100l (forgoten seeking functions)
[libav.git] / libavformat / ffm.c
1 /*
2 * FFM (ffserver live feed) encoder and decoder
3 * Copyright (c) 2001 Fabrice Bellard.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19 #include "avformat.h"
20 #include <unistd.h>
21
22 /* The FFM file is made of blocks of fixed size */
23 #define FFM_HEADER_SIZE 14
24 #define PACKET_ID 0x666d
25
26 /* each packet contains frames (which can span several packets */
27 #define FRAME_HEADER_SIZE 8
28 #define FLAG_KEY_FRAME 0x01
29
30 typedef struct FFMStream {
31 int64_t pts;
32 } FFMStream;
33
34 enum {
35 READ_HEADER,
36 READ_DATA,
37 };
38
39 typedef struct FFMContext {
40 /* only reading mode */
41 offset_t write_index, file_size;
42 int read_state;
43 uint8_t header[FRAME_HEADER_SIZE];
44
45 /* read and write */
46 int first_packet; /* true if first packet, needed to set the discontinuity tag */
47 int packet_size;
48 int frame_offset;
49 int64_t pts;
50 uint8_t *packet_ptr, *packet_end;
51 uint8_t packet[FFM_PACKET_SIZE];
52 } FFMContext;
53
54 static int64_t get_pts(AVFormatContext *s, offset_t pos);
55
56 /* disable pts hack for testing */
57 int ffm_nopts = 0;
58
59 #ifdef CONFIG_ENCODERS
60 static void flush_packet(AVFormatContext *s)
61 {
62 FFMContext *ffm = s->priv_data;
63 int fill_size, h;
64 ByteIOContext *pb = &s->pb;
65
66 fill_size = ffm->packet_end - ffm->packet_ptr;
67 memset(ffm->packet_ptr, 0, fill_size);
68
69 if (url_ftell(pb) % ffm->packet_size)
70 av_abort();
71
72 /* put header */
73 put_be16(pb, PACKET_ID);
74 put_be16(pb, fill_size);
75 put_be64(pb, ffm->pts);
76 h = ffm->frame_offset;
77 if (ffm->first_packet)
78 h |= 0x8000;
79 put_be16(pb, h);
80 put_buffer(pb, ffm->packet, ffm->packet_end - ffm->packet);
81
82 /* prepare next packet */
83 ffm->frame_offset = 0; /* no key frame */
84 ffm->pts = 0; /* no pts */
85 ffm->packet_ptr = ffm->packet;
86 ffm->first_packet = 0;
87 }
88
89 /* 'first' is true if first data of a frame */
90 static void ffm_write_data(AVFormatContext *s,
91 const uint8_t *buf, int size,
92 int64_t pts, int first)
93 {
94 FFMContext *ffm = s->priv_data;
95 int len;
96
97 if (first && ffm->frame_offset == 0)
98 ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
99 if (first && ffm->pts == 0)
100 ffm->pts = pts;
101
102 /* write as many packets as needed */
103 while (size > 0) {
104 len = ffm->packet_end - ffm->packet_ptr;
105 if (len > size)
106 len = size;
107 memcpy(ffm->packet_ptr, buf, len);
108
109 ffm->packet_ptr += len;
110 buf += len;
111 size -= len;
112 if (ffm->packet_ptr >= ffm->packet_end) {
113 /* special case : no pts in packet : we leave the current one */
114 if (ffm->pts == 0)
115 ffm->pts = pts;
116
117 flush_packet(s);
118 }
119 }
120 }
121
122 static int ffm_write_header(AVFormatContext *s)
123 {
124 FFMContext *ffm = s->priv_data;
125 AVStream *st;
126 FFMStream *fst;
127 ByteIOContext *pb = &s->pb;
128 AVCodecContext *codec;
129 int bit_rate, i;
130
131 ffm->packet_size = FFM_PACKET_SIZE;
132
133 /* header */
134 put_tag(pb, "FFM1");
135 put_be32(pb, ffm->packet_size);
136 /* XXX: store write position in other file ? */
137 put_be64(pb, ffm->packet_size); /* current write position */
138
139 put_be32(pb, s->nb_streams);
140 bit_rate = 0;
141 for(i=0;i<s->nb_streams;i++) {
142 st = s->streams[i];
143 bit_rate += st->codec.bit_rate;
144 }
145 put_be32(pb, bit_rate);
146
147 /* list of streams */
148 for(i=0;i<s->nb_streams;i++) {
149 st = s->streams[i];
150 fst = av_mallocz(sizeof(FFMStream));
151 if (!fst)
152 goto fail;
153 av_set_pts_info(st, 64, 1, 1000000);
154 st->priv_data = fst;
155
156 codec = &st->codec;
157 /* generic info */
158 put_be32(pb, codec->codec_id);
159 put_byte(pb, codec->codec_type);
160 put_be32(pb, codec->bit_rate);
161 put_be32(pb, st->quality);
162 put_be32(pb, codec->flags);
163 /* specific info */
164 switch(codec->codec_type) {
165 case CODEC_TYPE_VIDEO:
166 put_be32(pb, codec->frame_rate_base);
167 put_be32(pb, codec->frame_rate);
168 put_be16(pb, codec->width);
169 put_be16(pb, codec->height);
170 put_be16(pb, codec->gop_size);
171 put_byte(pb, codec->qmin);
172 put_byte(pb, codec->qmax);
173 put_byte(pb, codec->max_qdiff);
174 put_be16(pb, (int) (codec->qcompress * 10000.0));
175 put_be16(pb, (int) (codec->qblur * 10000.0));
176 put_be32(pb, codec->bit_rate_tolerance);
177 put_strz(pb, codec->rc_eq);
178 put_be32(pb, codec->rc_max_rate);
179 put_be32(pb, codec->rc_min_rate);
180 put_be32(pb, codec->rc_buffer_size);
181 put_be64_double(pb, codec->i_quant_factor);
182 put_be64_double(pb, codec->b_quant_factor);
183 put_be64_double(pb, codec->i_quant_offset);
184 put_be64_double(pb, codec->b_quant_offset);
185 put_be32(pb, codec->dct_algo);
186 break;
187 case CODEC_TYPE_AUDIO:
188 put_be32(pb, codec->sample_rate);
189 put_le16(pb, codec->channels);
190 put_le16(pb, codec->frame_size);
191 break;
192 default:
193 return -1;
194 }
195 /* hack to have real time */
196 if (ffm_nopts)
197 fst->pts = 0;
198 else
199 fst->pts = av_gettime();
200 }
201
202 /* flush until end of block reached */
203 while ((url_ftell(pb) % ffm->packet_size) != 0)
204 put_byte(pb, 0);
205
206 put_flush_packet(pb);
207
208 /* init packet mux */
209 ffm->packet_ptr = ffm->packet;
210 ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
211 assert(ffm->packet_end >= ffm->packet);
212 ffm->frame_offset = 0;
213 ffm->pts = 0;
214 ffm->first_packet = 1;
215
216 return 0;
217 fail:
218 for(i=0;i<s->nb_streams;i++) {
219 st = s->streams[i];
220 av_freep(&st->priv_data);
221 }
222 return -1;
223 }
224
225 static int ffm_write_packet(AVFormatContext *s, AVPacket *pkt)
226 {
227 AVStream *st = s->streams[pkt->stream_index];
228 FFMStream *fst = st->priv_data;
229 int64_t pts;
230 uint8_t header[FRAME_HEADER_SIZE];
231 int duration;
232 int size= pkt->size;
233
234 //XXX/FIXME use duration from pkt
235 if (st->codec.codec_type == CODEC_TYPE_AUDIO) {
236 duration = ((float)st->codec.frame_size / st->codec.sample_rate * 1000000.0);
237 } else {
238 duration = (1000000.0 * st->codec.frame_rate_base / (float)st->codec.frame_rate);
239 }
240
241 pts = fst->pts;
242 /* packet size & key_frame */
243 header[0] = pkt->stream_index;
244 header[1] = 0;
245 if (pkt->flags & PKT_FLAG_KEY)
246 header[1] |= FLAG_KEY_FRAME;
247 header[2] = (size >> 16) & 0xff;
248 header[3] = (size >> 8) & 0xff;
249 header[4] = size & 0xff;
250 header[5] = (duration >> 16) & 0xff;
251 header[6] = (duration >> 8) & 0xff;
252 header[7] = duration & 0xff;
253 ffm_write_data(s, header, FRAME_HEADER_SIZE, pts, 1);
254 ffm_write_data(s, pkt->data, size, pts, 0);
255
256 fst->pts += duration;
257 return 0;
258 }
259
260 static int ffm_write_trailer(AVFormatContext *s)
261 {
262 ByteIOContext *pb = &s->pb;
263 FFMContext *ffm = s->priv_data;
264 int i;
265
266 /* flush packets */
267 if (ffm->packet_ptr > ffm->packet)
268 flush_packet(s);
269
270 put_flush_packet(pb);
271
272 if (!url_is_streamed(pb)) {
273 int64_t size;
274 /* update the write offset */
275 size = url_ftell(pb);
276 url_fseek(pb, 8, SEEK_SET);
277 put_be64(pb, size);
278 put_flush_packet(pb);
279 }
280
281 return 0;
282 }
283 #endif //CONFIG_ENCODERS
284
285 /* ffm demux */
286
287 static int ffm_is_avail_data(AVFormatContext *s, int size)
288 {
289 FFMContext *ffm = s->priv_data;
290 offset_t pos, avail_size;
291 int len;
292
293 len = ffm->packet_end - ffm->packet_ptr;
294 if (!ffm_nopts) {
295 /* XXX: I don't understand this test, so I disabled it for testing */
296 if (size <= len)
297 return 1;
298 }
299 pos = url_ftell(&s->pb);
300 if (pos == ffm->write_index) {
301 /* exactly at the end of stream */
302 return 0;
303 } else if (pos < ffm->write_index) {
304 avail_size = ffm->write_index - pos;
305 } else {
306 avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE);
307 }
308 avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len;
309 if (size <= avail_size)
310 return 1;
311 else
312 return 0;
313 }
314
315 /* first is true if we read the frame header */
316 static int ffm_read_data(AVFormatContext *s,
317 uint8_t *buf, int size, int first)
318 {
319 FFMContext *ffm = s->priv_data;
320 ByteIOContext *pb = &s->pb;
321 int len, fill_size, size1, frame_offset;
322
323 size1 = size;
324 while (size > 0) {
325 redo:
326 len = ffm->packet_end - ffm->packet_ptr;
327 if (len > size)
328 len = size;
329 if (len == 0) {
330 if (url_ftell(pb) == ffm->file_size)
331 url_fseek(pb, ffm->packet_size, SEEK_SET);
332 retry_read:
333 get_be16(pb); /* PACKET_ID */
334 fill_size = get_be16(pb);
335 ffm->pts = get_be64(pb);
336 frame_offset = get_be16(pb);
337 get_buffer(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE);
338 ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size);
339 if (ffm->packet_end < ffm->packet)
340 return -1;
341 /* if first packet or resynchronization packet, we must
342 handle it specifically */
343 if (ffm->first_packet || (frame_offset & 0x8000)) {
344 if (!frame_offset) {
345 /* This packet has no frame headers in it */
346 if (url_ftell(pb) >= ffm->packet_size * 3) {
347 url_fseek(pb, -ffm->packet_size * 2, SEEK_CUR);
348 goto retry_read;
349 }
350 /* This is bad, we cannot find a valid frame header */
351 return 0;
352 }
353 ffm->first_packet = 0;
354 if ((frame_offset & 0x7ffff) < FFM_HEADER_SIZE)
355 return -1;
356 ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE;
357 if (!first)
358 break;
359 } else {
360 ffm->packet_ptr = ffm->packet;
361 }
362 goto redo;
363 }
364 memcpy(buf, ffm->packet_ptr, len);
365 buf += len;
366 ffm->packet_ptr += len;
367 size -= len;
368 first = 0;
369 }
370 return size1 - size;
371 }
372
373
374 static void adjust_write_index(AVFormatContext *s)
375 {
376 FFMContext *ffm = s->priv_data;
377 ByteIOContext *pb = &s->pb;
378 int64_t pts;
379 //offset_t orig_write_index = ffm->write_index;
380 offset_t pos_min, pos_max;
381 int64_t pts_start;
382 offset_t ptr = url_ftell(pb);
383
384
385 pos_min = 0;
386 pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
387
388 pts_start = get_pts(s, pos_min);
389
390 pts = get_pts(s, pos_max);
391
392 if (pts - 100000 > pts_start)
393 goto end;
394
395 ffm->write_index = FFM_PACKET_SIZE;
396
397 pts_start = get_pts(s, pos_min);
398
399 pts = get_pts(s, pos_max);
400
401 if (pts - 100000 <= pts_start) {
402 while (1) {
403 offset_t newpos;
404 int64_t newpts;
405
406 newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE;
407
408 if (newpos == pos_min)
409 break;
410
411 newpts = get_pts(s, newpos);
412
413 if (newpts - 100000 <= pts) {
414 pos_max = newpos;
415 pts = newpts;
416 } else {
417 pos_min = newpos;
418 }
419 }
420 ffm->write_index += pos_max;
421 }
422
423 //printf("Adjusted write index from %lld to %lld: pts=%0.6f\n", orig_write_index, ffm->write_index, pts / 1000000.);
424 //printf("pts range %0.6f - %0.6f\n", get_pts(s, 0) / 1000000. , get_pts(s, ffm->file_size - 2 * FFM_PACKET_SIZE) / 1000000. );
425
426 end:
427 url_fseek(pb, ptr, SEEK_SET);
428 }
429
430
431 static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap)
432 {
433 FFMContext *ffm = s->priv_data;
434 AVStream *st;
435 FFMStream *fst;
436 ByteIOContext *pb = &s->pb;
437 AVCodecContext *codec;
438 int i, nb_streams;
439 uint32_t tag;
440
441 /* header */
442 tag = get_le32(pb);
443 if (tag != MKTAG('F', 'F', 'M', '1'))
444 goto fail;
445 ffm->packet_size = get_be32(pb);
446 if (ffm->packet_size != FFM_PACKET_SIZE)
447 goto fail;
448 ffm->write_index = get_be64(pb);
449 /* get also filesize */
450 if (!url_is_streamed(pb)) {
451 ffm->file_size = url_filesize(url_fileno(pb));
452 adjust_write_index(s);
453 } else {
454 ffm->file_size = (uint64_t_C(1) << 63) - 1;
455 }
456
457 nb_streams = get_be32(pb);
458 get_be32(pb); /* total bitrate */
459 /* read each stream */
460 for(i=0;i<nb_streams;i++) {
461 char rc_eq_buf[128];
462
463 st = av_new_stream(s, 0);
464 if (!st)
465 goto fail;
466 fst = av_mallocz(sizeof(FFMStream));
467 if (!fst)
468 goto fail;
469
470 av_set_pts_info(st, 64, 1, 1000000);
471
472 st->priv_data = fst;
473
474 codec = &st->codec;
475 /* generic info */
476 st->codec.codec_id = get_be32(pb);
477 st->codec.codec_type = get_byte(pb); /* codec_type */
478 codec->bit_rate = get_be32(pb);
479 st->quality = get_be32(pb);
480 codec->flags = get_be32(pb);
481 /* specific info */
482 switch(codec->codec_type) {
483 case CODEC_TYPE_VIDEO:
484 codec->frame_rate_base = get_be32(pb);
485 codec->frame_rate = get_be32(pb);
486 codec->width = get_be16(pb);
487 codec->height = get_be16(pb);
488 codec->gop_size = get_be16(pb);
489 codec->qmin = get_byte(pb);
490 codec->qmax = get_byte(pb);
491 codec->max_qdiff = get_byte(pb);
492 codec->qcompress = get_be16(pb) / 10000.0;
493 codec->qblur = get_be16(pb) / 10000.0;
494 codec->bit_rate_tolerance = get_be32(pb);
495 codec->rc_eq = av_strdup(get_strz(pb, rc_eq_buf, sizeof(rc_eq_buf)));
496 codec->rc_max_rate = get_be32(pb);
497 codec->rc_min_rate = get_be32(pb);
498 codec->rc_buffer_size = get_be32(pb);
499 codec->i_quant_factor = get_be64_double(pb);
500 codec->b_quant_factor = get_be64_double(pb);
501 codec->i_quant_offset = get_be64_double(pb);
502 codec->b_quant_offset = get_be64_double(pb);
503 codec->dct_algo = get_be32(pb);
504 break;
505 case CODEC_TYPE_AUDIO:
506 codec->sample_rate = get_be32(pb);
507 codec->channels = get_le16(pb);
508 codec->frame_size = get_le16(pb);
509 break;
510 default:
511 goto fail;
512 }
513
514 }
515
516 /* get until end of block reached */
517 while ((url_ftell(pb) % ffm->packet_size) != 0)
518 get_byte(pb);
519
520 /* init packet demux */
521 ffm->packet_ptr = ffm->packet;
522 ffm->packet_end = ffm->packet;
523 ffm->frame_offset = 0;
524 ffm->pts = 0;
525 ffm->read_state = READ_HEADER;
526 ffm->first_packet = 1;
527 return 0;
528 fail:
529 for(i=0;i<s->nb_streams;i++) {
530 st = s->streams[i];
531 if (st) {
532 av_freep(&st->priv_data);
533 av_free(st);
534 }
535 }
536 return -1;
537 }
538
539 /* return < 0 if eof */
540 static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)
541 {
542 int size;
543 FFMContext *ffm = s->priv_data;
544 int duration;
545
546 switch(ffm->read_state) {
547 case READ_HEADER:
548 if (!ffm_is_avail_data(s, FRAME_HEADER_SIZE)) {
549 return -EAGAIN;
550 }
551 #if 0
552 printf("pos=%08Lx spos=%Lx, write_index=%Lx size=%Lx\n",
553 url_ftell(&s->pb), s->pb.pos, ffm->write_index, ffm->file_size);
554 #endif
555 if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) !=
556 FRAME_HEADER_SIZE)
557 return -EAGAIN;
558 #if 0
559 {
560 int i;
561 for(i=0;i<FRAME_HEADER_SIZE;i++)
562 printf("%02x ", ffm->header[i]);
563 printf("\n");
564 }
565 #endif
566 ffm->read_state = READ_DATA;
567 /* fall thru */
568 case READ_DATA:
569 size = (ffm->header[2] << 16) | (ffm->header[3] << 8) | ffm->header[4];
570 if (!ffm_is_avail_data(s, size)) {
571 return -EAGAIN;
572 }
573
574 duration = (ffm->header[5] << 16) | (ffm->header[6] << 8) | ffm->header[7];
575
576 av_new_packet(pkt, size);
577 pkt->stream_index = ffm->header[0];
578 if (ffm->header[1] & FLAG_KEY_FRAME)
579 pkt->flags |= PKT_FLAG_KEY;
580
581 ffm->read_state = READ_HEADER;
582 if (ffm_read_data(s, pkt->data, size, 0) != size) {
583 /* bad case: desynchronized packet. we cancel all the packet loading */
584 av_free_packet(pkt);
585 return -EAGAIN;
586 }
587 pkt->pts = ffm->pts;
588 pkt->duration = duration;
589 break;
590 }
591 return 0;
592 }
593
594 //#define DEBUG_SEEK
595
596 /* pos is between 0 and file_size - FFM_PACKET_SIZE. It is translated
597 by the write position inside this function */
598 static void ffm_seek1(AVFormatContext *s, offset_t pos1)
599 {
600 FFMContext *ffm = s->priv_data;
601 ByteIOContext *pb = &s->pb;
602 offset_t pos;
603
604 pos = pos1 + ffm->write_index;
605 if (pos >= ffm->file_size)
606 pos -= (ffm->file_size - FFM_PACKET_SIZE);
607 #ifdef DEBUG_SEEK
608 printf("seek to %Lx -> %Lx\n", pos1, pos);
609 #endif
610 url_fseek(pb, pos, SEEK_SET);
611 }
612
613 static int64_t get_pts(AVFormatContext *s, offset_t pos)
614 {
615 ByteIOContext *pb = &s->pb;
616 int64_t pts;
617
618 ffm_seek1(s, pos);
619 url_fskip(pb, 4);
620 pts = get_be64(pb);
621 #ifdef DEBUG_SEEK
622 printf("pts=%0.6f\n", pts / 1000000.0);
623 #endif
624 return pts;
625 }
626
627 /* seek to a given time in the file. The file read pointer is
628 positionned at or before pts. XXX: the following code is quite
629 approximative */
630 static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags)
631 {
632 FFMContext *ffm = s->priv_data;
633 offset_t pos_min, pos_max, pos;
634 int64_t pts_min, pts_max, pts;
635 double pos1;
636
637 #ifdef DEBUG_SEEK
638 printf("wanted_pts=%0.6f\n", wanted_pts / 1000000.0);
639 #endif
640 /* find the position using linear interpolation (better than
641 dichotomy in typical cases) */
642 pos_min = 0;
643 pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
644 while (pos_min <= pos_max) {
645 pts_min = get_pts(s, pos_min);
646 pts_max = get_pts(s, pos_max);
647 /* linear interpolation */
648 pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) /
649 (double)(pts_max - pts_min);
650 pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE;
651 if (pos <= pos_min)
652 pos = pos_min;
653 else if (pos >= pos_max)
654 pos = pos_max;
655 pts = get_pts(s, pos);
656 /* check if we are lucky */
657 if (pts == wanted_pts) {
658 goto found;
659 } else if (pts > wanted_pts) {
660 pos_max = pos - FFM_PACKET_SIZE;
661 } else {
662 pos_min = pos + FFM_PACKET_SIZE;
663 }
664 }
665 pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max;
666 if (pos > 0)
667 pos -= FFM_PACKET_SIZE;
668 found:
669 ffm_seek1(s, pos);
670 return 0;
671 }
672
673 offset_t ffm_read_write_index(int fd)
674 {
675 uint8_t buf[8];
676 offset_t pos;
677 int i;
678
679 lseek(fd, 8, SEEK_SET);
680 read(fd, buf, 8);
681 pos = 0;
682 for(i=0;i<8;i++)
683 pos |= (int64_t)buf[i] << (56 - i * 8);
684 return pos;
685 }
686
687 void ffm_write_write_index(int fd, offset_t pos)
688 {
689 uint8_t buf[8];
690 int i;
691
692 for(i=0;i<8;i++)
693 buf[i] = (pos >> (56 - i * 8)) & 0xff;
694 lseek(fd, 8, SEEK_SET);
695 write(fd, buf, 8);
696 }
697
698 void ffm_set_write_index(AVFormatContext *s, offset_t pos, offset_t file_size)
699 {
700 FFMContext *ffm = s->priv_data;
701 ffm->write_index = pos;
702 ffm->file_size = file_size;
703 }
704
705 static int ffm_read_close(AVFormatContext *s)
706 {
707 AVStream *st;
708 int i;
709
710 for(i=0;i<s->nb_streams;i++) {
711 st = s->streams[i];
712 av_freep(&st->priv_data);
713 }
714 return 0;
715 }
716
717 static int ffm_probe(AVProbeData *p)
718 {
719 if (p->buf_size >= 4 &&
720 p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' &&
721 p->buf[3] == '1')
722 return AVPROBE_SCORE_MAX + 1;
723 return 0;
724 }
725
726 static AVInputFormat ffm_iformat = {
727 "ffm",
728 "ffm format",
729 sizeof(FFMContext),
730 ffm_probe,
731 ffm_read_header,
732 ffm_read_packet,
733 ffm_read_close,
734 ffm_seek,
735 };
736
737 #ifdef CONFIG_ENCODERS
738 static AVOutputFormat ffm_oformat = {
739 "ffm",
740 "ffm format",
741 "",
742 "ffm",
743 sizeof(FFMContext),
744 /* not really used */
745 CODEC_ID_MP2,
746 CODEC_ID_MPEG1VIDEO,
747 ffm_write_header,
748 ffm_write_packet,
749 ffm_write_trailer,
750 };
751 #endif //CONFIG_ENCODERS
752
753 int ffm_init(void)
754 {
755 av_register_input_format(&ffm_iformat);
756 #ifdef CONFIG_ENCODERS
757 av_register_output_format(&ffm_oformat);
758 #endif //CONFIG_ENCODERS
759 return 0;
760 }