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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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/opt.h>
23 #include "avformat.h"
24 
25 #include "rtp.h"
26 
27 //#define DEBUG
28 
29 /* from http://www.iana.org/assignments/rtp-parameters last updated 05 January 2005 */
30 /* payload types >= 96 are dynamic;
31  * payload types between 72 and 76 are reserved for RTCP conflict avoidance;
32  * all the other payload types not present in the table are unassigned or
33  * reserved
34  */
35 static const struct
36 {
37  int pt;
38  const char enc_name[6];
44 {
45  {0, "PCMU", AVMEDIA_TYPE_AUDIO, CODEC_ID_PCM_MULAW, 8000, 1},
46  {3, "GSM", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 8000, 1},
47  {4, "G723", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 8000, 1},
48  {5, "DVI4", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 8000, 1},
49  {6, "DVI4", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 16000, 1},
50  {7, "LPC", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 8000, 1},
51  {8, "PCMA", AVMEDIA_TYPE_AUDIO, CODEC_ID_PCM_ALAW, 8000, 1},
52  {9, "G722", AVMEDIA_TYPE_AUDIO, CODEC_ID_ADPCM_G722, 8000, 1},
53  {10, "L16", AVMEDIA_TYPE_AUDIO, CODEC_ID_PCM_S16BE, 44100, 2},
54  {11, "L16", AVMEDIA_TYPE_AUDIO, CODEC_ID_PCM_S16BE, 44100, 1},
55  {12, "QCELP", AVMEDIA_TYPE_AUDIO, CODEC_ID_QCELP, 8000, 1},
56  {13, "CN", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 8000, 1},
57  {14, "MPA", AVMEDIA_TYPE_AUDIO, CODEC_ID_MP2, -1, -1},
58  {14, "MPA", AVMEDIA_TYPE_AUDIO, CODEC_ID_MP3, -1, -1},
59  {15, "G728", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 8000, 1},
60  {16, "DVI4", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 11025, 1},
61  {17, "DVI4", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 22050, 1},
62  {18, "G729", AVMEDIA_TYPE_AUDIO, CODEC_ID_NONE, 8000, 1},
63  {25, "CelB", AVMEDIA_TYPE_VIDEO, CODEC_ID_NONE, 90000, -1},
64  {26, "JPEG", AVMEDIA_TYPE_VIDEO, CODEC_ID_MJPEG, 90000, -1},
65  {28, "nv", AVMEDIA_TYPE_VIDEO, CODEC_ID_NONE, 90000, -1},
66  {31, "H261", AVMEDIA_TYPE_VIDEO, CODEC_ID_H261, 90000, -1},
67  {32, "MPV", AVMEDIA_TYPE_VIDEO, CODEC_ID_MPEG1VIDEO, 90000, -1},
68  {32, "MPV", AVMEDIA_TYPE_VIDEO, CODEC_ID_MPEG2VIDEO, 90000, -1},
69  {33, "MP2T", AVMEDIA_TYPE_DATA, CODEC_ID_MPEG2TS, 90000, -1},
70  {34, "H263", AVMEDIA_TYPE_VIDEO, CODEC_ID_H263, 90000, -1},
71  {-1, "", AVMEDIA_TYPE_UNKNOWN, CODEC_ID_NONE, -1, -1}
72 };
73 
74 int ff_rtp_get_codec_info(AVCodecContext *codec, int payload_type)
75 {
76  int i = 0;
77 
78  for (i = 0; AVRtpPayloadTypes[i].pt >= 0; i++)
79  if (AVRtpPayloadTypes[i].pt == payload_type) {
81  codec->codec_type = AVRtpPayloadTypes[i].codec_type;
82  codec->codec_id = AVRtpPayloadTypes[i].codec_id;
84  codec->channels = AVRtpPayloadTypes[i].audio_channels;
85  if (AVRtpPayloadTypes[i].clock_rate > 0)
86  codec->sample_rate = AVRtpPayloadTypes[i].clock_rate;
87  return 0;
88  }
89  }
90  return -1;
91 }
92 
94 {
95  int i;
96  AVOutputFormat *ofmt = fmt ? fmt->oformat : NULL;
97 
98  /* Was the payload type already specified for the RTP muxer? */
99  if (ofmt && ofmt->priv_class) {
100  int64_t payload_type;
101  if (av_opt_get_int(fmt->priv_data, "payload_type", 0, &payload_type) >= 0 &&
102  payload_type >= 0)
103  return (int)payload_type;
104  }
105 
106  /* static payload type */
107  for (i = 0; AVRtpPayloadTypes[i].pt >= 0; ++i)
108  if (AVRtpPayloadTypes[i].codec_id == codec->codec_id) {
109  if (codec->codec_id == CODEC_ID_H263)
110  continue;
111  if (codec->codec_id == CODEC_ID_PCM_S16BE)
112  if (codec->channels != AVRtpPayloadTypes[i].audio_channels)
113  continue;
114  return AVRtpPayloadTypes[i].pt;
115  }
116 
117  /* dynamic payload type */
118  return RTP_PT_PRIVATE + (codec->codec_type == AVMEDIA_TYPE_AUDIO);
119 }
120 
121 const char *ff_rtp_enc_name(int payload_type)
122 {
123  int i;
124 
125  for (i = 0; AVRtpPayloadTypes[i].pt >= 0; i++)
126  if (AVRtpPayloadTypes[i].pt == payload_type) {
127  return AVRtpPayloadTypes[i].enc_name;
128  }
129 
130  return "";
131 }
132 
133 enum CodecID ff_rtp_codec_id(const char *buf, enum AVMediaType codec_type)
134 {
135  int i;
136 
137  for (i = 0; AVRtpPayloadTypes[i].pt >= 0; i++)
138  if (!strcmp(buf, AVRtpPayloadTypes[i].enc_name) && (codec_type == AVRtpPayloadTypes[i].codec_type)){
139  return AVRtpPayloadTypes[i].codec_id;
140  }
141 
142  return CODEC_ID_NONE;
143 }