| 1 | /* |
| 2 | * RTP definitions |
| 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 | #ifndef AVFORMAT_RTP_H |
| 22 | #define AVFORMAT_RTP_H |
| 23 | |
| 24 | #include "libavformat/avformat.h" |
| 25 | #include "libavcodec/avcodec.h" |
| 26 | #include "libavutil/mathematics.h" |
| 27 | |
| 28 | /** |
| 29 | * Return the payload type for a given stream used in the given format context. |
| 30 | * Static payload types are derived from the codec. |
| 31 | * Dynamic payload type are derived from the id field in AVStream. |
| 32 | * The format context private option payload_type overrides both. |
| 33 | * |
| 34 | * @param fmt The context of the format |
| 35 | * @param codec The context of the codec |
| 36 | * @param idx The stream index |
| 37 | * @return The payload type (the 'PT' field in the RTP header). |
| 38 | */ |
| 39 | int ff_rtp_get_payload_type(AVFormatContext *fmt, AVCodecContext *codec, |
| 40 | int idx); |
| 41 | |
| 42 | /** |
| 43 | * Initialize a codec context based on the payload type. |
| 44 | * |
| 45 | * Fill the codec_type and codec_id fields of a codec context with |
| 46 | * information depending on the payload type; for audio codecs, the |
| 47 | * channels and sample_rate fields are also filled. |
| 48 | * |
| 49 | * @param codec The context of the codec |
| 50 | * @param payload_type The payload type (the 'PT' field in the RTP header) |
| 51 | * @return In case of unknown payload type or dynamic payload type, a |
| 52 | * negative value is returned; otherwise, 0 is returned |
| 53 | */ |
| 54 | int ff_rtp_get_codec_info(AVCodecContext *codec, int payload_type); |
| 55 | |
| 56 | /** |
| 57 | * Return the encoding name (as defined in |
| 58 | * http://www.iana.org/assignments/rtp-parameters) for a given payload type. |
| 59 | * |
| 60 | * @param payload_type The payload type (the 'PT' field in the RTP header) |
| 61 | * @return In case of unknown payload type or dynamic payload type, a pointer |
| 62 | * to an empty string is returned; otherwise, a pointer to a string containing |
| 63 | * the encoding name is returned |
| 64 | */ |
| 65 | const char *ff_rtp_enc_name(int payload_type); |
| 66 | |
| 67 | /** |
| 68 | * Return the codec id for the given encoding name and codec type. |
| 69 | * |
| 70 | * @param buf A pointer to the string containing the encoding name |
| 71 | * @param codec_type The codec type |
| 72 | * @return In case of unknown encoding name, AV_CODEC_ID_NONE is returned; |
| 73 | * otherwise, the codec id is returned |
| 74 | */ |
| 75 | enum AVCodecID ff_rtp_codec_id(const char *buf, enum AVMediaType codec_type); |
| 76 | |
| 77 | #define RTP_PT_PRIVATE 96 |
| 78 | #define RTP_VERSION 2 |
| 79 | #define RTP_MAX_SDES 256 /**< maximum text length for SDES */ |
| 80 | |
| 81 | /* RTCP packets use 0.5% of the bandwidth */ |
| 82 | #define RTCP_TX_RATIO_NUM 5 |
| 83 | #define RTCP_TX_RATIO_DEN 1000 |
| 84 | |
| 85 | /* An arbitrary id value for RTP Xiph streams - only relevant to indicate |
| 86 | * that the configuration has changed within a stream (by changing the |
| 87 | * ident value sent). |
| 88 | */ |
| 89 | #define RTP_XIPH_IDENT 0xfecdba |
| 90 | |
| 91 | /* RTCP packet types */ |
| 92 | enum RTCPType { |
| 93 | RTCP_FIR = 192, |
| 94 | RTCP_NACK, // 193 |
| 95 | RTCP_SMPTETC,// 194 |
| 96 | RTCP_IJ, // 195 |
| 97 | RTCP_SR = 200, |
| 98 | RTCP_RR, // 201 |
| 99 | RTCP_SDES, // 202 |
| 100 | RTCP_BYE, // 203 |
| 101 | RTCP_APP, // 204 |
| 102 | RTCP_RTPFB,// 205 |
| 103 | RTCP_PSFB, // 206 |
| 104 | RTCP_XR, // 207 |
| 105 | RTCP_AVB, // 208 |
| 106 | RTCP_RSI, // 209 |
| 107 | RTCP_TOKEN,// 210 |
| 108 | }; |
| 109 | |
| 110 | #define RTP_PT_IS_RTCP(x) (((x) >= RTCP_FIR && (x) <= RTCP_IJ) || \ |
| 111 | ((x) >= RTCP_SR && (x) <= RTCP_TOKEN)) |
| 112 | |
| 113 | #define NTP_TO_RTP_FORMAT(x) av_rescale((x), INT64_C(1) << 32, 1000000) |
| 114 | |
| 115 | #endif /* AVFORMAT_RTP_H */ |