2 * FFM (ffserver live feed) demuxer
3 * Copyright (c) 2001 Fabrice Bellard.
5 * This file is part of FFmpeg.
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.
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.
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
24 #ifdef CONFIG_FFSERVER
27 offset_t ffm_read_write_index(int fd)
31 lseek(fd, 8, SEEK_SET);
36 void ffm_write_write_index(int fd, offset_t pos)
42 buf[i] = (pos >> (56 - i * 8)) & 0xff;
43 lseek(fd, 8, SEEK_SET);
47 void ffm_set_write_index(AVFormatContext *s, offset_t pos, offset_t file_size)
49 FFMContext *ffm = s->priv_data;
50 ffm->write_index = pos;
51 ffm->file_size = file_size;
53 #endif // CONFIG_FFSERVER
55 static int ffm_is_avail_data(AVFormatContext *s, int size)
57 FFMContext *ffm = s->priv_data;
58 offset_t pos, avail_size;
61 len = ffm->packet_end - ffm->packet_ptr;
64 pos = url_ftell(s->pb);
65 if (pos == ffm->write_index) {
66 /* exactly at the end of stream */
68 } else if (pos < ffm->write_index) {
69 avail_size = ffm->write_index - pos;
71 avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE);
73 avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len;
74 if (size <= avail_size)
80 /* first is true if we read the frame header */
81 static int ffm_read_data(AVFormatContext *s,
82 uint8_t *buf, int size, int header)
84 FFMContext *ffm = s->priv_data;
85 ByteIOContext *pb = s->pb;
86 int len, fill_size, size1, frame_offset;
91 len = ffm->packet_end - ffm->packet_ptr;
97 if (url_ftell(pb) == ffm->file_size)
98 url_fseek(pb, ffm->packet_size, SEEK_SET);
100 get_be16(pb); /* PACKET_ID */
101 fill_size = get_be16(pb);
102 ffm->dts = get_be64(pb);
103 frame_offset = get_be16(pb);
104 get_buffer(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE);
105 ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size);
106 if (ffm->packet_end < ffm->packet || frame_offset < 0)
108 /* if first packet or resynchronization packet, we must
109 handle it specifically */
110 if (ffm->first_packet || (frame_offset & 0x8000)) {
112 /* This packet has no frame headers in it */
113 if (url_ftell(pb) >= ffm->packet_size * 3) {
114 url_fseek(pb, -ffm->packet_size * 2, SEEK_CUR);
117 /* This is bad, we cannot find a valid frame header */
120 ffm->first_packet = 0;
121 if ((frame_offset & 0x7fff) < FFM_HEADER_SIZE)
123 ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE;
127 ffm->packet_ptr = ffm->packet;
131 memcpy(buf, ffm->packet_ptr, len);
133 ffm->packet_ptr += len;
142 /* pos is between 0 and file_size - FFM_PACKET_SIZE. It is translated
143 by the write position inside this function */
144 static void ffm_seek1(AVFormatContext *s, offset_t pos1)
146 FFMContext *ffm = s->priv_data;
147 ByteIOContext *pb = s->pb;
150 pos = pos1 + ffm->write_index;
151 if (pos >= ffm->file_size)
152 pos -= (ffm->file_size - FFM_PACKET_SIZE);
154 av_log(s, AV_LOG_DEBUG, "seek to %"PRIx64" -> %"PRIx64"\n", pos1, pos);
156 url_fseek(pb, pos, SEEK_SET);
159 static int64_t get_dts(AVFormatContext *s, offset_t pos)
161 ByteIOContext *pb = s->pb;
168 av_log(s, AV_LOG_DEBUG, "pts=%0.6f\n", pts / 1000000.0);
173 static void adjust_write_index(AVFormatContext *s)
175 FFMContext *ffm = s->priv_data;
176 ByteIOContext *pb = s->pb;
178 //offset_t orig_write_index = ffm->write_index;
179 offset_t pos_min, pos_max;
181 offset_t ptr = url_ftell(pb);
185 pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
187 pts_start = get_dts(s, pos_min);
189 pts = get_dts(s, pos_max);
191 if (pts - 100000 > pts_start)
194 ffm->write_index = FFM_PACKET_SIZE;
196 pts_start = get_dts(s, pos_min);
198 pts = get_dts(s, pos_max);
200 if (pts - 100000 <= pts_start) {
205 newpos = ((pos_max + pos_min) / (2 * FFM_PACKET_SIZE)) * FFM_PACKET_SIZE;
207 if (newpos == pos_min)
210 newpts = get_dts(s, newpos);
212 if (newpts - 100000 <= pts) {
219 ffm->write_index += pos_max;
222 //printf("Adjusted write index from %"PRId64" to %"PRId64": pts=%0.6f\n", orig_write_index, ffm->write_index, pts / 1000000.);
223 //printf("pts range %0.6f - %0.6f\n", get_dts(s, 0) / 1000000. , get_dts(s, ffm->file_size - 2 * FFM_PACKET_SIZE) / 1000000. );
226 url_fseek(pb, ptr, SEEK_SET);
230 static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap)
232 FFMContext *ffm = s->priv_data;
234 ByteIOContext *pb = s->pb;
235 AVCodecContext *codec;
241 if (tag != MKTAG('F', 'F', 'M', '1'))
243 ffm->packet_size = get_be32(pb);
244 if (ffm->packet_size != FFM_PACKET_SIZE)
246 ffm->write_index = get_be64(pb);
247 /* get also filesize */
248 if (!url_is_streamed(pb)) {
249 ffm->file_size = url_fsize(pb);
250 adjust_write_index(s);
252 ffm->file_size = (UINT64_C(1) << 63) - 1;
255 nb_streams = get_be32(pb);
256 get_be32(pb); /* total bitrate */
257 /* read each stream */
258 for(i=0;i<nb_streams;i++) {
261 st = av_new_stream(s, 0);
266 av_set_pts_info(st, 64, 1, 1000000);
270 codec->codec_id = get_be32(pb);
271 codec->codec_type = get_byte(pb); /* codec_type */
272 codec->bit_rate = get_be32(pb);
273 st->quality = get_be32(pb);
274 codec->flags = get_be32(pb);
275 codec->flags2 = get_be32(pb);
276 codec->debug = get_be32(pb);
278 switch(codec->codec_type) {
279 case CODEC_TYPE_VIDEO:
280 codec->time_base.num = get_be32(pb);
281 codec->time_base.den = get_be32(pb);
282 codec->width = get_be16(pb);
283 codec->height = get_be16(pb);
284 codec->gop_size = get_be16(pb);
285 codec->pix_fmt = get_be32(pb);
286 codec->qmin = get_byte(pb);
287 codec->qmax = get_byte(pb);
288 codec->max_qdiff = get_byte(pb);
289 codec->qcompress = get_be16(pb) / 10000.0;
290 codec->qblur = get_be16(pb) / 10000.0;
291 codec->bit_rate_tolerance = get_be32(pb);
292 codec->rc_eq = av_strdup(get_strz(pb, rc_eq_buf, sizeof(rc_eq_buf)));
293 codec->rc_max_rate = get_be32(pb);
294 codec->rc_min_rate = get_be32(pb);
295 codec->rc_buffer_size = get_be32(pb);
296 codec->i_quant_factor = av_int2dbl(get_be64(pb));
297 codec->b_quant_factor = av_int2dbl(get_be64(pb));
298 codec->i_quant_offset = av_int2dbl(get_be64(pb));
299 codec->b_quant_offset = av_int2dbl(get_be64(pb));
300 codec->dct_algo = get_be32(pb);
301 codec->strict_std_compliance = get_be32(pb);
302 codec->max_b_frames = get_be32(pb);
303 codec->luma_elim_threshold = get_be32(pb);
304 codec->chroma_elim_threshold = get_be32(pb);
305 codec->mpeg_quant = get_be32(pb);
306 codec->intra_dc_precision = get_be32(pb);
307 codec->me_method = get_be32(pb);
308 codec->mb_decision = get_be32(pb);
309 codec->nsse_weight = get_be32(pb);
310 codec->frame_skip_cmp = get_be32(pb);
311 codec->rc_buffer_aggressivity = av_int2dbl(get_be64(pb));
312 codec->codec_tag = get_be32(pb);
313 codec->thread_count = get_byte(pb);
315 case CODEC_TYPE_AUDIO:
316 codec->sample_rate = get_be32(pb);
317 codec->channels = get_le16(pb);
318 codec->frame_size = get_le16(pb);
323 if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {
324 codec->extradata_size = get_be32(pb);
325 codec->extradata = av_malloc(codec->extradata_size);
326 if (!codec->extradata)
327 return AVERROR(ENOMEM);
328 get_buffer(pb, codec->extradata, codec->extradata_size);
332 /* get until end of block reached */
333 while ((url_ftell(pb) % ffm->packet_size) != 0)
336 /* init packet demux */
337 ffm->packet_ptr = ffm->packet;
338 ffm->packet_end = ffm->packet;
339 ffm->frame_offset = 0;
341 ffm->read_state = READ_HEADER;
342 ffm->first_packet = 1;
345 for(i=0;i<s->nb_streams;i++) {
354 /* return < 0 if eof */
355 static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)
358 FFMContext *ffm = s->priv_data;
361 switch(ffm->read_state) {
363 if (!ffm_is_avail_data(s, FRAME_HEADER_SIZE+4)) {
364 return AVERROR(EAGAIN);
366 dprintf(s, "pos=%08"PRIx64" spos=%"PRIx64", write_index=%"PRIx64" size=%"PRIx64"\n",
367 url_ftell(s->pb), s->pb->pos, ffm->write_index, ffm->file_size);
368 if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) !=
370 return AVERROR(EAGAIN);
371 if (ffm->header[1] & FLAG_DTS)
372 if (ffm_read_data(s, ffm->header+16, 4, 1) != 4)
373 return AVERROR(EAGAIN);
375 av_hexdump_log(s, AV_LOG_DEBUG, ffm->header, FRAME_HEADER_SIZE);
377 ffm->read_state = READ_DATA;
380 size = AV_RB24(ffm->header + 2);
381 if (!ffm_is_avail_data(s, size)) {
382 return AVERROR(EAGAIN);
385 duration = AV_RB24(ffm->header + 5);
387 av_new_packet(pkt, size);
388 pkt->stream_index = ffm->header[0];
389 if ((unsigned)pkt->stream_index >= s->nb_streams) {
390 av_log(s, AV_LOG_ERROR, "invalid stream index %d\n", pkt->stream_index);
392 ffm->read_state = READ_HEADER;
393 return AVERROR(EAGAIN);
395 pkt->pos = url_ftell(s->pb);
396 if (ffm->header[1] & FLAG_KEY_FRAME)
397 pkt->flags |= PKT_FLAG_KEY;
399 ffm->read_state = READ_HEADER;
400 if (ffm_read_data(s, pkt->data, size, 0) != size) {
401 /* bad case: desynchronized packet. we cancel all the packet loading */
403 return AVERROR(EAGAIN);
405 pkt->pts = AV_RB64(ffm->header+8);
406 if (ffm->header[1] & FLAG_DTS)
407 pkt->dts = pkt->pts - AV_RB32(ffm->header+16);
410 pkt->duration = duration;
416 /* seek to a given time in the file. The file read pointer is
417 positioned at or before pts. XXX: the following code is quite
419 static int ffm_seek(AVFormatContext *s, int stream_index, int64_t wanted_pts, int flags)
421 FFMContext *ffm = s->priv_data;
422 offset_t pos_min, pos_max, pos;
423 int64_t pts_min, pts_max, pts;
427 av_log(s, AV_LOG_DEBUG, "wanted_pts=%0.6f\n", wanted_pts / 1000000.0);
429 /* find the position using linear interpolation (better than
430 dichotomy in typical cases) */
432 pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
433 while (pos_min <= pos_max) {
434 pts_min = get_dts(s, pos_min);
435 pts_max = get_dts(s, pos_max);
436 /* linear interpolation */
437 pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) /
438 (double)(pts_max - pts_min);
439 pos = (((int64_t)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE;
442 else if (pos >= pos_max)
444 pts = get_dts(s, pos);
445 /* check if we are lucky */
446 if (pts == wanted_pts) {
448 } else if (pts > wanted_pts) {
449 pos_max = pos - FFM_PACKET_SIZE;
451 pos_min = pos + FFM_PACKET_SIZE;
454 pos = (flags & AVSEEK_FLAG_BACKWARD) ? pos_min : pos_max;
456 pos -= FFM_PACKET_SIZE;
460 /* reset read state */
461 ffm->read_state = READ_HEADER;
462 ffm->packet_ptr = ffm->packet;
463 ffm->packet_end = ffm->packet;
464 ffm->first_packet = 1;
469 static int ffm_probe(AVProbeData *p)
472 p->buf[0] == 'F' && p->buf[1] == 'F' && p->buf[2] == 'M' &&
474 return AVPROBE_SCORE_MAX + 1;
478 AVInputFormat ffm_demuxer = {
480 NULL_IF_CONFIG_SMALL("FFM (FFserver live feed) format"),