FFmpeg
rtp.c
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1 /*
2  * RTP input/output format
3  * Copyright (c) 2002 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 
22 #include "libavutil/avstring.h"
23 #include "libavutil/opt.h"
24 #include "avformat.h"
25 
26 #include "rtp.h"
27 
28 /* from http://www.iana.org/assignments/rtp-parameters last updated 05 January 2005 */
29 /* payload types >= 96 are dynamic;
30  * payload types between 72 and 76 are reserved for RTCP conflict avoidance;
31  * all the other payload types not present in the table are unassigned or
32  * reserved
33  */
34 static const struct {
35  int pt;
36  const char enc_name[6];
37  enum AVMediaType codec_type;
38  enum AVCodecID codec_id;
39  int clock_rate;
40  int audio_channels;
41 } rtp_payload_types[] = {
42  {0, "PCMU", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_PCM_MULAW, 8000, 1},
43  {3, "GSM", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 8000, 1},
44  {4, "G723", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_G723_1, 8000, 1},
45  {5, "DVI4", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 8000, 1},
46  {6, "DVI4", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 16000, 1},
47  {7, "LPC", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 8000, 1},
48  {8, "PCMA", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_PCM_ALAW, 8000, 1},
49  {9, "G722", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_ADPCM_G722, 8000, 1},
50  {10, "L16", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_PCM_S16BE, 44100, 2},
51  {11, "L16", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_PCM_S16BE, 44100, 1},
52  {12, "QCELP", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_QCELP, 8000, 1},
53  {13, "CN", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 8000, 1},
54  {14, "MPA", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_MP2, -1, -1},
55  {14, "MPA", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_MP3, -1, -1},
56  {15, "G728", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 8000, 1},
57  {16, "DVI4", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 11025, 1},
58  {17, "DVI4", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 22050, 1},
59  {18, "G729", AVMEDIA_TYPE_AUDIO, AV_CODEC_ID_NONE, 8000, 1},
60  {25, "CelB", AVMEDIA_TYPE_VIDEO, AV_CODEC_ID_NONE, 90000, -1},
61  {26, "JPEG", AVMEDIA_TYPE_VIDEO, AV_CODEC_ID_MJPEG, 90000, -1},
62  {28, "nv", AVMEDIA_TYPE_VIDEO, AV_CODEC_ID_NONE, 90000, -1},
63  {31, "H261", AVMEDIA_TYPE_VIDEO, AV_CODEC_ID_H261, 90000, -1},
64  {32, "MPV", AVMEDIA_TYPE_VIDEO, AV_CODEC_ID_MPEG1VIDEO, 90000, -1},
65  {32, "MPV", AVMEDIA_TYPE_VIDEO, AV_CODEC_ID_MPEG2VIDEO, 90000, -1},
66  {33, "MP2T", AVMEDIA_TYPE_DATA, AV_CODEC_ID_MPEG2TS, 90000, -1},
67  {34, "H263", AVMEDIA_TYPE_VIDEO, AV_CODEC_ID_H263, 90000, -1},
68  {-1, "", AVMEDIA_TYPE_UNKNOWN, AV_CODEC_ID_NONE, -1, -1}
69 };
70 
71 int ff_rtp_get_codec_info(AVCodecParameters *par, int payload_type)
72 {
73  int i = 0;
74 
75  for (i = 0; rtp_payload_types[i].pt >= 0; i++)
76  if (rtp_payload_types[i].pt == payload_type) {
77  if (rtp_payload_types[i].codec_id != AV_CODEC_ID_NONE) {
78  par->codec_type = rtp_payload_types[i].codec_type;
79  par->codec_id = rtp_payload_types[i].codec_id;
80  if (rtp_payload_types[i].audio_channels > 0) {
81  av_channel_layout_uninit(&par->ch_layout);
82  par->ch_layout.order = AV_CHANNEL_ORDER_UNSPEC;
83  par->ch_layout.nb_channels = rtp_payload_types[i].audio_channels;
84  }
85  if (rtp_payload_types[i].clock_rate > 0)
86  par->sample_rate = rtp_payload_types[i].clock_rate;
87  return 0;
88  }
89  }
90  return -1;
91 }
92 
93 int ff_rtp_get_payload_type(const AVFormatContext *fmt,
94  const AVCodecParameters *par, int idx)
95 {
96  int i;
97  const AVOutputFormat *ofmt = fmt ? fmt->oformat : NULL;
98 
99  /* Was the payload type already specified for the RTP muxer? */
100  if (ofmt && ofmt->priv_class && fmt->priv_data) {
101  int64_t payload_type;
102  if (av_opt_get_int(fmt->priv_data, "payload_type", 0, &payload_type) >= 0 &&
103  payload_type >= 0)
104  return (int)payload_type;
105  }
106 
107  /* static payload type */
108  for (i = 0; rtp_payload_types[i].pt >= 0; ++i)
109  if (rtp_payload_types[i].codec_id == par->codec_id) {
110  if (par->codec_id == AV_CODEC_ID_H263 && (!fmt || !fmt->oformat ||
111  !fmt->oformat->priv_class || !fmt->priv_data ||
112  !av_opt_flag_is_set(fmt->priv_data, "rtpflags", "rfc2190")))
113  continue;
114  /* G722 has 8000 as nominal rate even if the sample rate is 16000,
115  * see section 4.5.2 in RFC 3551. */
116  if (par->codec_id == AV_CODEC_ID_ADPCM_G722 &&
117  par->sample_rate == 16000 && par->ch_layout.nb_channels == 1)
118  return rtp_payload_types[i].pt;
119  if (par->codec_type == AVMEDIA_TYPE_AUDIO &&
120  ((rtp_payload_types[i].clock_rate > 0 &&
121  par->sample_rate != rtp_payload_types[i].clock_rate) ||
122  (rtp_payload_types[i].audio_channels > 0 &&
123  par->ch_layout.nb_channels != rtp_payload_types[i].audio_channels)))
124  continue;
125  return rtp_payload_types[i].pt;
126  }
127 
128  if (idx < 0)
129  idx = par->codec_type == AVMEDIA_TYPE_AUDIO;
130 
131  /* dynamic payload type */
132  return RTP_PT_PRIVATE + idx;
133 }
134 
135 const char *ff_rtp_enc_name(int payload_type)
136 {
137  int i;
138 
139  for (i = 0; rtp_payload_types[i].pt >= 0; i++)
140  if (rtp_payload_types[i].pt == payload_type)
141  return rtp_payload_types[i].enc_name;
142 
143  return "";
144 }
145 
146 enum AVCodecID ff_rtp_codec_id(const char *buf, enum AVMediaType codec_type)
147 {
148  int i;
149 
150  for (i = 0; rtp_payload_types[i].pt >= 0; i++)
151  if (!av_strcasecmp(buf, rtp_payload_types[i].enc_name) && (codec_type == rtp_payload_types[i].codec_type))
152  return rtp_payload_types[i].codec_id;
153 
154  return AV_CODEC_ID_NONE;
155 }
opt.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
ff_rtp_codec_id
enum AVCodecID ff_rtp_codec_id(const char *buf, enum AVMediaType codec_type)
Return the codec id for the given encoding name and codec type.
Definition: rtp.c:146
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
av_strcasecmp
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:207
audio_channels
int audio_channels
Definition: rtp.c:40
clock_rate
int clock_rate
Definition: rtp.c:39
rtp_payload_types
static const struct @326 rtp_payload_types[]
enc_name
const char enc_name[6]
Definition: rtp.c:36
AV_CODEC_ID_ADPCM_G722
@ AV_CODEC_ID_ADPCM_G722
Definition: codec_id.h:397
AVChannelLayout::order
enum AVChannelOrder order
Channel order used in this layout.
Definition: channel_layout.h:312
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:317
codec_type
enum AVMediaType codec_type
Definition: rtp.c:37
AV_CODEC_ID_H261
@ AV_CODEC_ID_H261
Definition: codec_id.h:55
AV_CODEC_ID_PCM_S16BE
@ AV_CODEC_ID_PCM_S16BE
Definition: codec_id.h:331
AV_CODEC_ID_MP3
@ AV_CODEC_ID_MP3
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: codec_id.h:443
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
codec_id
enum AVCodecID codec_id
Definition: rtp.c:38
AV_CHANNEL_ORDER_UNSPEC
@ AV_CHANNEL_ORDER_UNSPEC
Only the channel count is specified, without any further information about the channel order.
Definition: channel_layout.h:112
AV_CODEC_ID_MP2
@ AV_CODEC_ID_MP2
Definition: codec_id.h:442
AV_CODEC_ID_PCM_MULAW
@ AV_CODEC_ID_PCM_MULAW
Definition: codec_id.h:336
AVMEDIA_TYPE_DATA
@ AVMEDIA_TYPE_DATA
Opaque data information usually continuous.
Definition: avutil.h:203
AVFormatContext
Format I/O context.
Definition: avformat.h:1115
AV_CODEC_ID_PCM_ALAW
@ AV_CODEC_ID_PCM_ALAW
Definition: codec_id.h:337
RTP_PT_PRIVATE
#define RTP_PT_PRIVATE
Definition: rtp.h:79
NULL
#define NULL
Definition: coverity.c:32
AV_CODEC_ID_G723_1
@ AV_CODEC_ID_G723_1
Definition: codec_id.h:494
AV_CODEC_ID_MPEG2TS
@ AV_CODEC_ID_MPEG2TS
FAKE codec to indicate a raw MPEG-2 TS stream (only used by libavformat)
Definition: codec_id.h:596
AVOutputFormat::priv_class
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:539
av_opt_get_int
int av_opt_get_int(void *obj, const char *name, int search_flags, int64_t *out_val)
Definition: opt.c:978
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:206
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:171
AV_CODEC_ID_MPEG1VIDEO
@ AV_CODEC_ID_MPEG1VIDEO
Definition: codec_id.h:53
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:49
AV_CODEC_ID_QCELP
@ AV_CODEC_ID_QCELP
Definition: codec_id.h:466
AVMediaType
AVMediaType
Definition: avutil.h:199
AV_CODEC_ID_H263
@ AV_CODEC_ID_H263
Definition: codec_id.h:56
AVMEDIA_TYPE_UNKNOWN
@ AVMEDIA_TYPE_UNKNOWN
Usually treated as AVMEDIA_TYPE_DATA.
Definition: avutil.h:200
ff_rtp_get_codec_info
int ff_rtp_get_codec_info(AVCodecParameters *par, int payload_type)
Initialize a codec context based on the payload type.
Definition: rtp.c:71
pt
int pt
Definition: rtp.c:35
rtp.h
AV_CODEC_ID_MJPEG
@ AV_CODEC_ID_MJPEG
Definition: codec_id.h:59
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
AVOutputFormat
Definition: avformat.h:510
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AVFormatContext::oformat
const struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1134
avformat.h
av_channel_layout_uninit
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
Free any allocated data in the channel layout and reset the channel count to 0.
Definition: channel_layout.c:640
av_opt_flag_is_set
int av_opt_flag_is_set(void *obj, const char *field_name, const char *flag_name)
Check whether a particular flag is set in a flags field.
Definition: opt.c:1137
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
ff_rtp_enc_name
const char * ff_rtp_enc_name(int payload_type)
Return the encoding name (as defined in http://www.iana.org/assignments/rtp-parameters) for a given p...
Definition: rtp.c:135
avstring.h
AV_CODEC_ID_MPEG2VIDEO
@ AV_CODEC_ID_MPEG2VIDEO
preferred ID for MPEG-1/2 video decoding
Definition: codec_id.h:54
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1143
ff_rtp_get_payload_type
int ff_rtp_get_payload_type(const AVFormatContext *fmt, const AVCodecParameters *par, int idx)
Return the payload type for a given stream used in the given format context.
Definition: rtp.c:93
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