libavformat/rtp.c

   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_G728, 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 }