FFmpeg
rtpenc_chain.c
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1 /*
2  * RTP muxer chaining code
3  * Copyright (c) 2010 Martin Storsjo
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 
22 #include "avformat.h"
23 #include "avio_internal.h"
24 #include "rtpenc_chain.h"
25 #include "rtp.h"
26 #include "libavutil/opt.h"
27 
29  AVStream *st, URLContext *handle, int packet_size,
30  int idx)
31 {
32  AVFormatContext *rtpctx = NULL;
33  int ret;
34  const AVOutputFormat *rtp_format = av_guess_format("rtp", NULL, NULL);
35  uint8_t *rtpflags;
37 
38  if (!rtp_format) {
39  ret = AVERROR(ENOSYS);
40  goto fail;
41  }
42 
43  /* Allocate an AVFormatContext for each output stream */
44  rtpctx = avformat_alloc_context();
45  if (!rtpctx) {
46  ret = AVERROR(ENOMEM);
47  goto fail;
48  }
49 
50  rtpctx->oformat = rtp_format;
51  if (!avformat_new_stream(rtpctx, NULL)) {
52  ret = AVERROR(ENOMEM);
53  goto fail;
54  }
55  /* Pass the interrupt callback on */
56  rtpctx->interrupt_callback = s->interrupt_callback;
57  /* Copy the max delay setting; the rtp muxer reads this. */
58  rtpctx->max_delay = s->max_delay;
59  /* Copy other stream parameters. */
61  rtpctx->flags |= s->flags & AVFMT_FLAG_BITEXACT;
62  rtpctx->strict_std_compliance = s->strict_std_compliance;
63 
64  /* Get the payload type from the codec */
65  if (st->id < RTP_PT_PRIVATE)
66  rtpctx->streams[0]->id =
68  else
69  rtpctx->streams[0]->id = st->id;
70 
71 
72  if (av_opt_get(s, "rtpflags", AV_OPT_SEARCH_CHILDREN, &rtpflags) >= 0)
73  av_dict_set(&opts, "rtpflags", rtpflags, AV_DICT_DONT_STRDUP_VAL);
74 
75  /* Set the synchronized start time. */
76  rtpctx->start_time_realtime = s->start_time_realtime;
77 
79  rtpctx->streams[0]->time_base = st->time_base;
80 
81  if (handle) {
82  ret = ffio_fdopen(&rtpctx->pb, handle);
83  if (ret < 0)
84  ffurl_close(handle);
85  } else
86  ret = ffio_open_dyn_packet_buf(&rtpctx->pb, packet_size);
87  if (!ret)
88  ret = avformat_write_header(rtpctx, &opts);
90 
91  if (ret) {
92  if (handle && rtpctx->pb) {
93  avio_closep(&rtpctx->pb);
94  } else if (rtpctx->pb) {
95  ffio_free_dyn_buf(&rtpctx->pb);
96  }
97  avformat_free_context(rtpctx);
98  return ret;
99  }
100 
101  *out = rtpctx;
102  return 0;
103 
104 fail:
105  avformat_free_context(rtpctx);
106  if (handle)
107  ffurl_close(handle);
108  return ret;
109 }
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4375
out
FILE * out
Definition: movenc.c:54
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1175
AVFormatContext::strict_std_compliance
int strict_std_compliance
Allow non-standard and experimental extension.
Definition: avformat.h:1404
ffurl_close
int ffurl_close(URLContext *h)
Definition: avio.c:461
AVDictionary
Definition: dict.c:30
ff_rtp_get_payload_type
int ff_rtp_get_payload_type(AVFormatContext *fmt, AVCodecParameters *par, int idx)
Return the payload type for a given stream used in the given format context.
Definition: rtp.c:90
AVFormatContext::interrupt_callback
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1374
RTPMuxContext::st
AVStream * st
Definition: rtpenc.h:30
fail
#define fail()
Definition: checkasm.h:136
rtpenc_chain.h
AV_DICT_DONT_STRDUP_VAL
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:72
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVFormatContext::flags
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1225
avformat_write_header
av_warn_unused_result int avformat_write_header(AVFormatContext *s, AVDictionary **options)
Allocate the stream private data and write the stream header to an output media file.
Definition: mux.c:469
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
opts
AVDictionary * opts
Definition: movenc.c:50
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
RTP_PT_PRIVATE
#define RTP_PT_PRIVATE
Definition: rtp.h:79
AVStream::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:870
NULL
#define NULL
Definition: coverity.c:32
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1149
avformat_alloc_context
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
Definition: options.c:166
AVStream::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:903
AV_OPT_SEARCH_CHILDREN
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:559
ffio_open_dyn_packet_buf
int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
Open a write only packetized memory stream with a maximum packet size of 'max_packet_size'.
Definition: aviobuf.c:1367
av_dict_free
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values.
Definition: dict.c:203
rtp.h
avcodec_parameters_copy
int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src)
Copy the contents of src to dst.
Definition: codec_par.c:72
avio_closep
int avio_closep(AVIOContext **s)
Close the resource accessed by the AVIOContext *s, free it and set the pointer pointing to it to NULL...
Definition: aviobuf.c:1175
ffio_fdopen
int ffio_fdopen(AVIOContext **s, URLContext *h)
Create and initialize a AVIOContext for accessing the resource referenced by the URLContext h.
Definition: aviobuf.c:904
URLContext
Definition: url.h:38
AVOutputFormat
Definition: avformat.h:495
avio_internal.h
AVFormatContext::max_delay
int max_delay
Definition: avformat.h:1219
ffio_free_dyn_buf
void ffio_free_dyn_buf(AVIOContext **s)
Free a dynamic buffer.
Definition: aviobuf.c:1437
AVStream::id
int id
Format-specific stream ID.
Definition: avformat.h:854
AVFMT_FLAG_BITEXACT
#define AVFMT_FLAG_BITEXACT
When muxing, try to avoid writing any random/volatile data to the output.
Definition: avformat.h:1242
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:847
AVFormatContext::oformat
const struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1126
avformat.h
ff_rtp_chain_mux_open
int ff_rtp_chain_mux_open(AVFormatContext **out, AVFormatContext *s, AVStream *st, URLContext *handle, int packet_size, int idx)
Definition: rtpenc_chain.c:28
avformat_free_context
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: utils.c:4302
av_guess_format
const AVOutputFormat * av_guess_format(const char *short_name, const char *filename, const char *mime_type)
Return the output format in the list of registered output formats which best matches the provided par...
Definition: format.c:51
AVFormatContext::start_time_realtime
int64_t start_time_realtime
Start time of the stream in real world time, in microseconds since the Unix epoch (00:00 1st January ...
Definition: avformat.h:1349
av_dict_set
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
av_opt_get
int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
Definition: opt.c:779