stream_id_plus1;
554 tmp_mul = nut->frame_code[i].size_mul;
555 tmp_size = nut->frame_code[i].size_lsb;
556 // tmp_res = nut->frame_code[i].res;
557
558 for(j=0; i<256; j++,i++){
559 if(nut->frame_code[i].timestamp_delta != tmp_time ) break;
560 if(nut->frame_code[i].flags != tmp_flags ) break;
561 if(nut->frame_code[i].stream_id_plus1 != tmp_stream) break;
562 if(nut->frame_code[i].size_mul != tmp_mul ) break;
563 if(nut->frame_code[i].size_lsb != tmp_size+j) break;
564 // if(nut->frame_code[i].res != tmp_res ) break;
565 }
566 if(j != tmp_mul - tmp_size) tmp_fields=6;
567
568 put_v(bc, tmp_flags);
569 put_v(bc, tmp_fields);
570 if(tmp_fields>0) put_s(bc, tmp_time);
571 if(tmp_fields>1) put_v(bc, tmp_mul);
572 if(tmp_fields>2) put_v(bc, tmp_stream);
573 if(tmp_fields>3) put_v(bc, tmp_size);
574 if(tmp_fields>4) put_v(bc, 0 /*tmp_res*/);
575 if(tmp_fields>5) put_v(bc, j);
576 }
577
578 update_packetheader(nut, bc, 0, 1);
579
580 /* stream headers */
581 for (i = 0; i < s->nb_streams; i++)
582 {
583 int nom, denom, ssize;
584
585 codec = s->streams[i]->codec;
586
587 put_be64(bc, STREAM_STARTCODE);
588 put_packetheader(nut, bc, 120 + codec->extradata_size, 1);
589 put_v(bc, i /*s->streams[i]->index*/);
590 switch(codec->codec_type){
591 case CODEC_TYPE_VIDEO: put_v(bc, 0); break;
592 case CODEC_TYPE_AUDIO: put_v(bc, 1); break;
593 // case CODEC_TYPE_TEXT : put_v(bc, 2); break;
594 case CODEC_TYPE_DATA : put_v(bc, 3); break;
595 default: return -1;
596 }
597 if (codec->codec_tag)
598 put_vb(bc, codec->codec_tag);
599 else if (codec->codec_type == CODEC_TYPE_VIDEO)
600 {
601 put_vb(bc, codec_get_bmp_tag(codec->codec_id));
602 }
603 else if (codec->codec_type == CODEC_TYPE_AUDIO)
604 {
605 put_vb(bc, codec_get_wav_tag(codec->codec_id));
606 }
607 else
608 put_vb(bc, 0);
609
610 ff_parse_specific_params(codec, &nom, &ssize, &denom);
611
612 nut->stream[i].rate_num= nom;
613 nut->stream[i].rate_den= denom;
614 av_set_pts_info(s->streams[i], 60, denom, nom);
615
616 put_v(bc, codec->bit_rate);
617 put_vb(bc, 0); /* no language code */
618 put_v(bc, nom);
619 put_v(bc, denom);
620 if(nom / denom < 1000)
621 nut->stream[i].msb_timestamp_shift = 7;
622 else
623 nut->stream[i].msb_timestamp_shift = 14;
624 put_v(bc, nut->stream[i].msb_timestamp_shift);
625 put_v(bc, codec->has_b_frames);
626 put_byte(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
627
628 if(codec->extradata_size){
629 put_v(bc, 1);
630 put_v(bc, codec->extradata_size);
631 put_buffer(bc, codec->extradata, codec->extradata_size);
632 }
633 put_v(bc, 0); /* end of codec specific headers */
634
635 switch(codec->codec_type)
636 {
637 case CODEC_TYPE_AUDIO:
638 put_v(bc, codec->sample_rate);
639 put_v(bc, 1);
640 put_v(bc, codec->channels);
641 break;
642 case CODEC_TYPE_VIDEO:
643 put_v(bc, codec->width);
644 put_v(bc, codec->height);
645 put_v(bc, codec->sample_aspect_ratio.num);
646 put_v(bc, codec->sample_aspect_ratio.den);
647 put_v(bc, 0); /* csp type -- unknown */
648 break;
649 default:
650 break;
651 }
652 update_packetheader(nut, bc, 0, 1);
653 }
654
655 /* info header */
656 put_be64(bc, INFO_STARTCODE);
657 put_packetheader(nut, bc, 30+strlen(s->author)+strlen(s->title)+
658 strlen(s->comment)+strlen(s->copyright)+strlen(LIBAVFORMAT_IDENT), 1);
659 if (s->author[0])
660 {
661 put_v(bc, 9); /* type */
662 put_str(bc, s->author);
663 }
664 if (s->title[0])
665 {
666 put_v(bc, 10); /* type */
667 put_str(bc, s->title);
668 }
669 if (s->comment[0])
670 {
671 put_v(bc, 11); /* type */
672 put_str(bc, s->comment);
673 }
674 if (s->copyright[0])
675 {
676 put_v(bc, 12); /* type */
677 put_str(bc, s->copyright);
678 }
679 /* encoder */
680 if(!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)){
681 put_v(bc, 13); /* type */
682 put_str(bc, LIBAVFORMAT_IDENT);
683 }
684
685 put_v(bc, 0); /* eof info */
686 update_packetheader(nut, bc, 0, 1);
687
688 put_flush_packet(bc);
689
690 return 0;
691 }
692
693 static int64_t lsb2full(StreamContext *stream, int64_t lsb){
694 int64_t mask = (1<<stream->msb_timestamp_shift)-1;
695 int64_t delta= stream->last_pts - mask/2;
696 return ((lsb - delta)&mask) + delta;
697 }
698
699 static int nut_write_packet(AVFormatContext *s, AVPacket *pkt)
700 {
701 NUTContext *nut = s->priv_data;
702 StreamContext *stream= &nut->stream[pkt->stream_index];
703 ByteIOContext *bc = &s->pb;
704 int key_frame = 0, full_pts=0;
705 AVCodecContext *enc;
706 int64_t coded_pts;
707 int frame_type, best_length, frame_code, flags, i, size_mul, size_lsb, time_delta;
708 const int64_t frame_start= url_ftell(bc);
709 int64_t pts= pkt->pts;
710 int size= pkt->size;
711 int stream_index= pkt->stream_index;
712
713 enc = s->streams[stream_index]->codec;
714 key_frame = !!(pkt->flags & PKT_FLAG_KEY);
715
716 frame_type=0;
717 if(frame_start + size + 20 - FFMAX(nut->packet_start[1], nut->packet_start[2]) > MAX_DISTANCE)
718 frame_type=2;
719 if(key_frame && !stream->last_key_frame)
720 frame_type=2;
721
722 if(frame_type>1){
723 int64_t global_ts= av_rescale(pts, stream->rate_den*(int64_t)nut->rate_num, stream->rate_num*(int64_t)nut->rate_den);
724 reset(s, global_ts);
725 put_be64(bc, KEYFRAME_STARTCODE);
726 put_v(bc, global_ts);
727 }
728 assert(stream->last_pts != AV_NOPTS_VALUE);
729 coded_pts = pts & ((1<<stream->msb_timestamp_shift)-1);
730 if(lsb2full(stream, coded_pts) != pts)
731 full_pts=1;
732
733 if(full_pts)
734 coded_pts= pts + (1<<stream->msb_timestamp_shift);
735
736 best_length=INT_MAX;
737 frame_code= -1;
738 for(i=0; i<256; i++){
739 int stream_id_plus1= nut->frame_code[i].stream_id_plus1;
740 int fc_key_frame;
741 int length=0;
742 size_mul= nut->frame_code[i].size_mul;
743 size_lsb= nut->frame_code[i].size_lsb;
744 time_delta= nut->frame_code[i].timestamp_delta;
745 flags= nut->frame_code[i].flags;
746
747 assert(size_mul > size_lsb);
748
749 if(stream_id_plus1 == 0) length+= get_length(stream_index);
750 else if(stream_id_plus1 - 1 != stream_index)
751 continue;
752 fc_key_frame= !!(flags & FLAG_KEY_FRAME);
753
754 assert(key_frame==0 || key_frame==1);
755 if(fc_key_frame != key_frame)
756 continue;
757
758 if(flags & FLAG_DATA_SIZE){
759 if(size % size_mul != size_lsb)
760 continue;
761 length += get_length(size / size_mul);
762 }else if(size != size_lsb)
763 continue;
764
765 if(full_pts && time_delta)
766 continue;
767
768 if(!time_delta){
769 length += get_length(coded_pts);
770 }else{
771 if(time_delta != pts - stream->last_pts)
772 continue;
773 }
774
775 if(length < best_length){
776 best_length= length;
777 frame_code=i;
778 }
779 // av_log(s, AV_LOG_DEBUG, "%d %d %d %d %d %d %d %d %d %d\n", key_frame, frame_type, full_pts, size, stream_index, flags, size_mul, size_lsb, stream_id_plus1, length);
780 }
781
782 assert(frame_code != -1);
783 flags= nut->frame_code[frame_code].flags;
784 size_mul= nut->frame_code[frame_code].size_mul;
785 size_lsb= nut->frame_code[frame_code].size_lsb;
786 time_delta= nut->frame_code[frame_code].timestamp_delta;
787 #ifdef TRACE
788 best_length /= 7;
789 best_length ++; //frame_code
790 if(frame_type==2){
791 best_length += 8; // startcode
792 }
793 av_log(s, AV_LOG_DEBUG, "kf:%d ft:%d pt:%d fc:%2X len:%2d size:%d stream:%d flag:%d mul:%d lsb:%d s+1:%d pts_delta:%d pts:%lld fs:%lld\n", key_frame, frame_type, full_pts ? 1 : 0, frame_code, best_length, size, stream_index, flags, size_mul, size_lsb, nut->frame_code[frame_code].stream_id_plus1,(int)(pts - stream->last_pts), pts, frame_start);
794 // av_log(s, AV_LOG_DEBUG, "%d %d %d\n", stream->lru_pts_delta[0], stream->lru_pts_delta[1], stream->lru_pts_delta[2]);
795 #endif
796
797 assert(frame_type != 1); //short startcode not implemented yet
798 put_byte(bc, frame_code);
799
800 if(nut->frame_code[frame_code].stream_id_plus1 == 0)
801 put_v(bc, stream_index);
802 if (!time_delta){
803 put_v(bc, coded_pts);
804 }
805 if(flags & FLAG_DATA_SIZE)
806 put_v(bc, size / size_mul);
807 else
808 assert(size == size_lsb);
809 if(size > MAX_DISTANCE){
810 assert(frame_type > 1);
811 }
812
813 put_buffer(bc, pkt->data, size);
814
815 update(nut, stream_index, frame_start, frame_type, frame_code, key_frame, size, pts);
816
817 return 0;
818 }
819
820 static int nut_write_trailer(AVFormatContext *s)
821 {
822 NUTContext *nut = s->priv_data;
823 ByteIOContext *bc = &s->pb;
824
825 #if 0
826 int i;
827
828 /* WRITE INDEX */
829
830 for (i = 0; s->nb_streams; i++)
831 {
832 put_be64(bc, INDEX_STARTCODE);
833 put_packetheader(nut, bc, 64, 1);
834 put_v(bc, s->streams[i]->id);
835 put_v(bc, ...);
836 update_packetheader(nut, bc, 0, 1);
837 }
838 #endif
839
840 put_flush_packet(bc);
841
842 av_freep(&nut->stream);
843
844 return 0;
845 }
846 #endif //CONFIG_MUXERS
847
848 static int nut_probe(AVProbeData *p)
849 {
850 int i;
851 uint64_t code= 0xff;
852
853 for (i = 0; i < p->buf_size; i++) {
854 code = (code << 8) | p->buf[i];
855 if (code == MAIN_STARTCODE)
856 return AVPROBE_SCORE_MAX;
857 }
858 return 0;
859 }
860
861 static int decode_main_header(NUTContext *nut){
862 AVFormatContext *s= nut->avf;
863 ByteIOContext *bc = &s->pb;
864 uint64_t tmp;
865 int i, j, tmp_stream, tmp_mul, tmp_time, tmp_size, count, tmp_res;
866
867 get_packetheader(nut, bc, 1);
868
869 tmp = get_v(bc);
870 if (tmp != 2){
871 av_log(s, AV_LOG_ERROR, "bad version (%Ld)\n", tmp);
872 return -1;
873 }
874
875 nut->stream_count = get_v(bc);
876 if(nut->stream_count > MAX_STREAMS){
877 av_log(s, AV_LOG_ERROR, "too many streams\n");
878 return -1;
879 }
880 nut->max_distance = get_v(bc);
881 nut->max_short_distance = get_v(bc);
882 nut->rate_num= get_v(bc);
883 nut->rate_den= get_v(bc);
884 nut->short_startcode= get_v(bc);
885 if(nut->short_startcode>>16 != 'N'){
886 av_log(s, AV_LOG_ERROR, "invalid short startcode %X\n", nut->short_startcode);
887 return -1;
888 }
889
890 for(i=0; i<256;){
891 int tmp_flags = get_v(bc);
892 int tmp_fields= get_v(bc);
893 if(tmp_fields>0) tmp_time = get_s(bc);
894 if(tmp_fields>1) tmp_mul = get_v(bc);
895 if(tmp_fields>2) tmp_stream= get_v(bc);
896 if(tmp_fields>3) tmp_size = get_v(bc);
897 else tmp_size = 0;
898 if(tmp_fields>4) tmp_res = get_v(bc);
899 else tmp_res = 0;
900 if(tmp_fields>5) count = get_v(bc);
901 else count = tmp_mul - tmp_size;
902
903 while(tmp_fields-- > 6)
904 get_v(bc);
905
906 if(count == 0 || i+count > 256){
907 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
908 return -1;
909 }
910 if(tmp_stream > nut->stream_count + 1){
911 av_log(s, AV_LOG_ERROR, "illegal stream number\n");
912 return -1;
913 }
914
915 for(j=0; j<count; j++,i++){
916 nut->frame_code[i].flags = tmp_flags ;
917 nut->frame_code[i].timestamp_delta = tmp_time ;
918 nut->frame_code[i].stream_id_plus1 = tmp_stream;
919 nut->frame_code[i].size_mul = tmp_mul ;
920 nut->frame_code[i].size_lsb = tmp_size+j;
921 nut->frame_code[i].reserved_count = tmp_res ;
922 }
923 }
924 if(nut->frame_code['N'].flags != FLAG_INVALID){
925 av_log(s, AV_LOG_ERROR, "illegal frame_code table\n");
926 return -1;
927 }
928
929 if(check_checksum(bc)){
930 av_log(s, AV_LOG_ERROR, "Main header checksum mismatch\n");
931 return -1;
932 }
933
934 return 0;
935 }
936
937 static int decode_stream_header(NUTContext *nut){
938 AVFormatContext *s= nut->avf;
939 ByteIOContext *bc = &s->pb;
940 int class, nom, denom, stream_id;
941 uint64_t tmp;
942 AVStream *st;
943
944 get_packetheader(nut, bc, 1);
945 stream_id= get_v(bc);
946 if(stream_id >= nut->stream_count || s->streams[stream_id])
947 return -1;
948
949 st = av_new_stream(s, stream_id);
950 if (!st)
951 return AVERROR_NOMEM;
952
953 class = get_v(bc);
954 tmp = get_vb(bc);
955 st->codec->codec_tag= tmp;
956 switch(class)
957 {
958 case 0:
959 st->codec->codec_type = CODEC_TYPE_VIDEO;
960 st->codec->codec_id = codec_get_bmp_id(tmp);
961 if (st->codec->codec_id == CODEC_ID_NONE)
962 av_log(s, AV_LOG_ERROR, "Unknown codec?!\n");
963 break;
964 case 1:
965 case 32: //compatibility
966 st->codec->codec_type = CODEC_TYPE_AUDIO;
967 st->codec->codec_id = codec_get_wav_id(tmp);
968 if (st->codec->codec_id == CODEC_ID_NONE)
969 av_log(s, AV_LOG_ERROR, "Unknown codec?!\n");
970 break;
971 case 2:
972 // st->codec->codec_type = CODEC_TYPE_TEXT;
973 // break;
974 case 3:
975 st->codec->codec_type = CODEC_TYPE_DATA;
976 break;
977 default:
978 av_log(s, AV_LOG_ERROR, "Unknown stream class (%d)\n", class);
979 return -1;
980 }
981 s->bit_rate += get_v(bc);
982 get_vb(bc); /* language code */
983 nom = get_v(bc);
984 denom = get_v(bc);
985 nut->stream[stream_id].msb_timestamp_shift = get_v(bc);
986 st->codec->has_b_frames=
987 nut->stream[stream_id].decode_delay= get_v(bc);
988 get_byte(bc); /* flags */
989
990 /* codec specific data headers */
991 while(get_v(bc) != 0){
992 st->codec->extradata_size= get_v(bc);
993 if((unsigned)st->codec->extradata_size > (1<<30))
994 return -1;
995 st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
996 get_buffer(bc, st->codec->extradata, st->codec->extradata_size);
997 // url_fskip(bc, get_v(bc));
998 }
999
1000 if (st->codec->codec_type == CODEC_TYPE_VIDEO) /* VIDEO */
1001 {
1002 st->codec->width = get_v(bc);
1003 st->codec->height = get_v(bc);
1004 st->codec->sample_aspect_ratio.num= get_v(bc);
1005 st->codec->sample_aspect_ratio.den= get_v(bc);
1006 get_v(bc); /* csp type */
1007 }
1008 if (st->codec->codec_type == CODEC_TYPE_AUDIO) /* AUDIO */
1009 {
1010 st->codec->sample_rate = get_v(bc);
1011 get_v(bc); // samplerate_den
1012 st->codec->channels = get_v(bc);
1013 }
1014 if(check_checksum(bc)){
1015 av_log(s, AV_LOG_ERROR, "Stream header %d checksum mismatch\n", stream_id);
1016 return -1;
1017 }
1018 av_set_pts_info(s->streams[stream_id], 60, denom, nom);
1019 nut->stream[stream_id].rate_num= nom;
1020 nut->stream[stream_id].rate_den= denom;
1021 return 0;
1022 }
1023
1024 static int decode_info_header(NUTContext *nut){
1025 AVFormatContext *s= nut->avf;
1026 ByteIOContext *bc = &s->pb;
1027
1028 get_packetheader(nut, bc, 1);
1029
1030 for(;;){
1031 int id= get_v(bc);
1032 char *name, *type, custom_name[256], custom_type[256];
1033
1034 if(!id)
1035 break;
1036 else if(id >= sizeof(info_table)/sizeof(info_table[0])){
1037 av_log(s, AV_LOG_ERROR, "info id is too large %d %d\n", id, sizeof(info_table)/sizeof(info_table[0]));
1038 return -1;
1039 }
1040
1041 type= info_table[id][1];
1042 name= info_table[id][0];
1043 //av_log(s, AV_LOG_DEBUG, "%d %s %s\n", id, type, name);
1044
1045 if(!type){
1046 get_str(bc, custom_type, sizeof(custom_type));
1047 type= custom_type;
1048 }
1049 if(!name){
1050 get_str(bc, custom_name, sizeof(custom_name));
1051 name= custom_name;
1052 }
1053
1054 if(!strcmp(type, "v")){
1055 get_v(bc);
1056 }else{
1057 if(!strcmp(name, "Author"))
1058 get_str(bc, s->author, sizeof(s->author));
1059 else if(!strcmp(name, "Title"))
1060 get_str(bc, s->title, sizeof(s->title));
1061 else if(!strcmp(name, "Copyright"))
1062 get_str(bc, s->copyright, sizeof(s->copyright));
1063 else if(!strcmp(name, "Description"))
1064 get_str(bc, s->comment, sizeof(s->comment));
1065 else
1066 get_str(bc, NULL, 0);
1067 }
1068 }
1069 if(check_checksum(bc)){
1070 av_log(s, AV_LOG_ERROR, "Info header checksum mismatch\n");
1071 return -1;
1072 }
1073 return 0;
1074 }
1075
1076 static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
1077 {
1078 NUTContext *nut = s->priv_data;
1079 ByteIOContext *bc = &s->pb;
1080 int64_t pos;
1081 int inited_stream_count;
1082
1083 nut->avf= s;
1084
1085 /* main header */
1086 pos=0;
1087 for(;;){
1088 pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
1089 if (pos<0){
1090 av_log(s, AV_LOG_ERROR, "no main startcode found\n");
1091 return -1;
1092 }
1093 if(decode_main_header(nut) >= 0)
1094 break;
1095 }
1096
1097
1098 s->bit_rate = 0;
1099
1100 nut->stream = av_malloc(sizeof(StreamContext)*nut->stream_count);
1101
1102 /* stream headers */
1103 pos=0;
1104 for(inited_stream_count=0; inited_stream_count < nut->stream_count;){
1105 pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
1106 if (pos<0+1){
1107 av_log(s, AV_LOG_ERROR, "not all stream headers found\n");
1108 return -1;
1109 }
1110 if(decode_stream_header(nut) >= 0)
1111 inited_stream_count++;
1112 }
1113
1114 /* info headers */
1115 pos=0;
1116 for(;;){
1117 uint64_t startcode= find_any_startcode(bc, pos);
1118 pos= url_ftell(bc);
1119
1120 if(startcode==0){
1121 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
1122 return -1;
1123 }else if(startcode == KEYFRAME_STARTCODE){
1124 nut->next_startcode= startcode;
1125 break;
1126 }else if(startcode != INFO_STARTCODE){
1127 continue;
1128 }
1129
1130 decode_info_header(nut);
1131 }
1132
1133 return 0;
1134 }
1135
1136 static int decode_frame_header(NUTContext *nut, int *key_frame_ret, int64_t *pts_ret, int *stream_id_ret, int frame_code, int frame_type, int64_t frame_start){
1137 AVFormatContext *s= nut->avf;
1138 StreamContext *stream;
1139 ByteIOContext *bc = &s->pb;
1140 int size, flags, size_mul, size_lsb, stream_id, time_delta;
1141 int64_t pts = 0;
1142
1143 if(frame_type < 2 && frame_start - nut->packet_start[2] > nut->max_distance){
1144 av_log(s, AV_LOG_ERROR, "last frame must have been damaged\n");
1145 return -1;
1146 }
1147
1148 if(frame_type)
1149 nut->packet_start[ frame_type ]= frame_start; //otherwise 1 goto 1 may happen
1150
1151 flags= nut->frame_code[frame_code].flags;
1152 size_mul= nut->frame_code[frame_code].size_mul;
1153 size_lsb= nut->frame_code[frame_code].size_lsb;
1154 stream_id= nut->frame_code[frame_code].stream_id_plus1 - 1;
1155 time_delta= nut->frame_code[frame_code].timestamp_delta;
1156
1157 if(stream_id==-1)
1158 stream_id= get_v(bc);
1159 if(stream_id >= s->nb_streams){
1160 av_log(s, AV_LOG_ERROR, "illegal stream_id\n");
1161 return -1;
1162 }
1163 stream= &nut->stream[stream_id];
1164
1165 // av_log(s, AV_LOG_DEBUG, "ft:%d ppts:%d %d %d\n", frame_type, stream->lru_pts_delta[0], stream->lru_pts_delta[1], stream->lru_pts_delta[2]);
1166
1167 *key_frame_ret= !!(flags & FLAG_KEY_FRAME);
1168
1169 if(!time_delta){
1170 int64_t mask = (1<<stream->msb_timestamp_shift)-1;
1171 pts= get_v(bc);
1172 if(pts > mask){
1173 pts -= mask+1;
1174 }else{
1175 if(stream->last_pts == AV_NOPTS_VALUE){
1176 av_log(s, AV_LOG_ERROR, "no reference pts available\n");
1177 return -1;
1178 }
1179 pts= lsb2full(stream, pts);
1180 }
1181 }else{
1182 if(stream->last_pts == AV_NOPTS_VALUE){
1183 av_log(s, AV_LOG_ERROR, "no reference pts available\n");
1184 return -1;
1185 }
1186 pts= stream->last_pts + time_delta;
1187 }
1188
1189 if(*key_frame_ret){
1190 // av_log(s, AV_LOG_DEBUG, "stream:%d start:%lld pts:%lld length:%lld\n",stream_id, frame_start, av_pts, frame_start - nut->stream[stream_id].last_sync_pos);
1191 av_add_index_entry(
1192 s->streams[stream_id],
1193 frame_start,
1194 pts,
1195 frame_start - nut->stream[stream_id].last_sync_pos,
1196 AVINDEX_KEYFRAME);
1197 nut->stream[stream_id].last_sync_pos= frame_start;
1198 // assert(nut->packet_start == frame_start);
1199 }
1200
1201 assert(size_mul > size_lsb);
1202 size= size_lsb;
1203 if(flags & FLAG_DATA_SIZE)
1204 size+= size_mul*get_v(bc);
1205
1206 #ifdef TRACE
1207 av_log(s, AV_LOG_DEBUG, "fs:%lld fc:%d ft:%d kf:%d pts:%lld size:%d mul:%d lsb:%d flags:%d delta:%d\n", frame_start, frame_code, frame_type, *key_frame_ret, pts, size, size_mul, size_lsb, flags, time_delta);
1208 #endif
1209
1210 if(frame_type==0 && url_ftell(bc) - nut->packet_start[2] + size > nut->max_distance){
1211 av_log(s, AV_LOG_ERROR, "frame size too large\n");
1212 return -1;
1213 }
1214
1215 *stream_id_ret = stream_id;
1216 *pts_ret = pts;
1217
1218 update(nut, stream_id, frame_start, frame_type, frame_code, *key_frame_ret, size, pts);
1219
1220 return size;
1221 }
1222
1223 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code, int frame_type, int64_t frame_start){
1224 AVFormatContext *s= nut->avf;
1225 ByteIOContext *bc = &s->pb;
1226 int size, stream_id, key_frame, discard;
1227 int64_t pts, last_IP_pts;
1228
1229 size= decode_frame_header(nut, &key_frame, &pts, &stream_id, frame_code, frame_type, frame_start);
1230 if(size < 0)
1231 return -1;
1232
1233 discard= s->streams[ stream_id ]->discard;
1234 last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
1235 if( (discard >= AVDISCARD_NONKEY && !key_frame)
1236 ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
1237 || discard >= AVDISCARD_ALL){
1238 url_fskip(bc, size);
1239 return 1;
1240 }
1241
1242 av_get_packet(bc, pkt, size);
1243 pkt->stream_index = stream_id;
1244 if (key_frame)
1245 pkt->flags |= PKT_FLAG_KEY;
1246 pkt->pts = pts;
1247
1248 return 0;
1249 }
1250
1251 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
1252 {
1253 NUTContext *nut = s->priv_data;
1254 ByteIOContext *bc = &s->pb;
1255 int i, frame_code=0, ret;
1256
1257 for(;;){
1258 int64_t pos= url_ftell(bc);
1259 int frame_type= 0;
1260 uint64_t tmp= nut->next_startcode;
1261 nut->next_startcode=0;
1262
1263 if (url_feof(bc))
1264 return -1;
1265
1266 if(tmp){
1267 pos-=8;
1268 }else{
1269 frame_code = get_byte(bc);
1270 if(frame_code == 'N'){
1271 tmp= frame_code;
1272 for(i=1; i<8; i++)
1273 tmp = (tmp<<8) + get_byte(bc);
1274 }
1275 }
1276 switch(tmp){
1277 case MAIN_STARTCODE:
1278 case STREAM_STARTCODE:
1279 case INDEX_STARTCODE:
1280 get_packetheader(nut, bc, 0);
1281 assert(nut->packet_start[2] == pos);
1282 url_fseek(bc, nut->written_packet_size, SEEK_CUR);
1283 break;
1284 case INFO_STARTCODE:
1285 if(decode_info_header(nut)<0)
1286 goto resync;
1287 break;
1288 case KEYFRAME_STARTCODE:
1289 frame_type = 2;
1290 reset(s, get_v(bc));
1291 frame_code = get_byte(bc);
1292 case 0:
1293 ret= decode_frame(nut, pkt, frame_code, frame_type, pos);
1294 if(ret==0)
1295 return 0;
1296 else if(ret==1) //ok but discard packet
1297 break;
1298 default:
1299 resync:
1300 av_log(s, AV_LOG_DEBUG, "syncing from %lld\n", nut->packet_start[2]+1);
1301 tmp= find_any_startcode(bc, nut->packet_start[2]+1);
1302 if(tmp==0)
1303 return -1;
1304 av_log(s, AV_LOG_DEBUG, "sync\n");
1305 nut->next_startcode= tmp;
1306 }
1307 }
1308 }
1309
1310 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
1311 NUTContext *nut = s->priv_data;
1312 StreamContext *stream;
1313 ByteIOContext *bc = &s->pb;
1314 int64_t pos, pts;
1315 uint64_t code;
1316 int frame_code,step, stream_id, i,size, key_frame;
1317 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%lld,%lld)\n", stream_index, *pos_arg, pos_limit);
1318
1319 if(*pos_arg < 0)
1320 return AV_NOPTS_VALUE;
1321
1322 pos= *pos_arg;
1323 step= FFMIN(16*1024, pos);
1324 do{
1325 pos-= step;
1326 code= find_any_startcode(bc, pos);
1327
1328 if(code && url_ftell(bc) - 8 <= *pos_arg)
1329 break;
1330 step= FFMIN(2*step, pos);
1331 }while(step);
1332
1333 if(!code) //nothing found, not even after pos_arg
1334 return AV_NOPTS_VALUE;
1335
1336 url_fseek(bc, -8, SEEK_CUR);
1337 for(i=0; i<s->nb_streams; i++)
1338 nut->stream[i].last_sync_pos= url_ftell(bc);
1339
1340 for(;;){
1341 int frame_type=0;
1342 int64_t pos= url_ftell(bc);
1343 uint64_t tmp=0;
1344
1345 if(pos > pos_limit || url_feof(bc))
1346 return AV_NOPTS_VALUE;
1347
1348 frame_code = get_byte(bc);
1349 if(frame_code == 'N'){
1350 tmp= frame_code;
1351 for(i=1; i<8; i++)
1352 tmp = (tmp<<8) + get_byte(bc);
1353 }
1354 //av_log(s, AV_LOG_DEBUG, "before switch %llX at=%lld\n", tmp, pos);
1355
1356 switch(tmp){
1357 case MAIN_STARTCODE:
1358 case STREAM_STARTCODE:
1359 case INDEX_STARTCODE:
1360 case INFO_STARTCODE:
1361 get_packetheader(nut, bc, 0);
1362 assert(nut->packet_start[2]==pos);
1363 url_fseek(bc, nut->written_packet_size, SEEK_CUR);
1364 break;
1365 case KEYFRAME_STARTCODE:
1366 frame_type=2;
1367 reset(s, get_v(bc));
1368 frame_code = get_byte(bc);
1369 case 0:
1370 size= decode_frame_header(nut, &key_frame, &pts, &stream_id, frame_code, frame_type, pos);
1371 if(size < 0)
1372 goto resync;
1373
1374 stream= &nut->stream[stream_id];
1375 if(stream_id != stream_index || !key_frame || pos < *pos_arg){
1376 url_fseek(bc, size, SEEK_CUR);
1377 break;
1378 }
1379
1380 *pos_arg= pos;
1381 return pts;
1382 default:
1383 resync:
1384 av_log(s, AV_LOG_DEBUG, "syncing from %lld\n", nut->packet_start[2]+1);
1385 if(!find_any_startcode(bc, nut->packet_start[2]+1))
1386 return AV_NOPTS_VALUE;
1387
1388 url_fseek(bc, -8, SEEK_CUR);
1389 }
1390 }
1391 return AV_NOPTS_VALUE;
1392 }
1393
1394 static int nut_read_seek(AVFormatContext *s, int stream_index, int64_t target_ts, int flags){
1395 // NUTContext *nut = s->priv_data;
1396 int64_t pos;
1397
1398 if(av_seek_frame_binary(s, stream_index, target_ts, flags) < 0)
1399 return -1;
1400
1401 pos= url_ftell(&s->pb);
1402 nut_read_timestamp(s, stream_index, &pos, pos-1);
1403
1404 return 0;
1405 }
1406
1407 static int nut_read_close(AVFormatContext *s)
1408 {
1409 NUTContext *nut = s->priv_data;
1410 int i;
1411
1412 for(i=0;i<s->nb_streams;i++) {
1413 av_freep(&s->streams[i]->codec->extradata);
1414 }
1415 av_freep(&nut->stream);
1416
1417 return 0;
1418 }
1419
1420 static AVInputFormat nut_iformat = {
1421 "nut",
1422 "nut format",
1423 sizeof(NUTContext),
1424 nut_probe,
1425 nut_read_header,
1426 nut_read_packet,
1427 nut_read_close,
1428 nut_read_seek,
1429 nut_read_timestamp,
1430 .extensions = "nut",
1431 };
1432
1433 #ifdef CONFIG_MUXERS
1434 static AVOutputFormat nut_oformat = {
1435 "nut",
1436 "nut format",
1437 "video/x-nut",
1438 "nut",
1439 sizeof(NUTContext),
1440 #ifdef CONFIG_LIBVORBIS
1441 CODEC_ID_VORBIS,
1442 #elif defined(CONFIG_MP3LAME)
1443 CODEC_ID_MP3,
1444 #else
1445 CODEC_ID_MP2, /* AC3 needs liba52 decoder */
1446 #endif
1447 CODEC_ID_MPEG4,
1448 nut_write_header,
1449 nut_write_packet,
1450 nut_write_trailer,
1451 .flags = AVFMT_GLOBALHEADER,
1452 };
1453 #endif //CONFIG_MUXERS
1454
1455 int nut_init(void)
1456 {
1457 av_register_input_format(&nut_iformat);
1458 #ifdef CONFIG_MUXERS
1459 av_register_output_format(&nut_oformat);
1460 #endif //CONFIG_MUXERS
1461 return 0;
1462 }