3 * Copyright (c) 2002 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
25 #include "libavutil/mathematics.h"
26 #include "libavutil/random_seed.h"
27 #include "libavutil/opt.h"
31 static const AVOption options
[] = {
32 FF_RTP_FLAG_OPTS(RTPMuxContext
, flags
),
33 { "payload_type", "Specify RTP payload type", offsetof(RTPMuxContext
, payload_type
), AV_OPT_TYPE_INT
, {.i64
= -1 }, -1, 127, AV_OPT_FLAG_ENCODING_PARAM
},
34 { "ssrc", "Stream identifier", offsetof(RTPMuxContext
, ssrc
), AV_OPT_TYPE_INT
, { .i64
= 0 }, INT_MIN
, INT_MAX
, AV_OPT_FLAG_ENCODING_PARAM
},
35 { "cname", "CNAME to include in RTCP SR packets", offsetof(RTPMuxContext
, cname
), AV_OPT_TYPE_STRING
, { .str
= NULL
}, 0, 0, AV_OPT_FLAG_ENCODING_PARAM
},
36 { "seq", "Starting sequence number", offsetof(RTPMuxContext
, seq
), AV_OPT_TYPE_INT
, { .i64
= -1 }, -1, 65535, AV_OPT_FLAG_ENCODING_PARAM
},
40 static const AVClass rtp_muxer_class
= {
41 .class_name
= "RTP muxer",
42 .item_name
= av_default_item_name
,
44 .version
= LIBAVUTIL_VERSION_INT
,
47 #define RTCP_SR_SIZE 28
49 static int is_supported(enum AVCodecID id
)
52 case AV_CODEC_ID_H261
:
53 case AV_CODEC_ID_H263
:
54 case AV_CODEC_ID_H263P
:
55 case AV_CODEC_ID_H264
:
56 case AV_CODEC_ID_HEVC
:
57 case AV_CODEC_ID_MPEG1VIDEO
:
58 case AV_CODEC_ID_MPEG2VIDEO
:
59 case AV_CODEC_ID_MPEG4
:
63 case AV_CODEC_ID_PCM_ALAW
:
64 case AV_CODEC_ID_PCM_MULAW
:
65 case AV_CODEC_ID_PCM_S8
:
66 case AV_CODEC_ID_PCM_S16BE
:
67 case AV_CODEC_ID_PCM_S16LE
:
68 case AV_CODEC_ID_PCM_U16BE
:
69 case AV_CODEC_ID_PCM_U16LE
:
70 case AV_CODEC_ID_PCM_U8
:
71 case AV_CODEC_ID_MPEG2TS
:
72 case AV_CODEC_ID_AMR_NB
:
73 case AV_CODEC_ID_AMR_WB
:
74 case AV_CODEC_ID_VORBIS
:
75 case AV_CODEC_ID_THEORA
:
77 case AV_CODEC_ID_ADPCM_G722
:
78 case AV_CODEC_ID_ADPCM_G726
:
79 case AV_CODEC_ID_ILBC
:
80 case AV_CODEC_ID_MJPEG
:
81 case AV_CODEC_ID_SPEEX
:
82 case AV_CODEC_ID_OPUS
:
89 static int rtp_write_header(AVFormatContext
*s1
)
91 RTPMuxContext
*s
= s1
->priv_data
;
95 if (s1
->nb_streams
!= 1) {
96 av_log(s1
, AV_LOG_ERROR
, "Only one stream supported in the RTP muxer\n");
97 return AVERROR(EINVAL
);
100 if (!is_supported(st
->codec
->codec_id
)) {
101 av_log(s1
, AV_LOG_ERROR
, "Unsupported codec %s\n", avcodec_get_name(st
->codec
->codec_id
));
106 if (s
->payload_type
< 0) {
107 /* Re-validate non-dynamic payload types */
108 if (st
->id
< RTP_PT_PRIVATE
)
109 st
->id
= ff_rtp_get_payload_type(s1
, st
->codec
, -1);
111 s
->payload_type
= st
->id
;
113 /* private option takes priority */
114 st
->id
= s
->payload_type
;
117 s
->base_timestamp
= av_get_random_seed();
118 s
->timestamp
= s
->base_timestamp
;
119 s
->cur_timestamp
= 0;
121 s
->ssrc
= av_get_random_seed();
123 s
->first_rtcp_ntp_time
= ff_ntp_time();
124 if (s1
->start_time_realtime
!= 0 && s1
->start_time_realtime
!= AV_NOPTS_VALUE
)
125 /* Round the NTP time to whole milliseconds. */
126 s
->first_rtcp_ntp_time
= (s1
->start_time_realtime
/ 1000) * 1000 +
128 // Pick a random sequence start number, but in the lower end of the
129 // available range, so that any wraparound doesn't happen immediately.
130 // (Immediate wraparound would be an issue for SRTP.)
132 if (s1
->flags
& AVFMT_FLAG_BITEXACT
) {
135 s
->seq
= av_get_random_seed() & 0x0fff;
137 s
->seq
&= 0xffff; // Use the given parameter, wrapped to the right interval
139 if (s1
->packet_size
) {
140 if (s1
->pb
->max_packet_size
)
141 s1
->packet_size
= FFMIN(s1
->packet_size
,
142 s1
->pb
->max_packet_size
);
144 s1
->packet_size
= s1
->pb
->max_packet_size
;
145 if (s1
->packet_size
<= 12) {
146 av_log(s1
, AV_LOG_ERROR
, "Max packet size %d too low\n", s1
->packet_size
);
149 s
->buf
= av_malloc(s1
->packet_size
);
151 return AVERROR(ENOMEM
);
153 s
->max_payload_size
= s1
->packet_size
- 12;
155 s
->max_frames_per_packet
= 0;
156 if (s1
->max_delay
> 0) {
157 if (st
->codec
->codec_type
== AVMEDIA_TYPE_AUDIO
) {
158 int frame_size
= av_get_audio_frame_duration(st
->codec
, 0);
160 frame_size
= st
->codec
->frame_size
;
161 if (frame_size
== 0) {
162 av_log(s1
, AV_LOG_ERROR
, "Cannot respect max delay: frame size = 0\n");
164 s
->max_frames_per_packet
=
165 av_rescale_q_rnd(s1
->max_delay
,
167 (AVRational
){ frame_size
, st
->codec
->sample_rate
},
171 if (st
->codec
->codec_type
== AVMEDIA_TYPE_VIDEO
) {
172 /* FIXME: We should round down here... */
173 if (st
->avg_frame_rate
.num
> 0 && st
->avg_frame_rate
.den
> 0) {
174 s
->max_frames_per_packet
= av_rescale_q(s1
->max_delay
,
175 (AVRational
){1, 1000000},
176 av_inv_q(st
->avg_frame_rate
));
178 s
->max_frames_per_packet
= 1;
182 avpriv_set_pts_info(st
, 32, 1, 90000);
183 switch(st
->codec
->codec_id
) {
184 case AV_CODEC_ID_MP2
:
185 case AV_CODEC_ID_MP3
:
186 s
->buf_ptr
= s
->buf
+ 4;
188 case AV_CODEC_ID_MPEG1VIDEO
:
189 case AV_CODEC_ID_MPEG2VIDEO
:
191 case AV_CODEC_ID_MPEG2TS
:
192 n
= s
->max_payload_size
/ TS_PACKET_SIZE
;
195 s
->max_payload_size
= n
* TS_PACKET_SIZE
;
198 case AV_CODEC_ID_H264
:
199 /* check for H.264 MP4 syntax */
200 if (st
->codec
->extradata_size
> 4 && st
->codec
->extradata
[0] == 1) {
201 s
->nal_length_size
= (st
->codec
->extradata
[4] & 0x03) + 1;
204 case AV_CODEC_ID_HEVC
:
205 /* Only check for the standardized hvcC version of extradata, keeping
206 * things simple and similar to the avcC/H264 case above, instead
207 * of trying to handle the pre-standardization versions (as in
208 * libavcodec/hevc.c). */
209 if (st
->codec
->extradata_size
> 21 && st
->codec
->extradata
[0] == 1) {
210 s
->nal_length_size
= (st
->codec
->extradata
[21] & 0x03) + 1;
213 case AV_CODEC_ID_VORBIS
:
214 case AV_CODEC_ID_THEORA
:
215 if (!s
->max_frames_per_packet
) s
->max_frames_per_packet
= 15;
216 s
->max_frames_per_packet
= av_clip(s
->max_frames_per_packet
, 1, 15);
217 s
->max_payload_size
-= 6; // ident+frag+tdt/vdt+pkt_num+pkt_length
220 case AV_CODEC_ID_ADPCM_G722
:
221 /* Due to a historical error, the clock rate for G722 in RTP is
222 * 8000, even if the sample rate is 16000. See RFC 3551. */
223 avpriv_set_pts_info(st
, 32, 1, 8000);
225 case AV_CODEC_ID_OPUS
:
226 if (st
->codec
->channels
> 2) {
227 av_log(s1
, AV_LOG_ERROR
, "Multistream opus not supported in RTP\n");
230 /* The opus RTP RFC says that all opus streams should use 48000 Hz
231 * as clock rate, since all opus sample rates can be expressed in
232 * this clock rate, and sample rate changes on the fly are supported. */
233 avpriv_set_pts_info(st
, 32, 1, 48000);
235 case AV_CODEC_ID_ILBC
:
236 if (st
->codec
->block_align
!= 38 && st
->codec
->block_align
!= 50) {
237 av_log(s1
, AV_LOG_ERROR
, "Incorrect iLBC block size specified\n");
240 if (!s
->max_frames_per_packet
)
241 s
->max_frames_per_packet
= 1;
242 s
->max_frames_per_packet
= FFMIN(s
->max_frames_per_packet
,
243 s
->max_payload_size
/ st
->codec
->block_align
);
245 case AV_CODEC_ID_AMR_NB
:
246 case AV_CODEC_ID_AMR_WB
:
247 if (!s
->max_frames_per_packet
)
248 s
->max_frames_per_packet
= 12;
249 if (st
->codec
->codec_id
== AV_CODEC_ID_AMR_NB
)
253 /* max_header_toc_size + the largest AMR payload must fit */
254 if (1 + s
->max_frames_per_packet
+ n
> s
->max_payload_size
) {
255 av_log(s1
, AV_LOG_ERROR
, "RTP max payload size too small for AMR\n");
258 if (st
->codec
->channels
!= 1) {
259 av_log(s1
, AV_LOG_ERROR
, "Only mono is supported\n");
262 case AV_CODEC_ID_AAC
:
266 if (st
->codec
->codec_type
== AVMEDIA_TYPE_AUDIO
) {
267 avpriv_set_pts_info(st
, 32, 1, st
->codec
->sample_rate
);
277 return AVERROR(EINVAL
);
280 /* send an rtcp sender report packet */
281 static void rtcp_send_sr(AVFormatContext
*s1
, int64_t ntp_time
, int bye
)
283 RTPMuxContext
*s
= s1
->priv_data
;
286 av_dlog(s1
, "RTCP: %02x %"PRIx64
" %x\n", s
->payload_type
, ntp_time
, s
->timestamp
);
288 s
->last_rtcp_ntp_time
= ntp_time
;
289 rtp_ts
= av_rescale_q(ntp_time
- s
->first_rtcp_ntp_time
, (AVRational
){1, 1000000},
290 s1
->streams
[0]->time_base
) + s
->base_timestamp
;
291 avio_w8(s1
->pb
, RTP_VERSION
<< 6);
292 avio_w8(s1
->pb
, RTCP_SR
);
293 avio_wb16(s1
->pb
, 6); /* length in words - 1 */
294 avio_wb32(s1
->pb
, s
->ssrc
);
295 avio_wb64(s1
->pb
, NTP_TO_RTP_FORMAT(ntp_time
));
296 avio_wb32(s1
->pb
, rtp_ts
);
297 avio_wb32(s1
->pb
, s
->packet_count
);
298 avio_wb32(s1
->pb
, s
->octet_count
);
301 int len
= FFMIN(strlen(s
->cname
), 255);
302 avio_w8(s1
->pb
, (RTP_VERSION
<< 6) + 1);
303 avio_w8(s1
->pb
, RTCP_SDES
);
304 avio_wb16(s1
->pb
, (7 + len
+ 3) / 4); /* length in words - 1 */
306 avio_wb32(s1
->pb
, s
->ssrc
);
307 avio_w8(s1
->pb
, 0x01); /* CNAME */
308 avio_w8(s1
->pb
, len
);
309 avio_write(s1
->pb
, s
->cname
, len
);
310 avio_w8(s1
->pb
, 0); /* END */
311 for (len
= (7 + len
) % 4; len
% 4; len
++)
316 avio_w8(s1
->pb
, (RTP_VERSION
<< 6) | 1);
317 avio_w8(s1
->pb
, RTCP_BYE
);
318 avio_wb16(s1
->pb
, 1); /* length in words - 1 */
319 avio_wb32(s1
->pb
, s
->ssrc
);
325 /* send an rtp packet. sequence number is incremented, but the caller
326 must update the timestamp itself */
327 void ff_rtp_send_data(AVFormatContext
*s1
, const uint8_t *buf1
, int len
, int m
)
329 RTPMuxContext
*s
= s1
->priv_data
;
331 av_dlog(s1
, "rtp_send_data size=%d\n", len
);
333 /* build the RTP header */
334 avio_w8(s1
->pb
, RTP_VERSION
<< 6);
335 avio_w8(s1
->pb
, (s
->payload_type
& 0x7f) | ((m
& 0x01) << 7));
336 avio_wb16(s1
->pb
, s
->seq
);
337 avio_wb32(s1
->pb
, s
->timestamp
);
338 avio_wb32(s1
->pb
, s
->ssrc
);
340 avio_write(s1
->pb
, buf1
, len
);
343 s
->seq
= (s
->seq
+ 1) & 0xffff;
344 s
->octet_count
+= len
;
348 /* send an integer number of samples and compute time stamp and fill
349 the rtp send buffer before sending. */
350 static int rtp_send_samples(AVFormatContext
*s1
,
351 const uint8_t *buf1
, int size
, int sample_size_bits
)
353 RTPMuxContext
*s
= s1
->priv_data
;
354 int len
, max_packet_size
, n
;
355 /* Calculate the number of bytes to get samples aligned on a byte border */
356 int aligned_samples_size
= sample_size_bits
/av_gcd(sample_size_bits
, 8);
358 max_packet_size
= (s
->max_payload_size
/ aligned_samples_size
) * aligned_samples_size
;
359 /* Not needed, but who knows. Don't check if samples aren't an even number of bytes. */
360 if ((sample_size_bits
% 8) == 0 && ((8 * size
) % sample_size_bits
) != 0)
361 return AVERROR(EINVAL
);
365 len
= FFMIN(max_packet_size
, size
);
368 memcpy(s
->buf_ptr
, buf1
, len
);
372 s
->timestamp
= s
->cur_timestamp
+ n
* 8 / sample_size_bits
;
373 ff_rtp_send_data(s1
, s
->buf
, s
->buf_ptr
- s
->buf
, 0);
374 n
+= (s
->buf_ptr
- s
->buf
);
379 static void rtp_send_mpegaudio(AVFormatContext
*s1
,
380 const uint8_t *buf1
, int size
)
382 RTPMuxContext
*s
= s1
->priv_data
;
383 int len
, count
, max_packet_size
;
385 max_packet_size
= s
->max_payload_size
;
387 /* test if we must flush because not enough space */
388 len
= (s
->buf_ptr
- s
->buf
);
389 if ((len
+ size
) > max_packet_size
) {
391 ff_rtp_send_data(s1
, s
->buf
, s
->buf_ptr
- s
->buf
, 0);
392 s
->buf_ptr
= s
->buf
+ 4;
395 if (s
->buf_ptr
== s
->buf
+ 4) {
396 s
->timestamp
= s
->cur_timestamp
;
400 if (size
> max_packet_size
) {
401 /* big packet: fragment */
404 len
= max_packet_size
- 4;
407 /* build fragmented packet */
410 s
->buf
[2] = count
>> 8;
412 memcpy(s
->buf
+ 4, buf1
, len
);
413 ff_rtp_send_data(s1
, s
->buf
, len
+ 4, 0);
419 if (s
->buf_ptr
== s
->buf
+ 4) {
420 /* no fragmentation possible */
426 memcpy(s
->buf_ptr
, buf1
, size
);
431 static void rtp_send_raw(AVFormatContext
*s1
,
432 const uint8_t *buf1
, int size
)
434 RTPMuxContext
*s
= s1
->priv_data
;
435 int len
, max_packet_size
;
437 max_packet_size
= s
->max_payload_size
;
440 len
= max_packet_size
;
444 s
->timestamp
= s
->cur_timestamp
;
445 ff_rtp_send_data(s1
, buf1
, len
, (len
== size
));
452 /* NOTE: size is assumed to be an integer multiple of TS_PACKET_SIZE */
453 static void rtp_send_mpegts_raw(AVFormatContext
*s1
,
454 const uint8_t *buf1
, int size
)
456 RTPMuxContext
*s
= s1
->priv_data
;
459 while (size
>= TS_PACKET_SIZE
) {
460 len
= s
->max_payload_size
- (s
->buf_ptr
- s
->buf
);
463 memcpy(s
->buf_ptr
, buf1
, len
);
468 out_len
= s
->buf_ptr
- s
->buf
;
469 if (out_len
>= s
->max_payload_size
) {
470 ff_rtp_send_data(s1
, s
->buf
, out_len
, 0);
476 static int rtp_send_ilbc(AVFormatContext
*s1
, const uint8_t *buf
, int size
)
478 RTPMuxContext
*s
= s1
->priv_data
;
479 AVStream
*st
= s1
->streams
[0];
480 int frame_duration
= av_get_audio_frame_duration(st
->codec
, 0);
481 int frame_size
= st
->codec
->block_align
;
482 int frames
= size
/ frame_size
;
485 int n
= FFMIN(s
->max_frames_per_packet
- s
->num_frames
, frames
);
487 if (!s
->num_frames
) {
489 s
->timestamp
= s
->cur_timestamp
;
491 memcpy(s
->buf_ptr
, buf
, n
* frame_size
);
494 s
->buf_ptr
+= n
* frame_size
;
495 buf
+= n
* frame_size
;
496 s
->cur_timestamp
+= n
* frame_duration
;
498 if (s
->num_frames
== s
->max_frames_per_packet
) {
499 ff_rtp_send_data(s1
, s
->buf
, s
->buf_ptr
- s
->buf
, 1);
506 static int rtp_write_packet(AVFormatContext
*s1
, AVPacket
*pkt
)
508 RTPMuxContext
*s
= s1
->priv_data
;
509 AVStream
*st
= s1
->streams
[0];
513 av_dlog(s1
, "%d: write len=%d\n", pkt
->stream_index
, size
);
515 rtcp_bytes
= ((s
->octet_count
- s
->last_octet_count
) * RTCP_TX_RATIO_NUM
) /
517 if ((s
->first_packet
|| ((rtcp_bytes
>= RTCP_SR_SIZE
) &&
518 (ff_ntp_time() - s
->last_rtcp_ntp_time
> 5000000))) &&
519 !(s
->flags
& FF_RTP_FLAG_SKIP_RTCP
)) {
520 rtcp_send_sr(s1
, ff_ntp_time(), 0);
521 s
->last_octet_count
= s
->octet_count
;
524 s
->cur_timestamp
= s
->base_timestamp
+ pkt
->pts
;
526 switch(st
->codec
->codec_id
) {
527 case AV_CODEC_ID_PCM_MULAW
:
528 case AV_CODEC_ID_PCM_ALAW
:
529 case AV_CODEC_ID_PCM_U8
:
530 case AV_CODEC_ID_PCM_S8
:
531 return rtp_send_samples(s1
, pkt
->data
, size
, 8 * st
->codec
->channels
);
532 case AV_CODEC_ID_PCM_U16BE
:
533 case AV_CODEC_ID_PCM_U16LE
:
534 case AV_CODEC_ID_PCM_S16BE
:
535 case AV_CODEC_ID_PCM_S16LE
:
536 return rtp_send_samples(s1
, pkt
->data
, size
, 16 * st
->codec
->channels
);
537 case AV_CODEC_ID_ADPCM_G722
:
538 /* The actual sample size is half a byte per sample, but since the
539 * stream clock rate is 8000 Hz while the sample rate is 16000 Hz,
540 * the correct parameter for send_samples_bits is 8 bits per stream
542 return rtp_send_samples(s1
, pkt
->data
, size
, 8 * st
->codec
->channels
);
543 case AV_CODEC_ID_ADPCM_G726
:
544 return rtp_send_samples(s1
, pkt
->data
, size
,
545 st
->codec
->bits_per_coded_sample
* st
->codec
->channels
);
546 case AV_CODEC_ID_MP2
:
547 case AV_CODEC_ID_MP3
:
548 rtp_send_mpegaudio(s1
, pkt
->data
, size
);
550 case AV_CODEC_ID_MPEG1VIDEO
:
551 case AV_CODEC_ID_MPEG2VIDEO
:
552 ff_rtp_send_mpegvideo(s1
, pkt
->data
, size
);
554 case AV_CODEC_ID_AAC
:
555 if (s
->flags
& FF_RTP_FLAG_MP4A_LATM
)
556 ff_rtp_send_latm(s1
, pkt
->data
, size
);
558 ff_rtp_send_aac(s1
, pkt
->data
, size
);
560 case AV_CODEC_ID_AMR_NB
:
561 case AV_CODEC_ID_AMR_WB
:
562 ff_rtp_send_amr(s1
, pkt
->data
, size
);
564 case AV_CODEC_ID_MPEG2TS
:
565 rtp_send_mpegts_raw(s1
, pkt
->data
, size
);
567 case AV_CODEC_ID_H264
:
568 ff_rtp_send_h264(s1
, pkt
->data
, size
);
570 case AV_CODEC_ID_H261
:
571 ff_rtp_send_h261(s1
, pkt
->data
, size
);
573 case AV_CODEC_ID_H263
:
574 if (s
->flags
& FF_RTP_FLAG_RFC2190
) {
575 int mb_info_size
= 0;
576 const uint8_t *mb_info
=
577 av_packet_get_side_data(pkt
, AV_PKT_DATA_H263_MB_INFO
,
580 av_log(s1
, AV_LOG_ERROR
, "failed to allocate side data\n");
581 return AVERROR(ENOMEM
);
583 ff_rtp_send_h263_rfc2190(s1
, pkt
->data
, size
, mb_info
, mb_info_size
);
587 case AV_CODEC_ID_H263P
:
588 ff_rtp_send_h263(s1
, pkt
->data
, size
);
590 case AV_CODEC_ID_HEVC
:
591 ff_rtp_send_hevc(s1
, pkt
->data
, size
);
593 case AV_CODEC_ID_VORBIS
:
594 case AV_CODEC_ID_THEORA
:
595 ff_rtp_send_xiph(s1
, pkt
->data
, size
);
597 case AV_CODEC_ID_VP8
:
598 ff_rtp_send_vp8(s1
, pkt
->data
, size
);
600 case AV_CODEC_ID_ILBC
:
601 rtp_send_ilbc(s1
, pkt
->data
, size
);
603 case AV_CODEC_ID_MJPEG
:
604 ff_rtp_send_jpeg(s1
, pkt
->data
, size
);
606 case AV_CODEC_ID_OPUS
:
607 if (size
> s
->max_payload_size
) {
608 av_log(s1
, AV_LOG_ERROR
,
609 "Packet size %d too large for max RTP payload size %d\n",
610 size
, s
->max_payload_size
);
611 return AVERROR(EINVAL
);
613 /* Intentional fallthrough */
615 /* better than nothing : send the codec raw data */
616 rtp_send_raw(s1
, pkt
->data
, size
);
622 static int rtp_write_trailer(AVFormatContext
*s1
)
624 RTPMuxContext
*s
= s1
->priv_data
;
626 /* If the caller closes and recreates ->pb, this might actually
627 * be NULL here even if it was successfully allocated at the start. */
628 if (s1
->pb
&& (s
->flags
& FF_RTP_FLAG_SEND_BYE
))
629 rtcp_send_sr(s1
, ff_ntp_time(), 1);
635 AVOutputFormat ff_rtp_muxer
= {
637 .long_name
= NULL_IF_CONFIG_SMALL("RTP output"),
638 .priv_data_size
= sizeof(RTPMuxContext
),
639 .audio_codec
= AV_CODEC_ID_PCM_MULAW
,
640 .video_codec
= AV_CODEC_ID_MPEG4
,
641 .write_header
= rtp_write_header
,
642 .write_packet
= rtp_write_packet
,
643 .write_trailer
= rtp_write_trailer
,
644 .priv_class
= &rtp_muxer_class
,