This fixes error handling for BeOS, removing the need for some ifdefs.
[libav.git] / libavformat / ffm.c
1 /*
2 * FFM (ffserver live feed) muxer and demuxer
3 * Copyright (c) 2001 Fabrice Bellard.
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21 #include "avformat.h"
22 #include <unistd.h>
23
24 /* The FFM file is made of blocks of fixed size */
25 #define FFM_HEADER_SIZE 14
26 #define PACKET_ID 0x666d
27
28 /* each packet contains frames (which can span several packets */
29 #define FRAME_HEADER_SIZE 8
30 #define FLAG_KEY_FRAME 0x01
31
32 typedef struct FFMStream {
33 int64_t pts;
34 } FFMStream;
35
36 enum {
37 READ_HEADER,
38 READ_DATA,
39 };
40
41 typedef struct FFMContext {
42 /* only reading mode */
43 offset_t write_index, file_size;
44 int read_state;
45 uint8_t header[FRAME_HEADER_SIZE];
46
47 /* read and write */
48 int first_packet; /* true if first packet, needed to set the discontinuity tag */
49 int first_frame_in_packet; /* true if first frame in packet, needed to know if PTS information is valid */
50 int packet_size;
51 int frame_offset;
52 int64_t pts;
53 uint8_t *packet_ptr, *packet_end;
54 uint8_t packet[FFM_PACKET_SIZE];
55 } FFMContext;
56
57 static int64_t get_pts(AVFormatContext *s, offset_t pos);
58
59 /* disable pts hack for testing */
60 int ffm_nopts = 0;
61
62 #ifdef CONFIG_MUXERS
63 static void flush_packet(AVFormatContext *s)
64 {
65 FFMContext *ffm = s->priv_data;
66 int fill_size, h;
67 ByteIOContext *pb = &s->pb;
68
69 fill_size = ffm->packet_end - ffm->packet_ptr;
70 memset(ffm->packet_ptr, 0, fill_size);
71
72 if (url_ftell(pb) % ffm->packet_size)
73 av_abort();
74
75 /* put header */
76 put_be16(pb, PACKET_ID);
77 put_be16(pb, fill_size);
78 put_be64(pb, ffm->pts);
79 h = ffm->frame_offset;
80 if (ffm->first_packet)
81 h |= 0x8000;
82 put_be16(pb, h);
83 put_buffer(pb, ffm->packet, ffm->packet_end - ffm->packet);
84 put_flush_packet(pb);
85
86 /* prepare next packet */
87 ffm->frame_offset = 0; /* no key frame */
88 ffm->pts = 0; /* no pts */
89 ffm->packet_ptr = ffm->packet;
90 ffm->first_packet = 0;
91 }
92
93 /* 'first' is true if first data of a frame */
94 static void ffm_write_data(AVFormatContext *s,
95 const uint8_t *buf, int size,
96 int64_t pts, int first)
97 {
98 FFMContext *ffm = s->priv_data;
99 int len;
100
101 if (first && ffm->frame_offset == 0)
102 ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
103 if (first && ffm->pts == 0)
104 ffm->pts = pts;
105
106 /* write as many packets as needed */
107 while (size > 0) {
108 len = ffm->packet_end - ffm->packet_ptr;
109 if (len > size)
110 len = size;
111 memcpy(ffm->packet_ptr, buf, len);
112
113 ffm->packet_ptr += len;
114 buf += len;
115 size -= len;
116 if (ffm->packet_ptr >= ffm->packet_end) {
117 /* special case : no pts in packet : we leave the current one */
118 if (ffm->pts == 0)
119 ffm->pts = pts;
120
121 flush_packet(s);
122 }
123 }
124 }
125
126 static int ffm_write_header(AVFormatContext *s)
127 {
128 FFMContext *ffm = s->priv_data;
129 AVStream *st;
130 FFMStream *fst;
131 ByteIOContext *pb = &s->pb;
132 AVCodecContext *codec;
133 int bit_rate, i;
134
135 ffm->packet_size = FFM_PACKET_SIZE;
136
137 /* header */
138 put_le32(pb, MKTAG('F', 'F', 'M', '1'));
139 put_be32(pb, ffm->packet_size);
140 /* XXX: store write position in other file ? */
141 put_be64(pb, ffm->packet_size); /* current write position */
142
143 put_be32(pb, s->nb_streams);
144 bit_rate = 0;
145 for(i=0;i<s->nb_streams;i++) {
146 st = s->streams[i];
147 bit_rate += st->codec->bit_rate;
148 }
149 put_be32(pb, bit_rate);
150
151 /* list of streams */
152 for(i=0;i<s->nb_streams;i++) {
153 st = s->streams[i];
154 fst = av_mallocz(sizeof(FFMStream));
155 if (!fst)
156 goto fail;
157 av_set_pts_info(st, 64, 1, 1000000);
158 st->priv_data = fst;
159
160 codec = st->codec;
161 /* generic info */
162 put_be32(pb, codec->codec_id);
163 put_byte(pb, codec->codec_type);
164 put_be32(pb, codec->bit_rate);
165 put_be32(pb, st->quality);
166 put_be32(pb, codec->flags);
167 put_be32(pb, codec->flags2);
168 put_be32(pb, codec->debug);
169 /* specific info */
170 switch(codec->codec_type) {
171 case CODEC_TYPE_VIDEO:
172 put_be32(pb, codec->time_base.num);
173 put_be32(pb, codec->time_base.den);
174 put_be16(pb, codec->width);
175 put_be16(pb, codec->height);
176 put_be16(pb, codec->gop_size);
177 put_be32(pb, codec->pix_fmt);
178 put_byte(pb, codec->qmin);
179 put_byte(pb, codec->qmax);
180 put_byte(pb, codec->max_qdiff);
181 put_be16(pb, (int) (codec->qcompress * 10000.0));
182 put_be16(pb, (int) (codec->qblur * 10000.0));
183 put_be32(pb, codec->bit_rate_tolerance);
184 put_strz(pb, codec->rc_eq);
185 put_be32(pb, codec->rc_max_rate);
186 put_be32(pb, codec->rc_min_rate);
187 put_be32(pb, codec->rc_buffer_size);
188 put_be64(pb, av_dbl2int(codec->i_quant_factor));
189 put_be64(pb, av_dbl2int(codec->b_quant_factor));
190 put_be64(pb, av_dbl2int(codec->i_quant_offset));
191 put_be64(pb, av_dbl2int(codec->b_quant_offset));
192 put_be32(pb, codec->dct_algo);
193 put_be32(pb, codec->strict_std_compliance);
194 put_be32(pb, codec->max_b_frames);
195 put_be32(pb, codec->luma_elim_threshold);
196 put_be32(pb, codec->chroma_elim_threshold);
197 put_be32(pb, codec->mpeg_quant);
198 put_be32(pb, codec->intra_dc_precision);
199 put_be32(pb, codec->me_method);
200 put_be32(pb, codec->mb_decision);
201 put_be32(pb, codec->nsse_weight);
202 put_be32(pb, codec->frame_skip_cmp);
203 put_be64(pb, av_dbl2int(codec->rc_buffer_aggressivity));
204 break;
205 case CODEC_TYPE_AUDIO:
206 put_be32(pb, codec->sample_rate);
207 put_le16(pb, codec->channels);
208 put_le16(pb, codec->frame_size);
209 break;
210 default:
211 return -1;
212 }
213 /* hack to have real time */
214 if (ffm_nopts)
215 fst->pts = 0;
216 else
217 fst->pts = av_gettime();
218 }
219
220 /* flush until end of block reached */
221 while ((url_ftell(pb) % ffm->packet_size) != 0)
222 put_byte(pb, 0);
223
224 put_flush_packet(pb);
225
226 /* init packet mux */
227 ffm->packet_ptr = ffm->packet;
228 ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
229 assert(ffm->packet_end >= ffm->packet);
230 ffm->frame_offset = 0;
231 ffm->pts = 0;
232 ffm->first_packet = 1;
233
234 return 0;
235 fail:
236 for(i=0;i<s->nb_streams;i++) {
237 st = s->streams[i];
238 av_freep(&st->priv_data);
239 }
240 return -1;
241 }
242
243 static int ffm_write_packet(AVFormatContext *s, AVPacket *pkt)
244 {
245 AVStream *st = s->streams[pkt->stream_index];
246 FFMStream *fst = st->priv_data;
247 int64_t pts;
248 uint8_t header[FRAME_HEADER_SIZE];
249 int duration;
250 int size= pkt->size;
251
252 //XXX/FIXME use duration from pkt
253 if (st->codec->codec_type == CODEC_TYPE_AUDIO) {
254 duration = ((float)st->codec->frame_size / st->codec->sample_rate * 1000000.0);
255 } else {
256 duration = (1000000.0 * st->codec->time_base.num / (float)st->codec->time_base.den);
257 }
258
259 pts = fst->pts;
260 /* packet size & key_frame */
261 header[0] = pkt->stream_index;
262 header[1] = 0;
263 if (pkt->flags & PKT_FLAG_KEY)
264 header[1] |= FLAG_KEY_FRAME;
265 header[2] = (size >> 16) & 0xff;
266 header[3] = (size >> 8) & 0xff;
267 header[4] = size & 0xff;
268 header[5] = (duration >> 16) & 0xff;
269 header[6] = (duration >> 8) & 0xff;
270 header[7] = duration & 0xff;
271 ffm_write_data(s, header, FRAME_HEADER_SIZE, pts, 1);
272 ffm_write_data(s, pkt->data, size, pts, 0);
273
274 fst->pts += duration;
275 return 0;
276 }
277
278 static int ffm_write_trailer(AVFormatContext *s)
279 {
280 ByteIOContext *pb = &s->pb;
281 FFMContext *ffm = s->priv_data;
282
283 /* flush packets */
284 if (ffm->packet_ptr > ffm->packet)
285 flush_packet(s);
286
287 put_flush_packet(pb);
288
289 if (!url_is_streamed(pb)) {
290 int64_t size;
291 /* update the write offset */
292 size = url_ftell(pb);
293 url_fseek(pb, 8, SEEK_SET);
294 put_be64(pb, size);
295 put_flush_packet(pb);
296 }
297
298 return 0;
299 }
300 #endif //CONFIG_MUXERS
301
302 /* ffm demux */
303
304 static int ffm_is_avail_data(AVFormatContext *s, int size)
305 {
306 FFMContext *ffm = s->priv_data;
307 offset_t pos, avail_size;
308 int len;
309
310 len = ffm->packet_end - ffm->packet_ptr;
311 if (!ffm_nopts) {
312 /* XXX: I don't understand this test, so I disabled it for testing */
313 if (size <= len)
314 return 1;
315 }
316 pos = url_ftell(&s->pb);
317 if (pos == ffm->write_index) {
318 /* exactly at the end of stream */
319 return 0;
320 } else if (pos < ffm->write_index) {
321 avail_size = ffm->write_index - pos;
322 } else {
323 avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE);
324 }
325 avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len;
326 if (size <= avail_size)
327 return 1;
328 else
329 return 0;
330 }
331
332 /* first is true if we read the frame header */
333 static int ffm_read_data(AVFormatContext *s,
334 uint8_t *buf, int size, int first)
335 {
336 FFMContext *ffm = s->priv_data;
337 ByteIOContext *pb = &s->pb;
338 int len, fill_size, size1, frame_offset;
339
340 size1 = size;
341 while (size > 0) {
342 redo:
343 len = ffm->packet_end - ffm->packet_ptr;
344 if (len > size)
345 len = size;
346 if (len == 0) {
347 if (url_ftell(pb) == ffm->file_size)
348 url_fseek(pb, ffm->packet_size, SEEK_SET);
349 retry_read:
350 get_be16(pb); /* PACKET_ID */
351 fill_size = get_be16(pb);
352 ffm->pts = get_be64(pb);
353 ffm->first_frame_in_packet = 1;
354 frame_offset = get_be16(pb);
355 get_buffer(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE);
356 ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size);
357 if (ffm->packet_end < ffm->packet)
358 return -1;
359 /* if first packet or resynchronization packet, we must
360 handle it specifically */
361 if (ffm->first_packet || (frame_offset & 0x8000)) {
362 if (!frame_offset) {
363 /* This packet has no frame headers in it */
364 if (url_ftell(pb) >= ffm->packet_size * 3) {
365 url_fseek(pb, -ffm->packet_size * 2, SEEK_CUR);
366 goto retry_read;
367 }
368 /* This is bad, we cannot find a valid frame header */
369 return 0;
370 }
371 ffm->first_packet = 0;
372 if ((frame_offset & 0x7ffff) < FFM_HEADER_SIZE)
373 return -1;
374 ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE;
375 if (!first)
376 break;
377 } else {
378 ffm->packet_ptr = ffm->packet;
379 }
380 goto redo;
381 }
382 memcpy(buf, ffm->packet_ptr, len);
383 buf += len;
384 ffm->packet_ptr += len;
385 size -= len;
386 first = 0;
387 }
388 return size1 - size;
389 }
390
391
392 static void adjust_write_index(AVFormatContext *s)
393 {
394 FFMContext *ffm = s->priv_data;
395 ByteIOContext *pb = &s->pb;
396 int64_t pts;
397 //offset_t orig_write_index = ffm->write_index;
398 offset_t pos_min, pos_max;
399 int64_t pts_start;
400 offset_t ptr = url_ftell(pb);
401
402
403 pos_min = 0;
404 pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
405
406 pts_start = get_pts(s, pos_min);
407
408 pts = get_pts(s, pos_max);
409
410 if (pts - 100000 > pts_start)
411 goto end;
412
413 ffm->write_index = FFM_PACKET_SIZE;
414
415 pts_start = get_pts(s, pos_min);
416
417 pts = get_pts(s, pos_max);
418
419 if (pts - 100000 <= pts_start) {
420 while (1) {
421 offset_t newpos;
422 int64_t newpts;
423
424 newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE;
425
426 if (newpos == pos_min)
427 break;
428
429 newpts = get_pts(s, newpos);
430
431 if (newpts - 100000 <= pts) {
432 pos_max = newpos;
433 pts = newpts;
434 } else {
435 pos_min = newpos;
436 }
437 }
438 ffm->write_index += pos_max;
439 }
440
441 //printf("Adjusted write index from %"PRId64" to %"PRId64": pts=%0.6f\n", orig_write_index, ffm->write_index, pts / 1000000.);
442 //printf("pts range %0.6f - %0.6f\n", get_pts(s, 0) / 1000000. , get_pts(s, ffm->file_size - 2 * FFM_PACKET_SIZE) / 1000000. );
443
444 end:
445 url_fseek(pb, ptr, SEEK_SET);
446 }
447
448
449 static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap)
450 {
451 FFMContext *ffm = s->priv_data;
452 AVStream *st;
453 FFMStream *fst;
454 ByteIOContext *pb = &s->pb;
455 AVCodecContext *codec;
456 int i, nb_streams;
457 uint32_t tag;
458
459 /* header */
460 tag = get_le32(pb);
461 if (tag != MKTAG('F', 'F', 'M', '1'))
462 goto fail;
463 ffm->packet_size = get_be32(pb);
464 if (ffm->packet_size != FFM_PACKET_SIZE)
465 goto fail;
466 ffm->write_index = get_be64(pb);
467 /* get also filesize */
468 if (!url_is_streamed(pb)) {
469 ffm->file_size = url_fsize(pb);
470 adjust_write_index(s);
471 } else {
472 ffm->file_size = (UINT64_C(1) << 63) - 1;
473 }
474
475 nb_streams = get_be32(pb);
476 get_be32(pb); /* total bitrate */
477 /* read each stream */
478 for(i=0;i<nb_streams;i++) {
479 char rc_eq_buf[128];
480
481 st = av_new_stream(s, 0);
482 if (!st)
483 goto fail;
484 fst = av_mallocz(sizeof(FFMStream));
485 if (!fst)
486 goto fail;
487 s->streams[i] = st;
488
489 av_set_pts_info(st, 64, 1, 1000000);
490
491 st->priv_data = fst;
492
493 codec = st->codec;
494 /* generic info */
495 codec->codec_id = get_be32(pb);
496 codec->codec_type = get_byte(pb); /* codec_type */
497 codec->bit_rate = get_be32(pb);
498 st->quality = get_be32(pb);
499 codec->flags = get_be32(pb);
500 codec->flags2 = get_be32(pb);
501 codec->debug = get_be32(pb);
502 /* specific info */
503 switch(codec->codec_type) {
504 case CODEC_TYPE_VIDEO:
505 codec->time_base.num = get_be32(pb);
506 codec->time_base.den = get_be32(pb);
507 codec->width = get_be16(pb);
508 codec->height = get_be16(pb);
509 codec->gop_size = get_be16(pb);
510 codec->pix_fmt = get_be32(pb);
511 codec->qmin = get_byte(pb);
512 codec->qmax = get_byte(pb);
513 codec->max_qdiff = get_byte(pb);
514 codec->qcompress = get_be16(pb) / 10000.0;
515 codec->qblur = get_be16(pb) / 10000.0;
516 codec->bit_rate_tolerance = get_be32(pb);
517 codec->rc_eq = av_strdup(get_strz(pb, rc_eq_buf, sizeof(rc_eq_buf)));
518 codec->rc_max_rate = get_be32(pb);
519 codec->rc_min_rate = get_be32(pb);
520 codec->rc_buffer_size = get_be32(pb);
521 codec->i_quant_factor = av_int2dbl(get_be64(pb));
522 codec->b_quant_factor = av_int2dbl(get_be64(pb));
523 codec->i_quant_offset = av_int2dbl(get_be64(pb));
524 codec->b_quant_offset = av_int2dbl(get_be64(pb));
525 codec->dct_algo = get_be32(pb);
526 codec->strict_std_compliance = get_be32(pb);
527 codec->max_b_frames = get_be32(pb);
528 codec->luma_elim_threshold = get_be32(pb);
529 codec->chroma_elim_threshold = get_be32(pb);
530 codec->mpeg_quant = get_be32(pb);
531 codec->intra_dc_precision = get_be32(pb);
532 codec->me_method = get_be32(pb);
533 codec->mb_decision = get_be32(pb);
534 codec->nsse_weight = get_be32(pb);
535 codec->frame_skip_cmp = get_be32(pb);
536 codec->rc_buffer_aggressivity = av_int2dbl(get_be64(pb));
537 break;
538 case CODEC_TYPE_AUDIO:
539 codec->sample_rate = get_be32(pb);
540 codec->channels = get_le16(pb);
541 codec->frame_size = get_le16(pb);
542 break;
543 default:
544 goto fail;
545 }
546
547 }
548
549 /* get until end of block reached */
550 while ((url_ftell(pb) % ffm->packet_size) != 0)
551 get_byte(pb);
552
553 /* init packet demux */
554 ffm->packet_ptr = ffm->packet;
555 ffm->packet_end = ffm->packet;
556 ffm->frame_offset = 0;
557 ffm->pts = 0;
558 ffm->read_state = READ_HEADER;
559 ffm->first_packet = 1;
560 return 0;
561 fail:
562 for(i=0;i<s->nb_streams;i++) {
563 st = s->streams[i];
564 if (st) {
565 av_freep(&st->priv_data);
566 av_free(st);
567 }
568 }
569 return -1;
570 }
571
572 /* return < 0 if eof */
573 static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)
574 {
575 int size;
576 FFMContext *ffm = s->priv_data;
577 int duration;
578
579 switch(ffm->read_state) {
580 case READ_HEADER:
581 if (!ffm_is_avail_data(s, FRAME_HEADER_SIZE)) {
582 return AVERROR(EAGAIN);
583 }
584 #if 0
585 printf("pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n",
586 url_ftell(&s->pb), s->pb.pos, ffm->write_index, ffm->file_size);
587 #endif
588 if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) !=
589 FRAME_HEADER_SIZE)
590 return AVERROR(EAGAIN);
591 #if 0
592 {
593 int i;
594 for(i=0;i<FRAME_HEADER_SIZE;i++)
595 printf("%02x ", ffm->header[i]);
596 printf("\n");
597 }
598 #endif
599 ffm->read_state = READ_DATA;
600 /* fall thru */
601 case READ_DATA:
602 size = (ffm->header[2] << 16) | (ffm->header[3] << 8) | ffm->header[4];
603 if (!ffm_is_avail_data(s, size)) {
604 return AVERROR(EAGAIN);
605 }
606
607 duration = (ffm->header[5] << 16) | (ffm->header[6] << 8) | ffm->header[7];
608
609 av_new_packet(pkt, size);
610 pkt->stream_index = ffm->header[0];
611 pkt->pos = url_ftell(&s->pb);
612 if (ffm->header[1] & FLAG_KEY_FRAME)
613 pkt->flags |= PKT_FLAG_KEY;
614
615 ffm->read_state = READ_HEADER;
616 if (ffm_read_data(s, pkt->data, size, 0) != size) {
617 /* bad case: desynchronized packet. we cancel all the packet loading */
618 av_free_packet(pkt);
619 return AVERROR(EAGAIN);
620 }
621 if (ffm->first_frame_in_packet)
622 {
623 pkt->pts = ffm->pts;
624 ffm->first_frame_in_packet = 0;
625 }
626 pkt->duration = duration;
627 break;
628 }
629 return 0;
630 }
631
632 //#define DEBUG_SEEK
633
634 /* pos is between 0 and file_size - FFM_PACKET_SIZE. It is translated
635 by the write position inside this function */
636 static void ffm_seek1(AVFormatContext *s, offset_t pos1)
637 {
638 FFMContext *ffm = s->priv_data;
639 ByteIOContext *pb = &s->pb;
640 offset_t pos;
641
642 pos = pos1 + ffm->write_index;
643 if (pos >= ffm->file_size)
644 pos -= (ffm->file_size - FFM_PACKET_SIZE);
645 #ifdef DEBUG_SEEK
646 printf("seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos);
647 #endif
648 url_fseek(pb, pos, SEEK_SET);
649 }
650
651 static int64_t get_pts(AVFormatContext *s, offset_t pos)
652 {
653 ByteIOContext *pb = &s->pb;
654 int64_t pts;
655
656 ffm_seek1(s, pos);
657 url_fskip(pb, 4);
658 pts = get_be64(pb);
659 #ifdef DEBUG_SEEK
660 printf("pts=%0.6f\n", pts / 1000000.0);
661 #endif
662 return pts;
663 }
664
665 /* seek to a given time in the file. The file read pointer is
666 positionned at or before pts. XXX: the following code is quite
667 approximative */
668 static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags)
669 {
670 FFMContext *ffm = s->priv_data;
671 offset_t pos_min, pos_max, pos;
672 int64_t pts_min, pts_max, pts;
673 double pos1;
674
675 #ifdef DEBUG_SEEK
676 printf("wanted_pts=%0.6f\n", wanted_pts / 1000000.0);
677 #endif
678 /* find the position using linear interpolation (better than
679 dichotomy in typical cases) */
680 pos_min = 0;
681 pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
682 while (pos_min <= pos_max) {
683 pts_min = get_pts(s, pos_min);
684 pts_max = get_pts(s, pos_max);
685 /* linear interpolation */
686 pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) /
687 (double)(pts_max - pts_min);
688 pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE;
689 if (pos <= pos_min)
690 pos = pos_min;
691 else if (pos >= pos_max)
692 pos = pos_max;
693 pts = get_pts(s, pos);
694 /* check if we are lucky */
695 if (pts == wanted_pts) {
696 goto found;
697 } else if (pts > wanted_pts) {
698 pos_max = pos - FFM_PACKET_SIZE;
699 } else {
700 pos_min = pos + FFM_PACKET_SIZE;
701 }
702 }
703 pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max;
704 if (pos > 0)
705 pos -= FFM_PACKET_SIZE;
706 found:
707 ffm_seek1(s, pos);
708 return 0;
709 }
710
711 #ifdef CONFIG_FFSERVER
712 offset_t ffm_read_write_index(int fd)
713 {
714 uint8_t buf[8];
715 offset_t pos;
716 int i;
717
718 lseek(fd, 8, SEEK_SET);
719 read(fd, buf, 8);
720 pos = 0;
721 for(i=0;i<8;i++)
722 pos |= (int64_t)buf[i] << (56 - i * 8);
723 return pos;
724 }
725
726 void ffm_write_write_index(int fd, offset_t pos)
727 {
728 uint8_t buf[8];
729 int i;
730
731 for(i=0;i<8;i++)
732 buf[i] = (pos >> (56 - i * 8)) & 0xff;
733 lseek(fd, 8, SEEK_SET);
734 write(fd, buf, 8);
735 }
736
737 void ffm_set_write_index(AVFormatContext *s, offset_t pos, offset_t file_size)
738 {
739 FFMContext *ffm = s->priv_data;
740 ffm->write_index = pos;
741 ffm->file_size = file_size;
742 }
743 #endif // CONFIG_FFSERVER
744
745 static int ffm_read_close(AVFormatContext *s)
746 {
747 AVStream *st;
748 int i;
749
750 for(i=0;i<s->nb_streams;i++) {
751 st = s->streams[i];
752 av_freep(&st->priv_data);
753 }
754 return 0;
755 }
756
757 static int ffm_probe(AVProbeData *p)
758 {
759 if (p->buf_size >= 4 &&
760 p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' &&
761 p->buf[3] == '1')
762 return AVPROBE_SCORE_MAX + 1;
763 return 0;
764 }
765
766 #ifdef CONFIG_FFM_DEMUXER
767 AVInputFormat ffm_demuxer = {
768 "ffm",
769 "ffm format",
770 sizeof(FFMContext),
771 ffm_probe,
772 ffm_read_header,
773 ffm_read_packet,
774 ffm_read_close,
775 ffm_seek,
776 };
777 #endif
778 #ifdef CONFIG_FFM_MUXER
779 AVOutputFormat ffm_muxer = {
780 "ffm",
781 "ffm format",
782 "",
783 "ffm",
784 sizeof(FFMContext),
785 /* not really used */
786 CODEC_ID_MP2,
787 CODEC_ID_MPEG1VIDEO,
788 ffm_write_header,
789 ffm_write_packet,
790 ffm_write_trailer,
791 };
792 #endif //CONFIG_FFM_MUXER