FFmpeg
rtpdec.h
Go to the documentation of this file.
1 /*
2  * RTP demuxer definitions
3  * Copyright (c) 2002 Fabrice Bellard
4  * Copyright (c) 2006 Ryan Martell <rdm4@martellventures.com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #ifndef AVFORMAT_RTPDEC_H
24 #define AVFORMAT_RTPDEC_H
25 
26 #include "libavcodec/avcodec.h"
27 #include "avformat.h"
28 #include "rtp.h"
29 #include "url.h"
30 #include "srtp.h"
31 
32 typedef struct PayloadContext PayloadContext;
34 
35 #define RTP_MIN_PACKET_LENGTH 12
36 #define RTP_MAX_PACKET_LENGTH 8192
37 
38 #define RTP_REORDER_QUEUE_DEFAULT_SIZE 500
39 
40 #define RTP_NOTS_VALUE ((uint32_t)-1)
41 
42 typedef struct RTPDemuxContext RTPDemuxContext;
44  int payload_type, int queue_size);
48  const char *params);
50  uint8_t **buf, int len);
54 
55 /**
56  * Send a dummy packet on both port pairs to set up the connection
57  * state in potential NAT routers, so that we're able to receive
58  * packets.
59  *
60  * Note, this only works if the NAT router doesn't remap ports. This
61  * isn't a standardized procedure, but it works in many cases in practice.
62  *
63  * The same routine is used with RDT too, even if RDT doesn't use normal
64  * RTP packets otherwise.
65  */
66 void ff_rtp_send_punch_packets(URLContext* rtp_handle);
67 
68 /**
69  * some rtp servers assume client is dead if they don't hear from them...
70  * so we send a Receiver Report to the provided URLContext or AVIOContext
71  * (we don't have access to the rtcp handle from here)
72  */
74  AVIOContext *avio, int count);
76  AVIOContext *avio);
77 
78 // these statistics are used for rtcp receiver reports...
79 typedef struct RTPStatistics {
80  uint16_t max_seq; ///< highest sequence number seen
81  uint32_t cycles; ///< shifted count of sequence number cycles
82  uint32_t base_seq; ///< base sequence number
83  uint32_t bad_seq; ///< last bad sequence number + 1
84  int probation; ///< sequence packets till source is valid
85  uint32_t received; ///< packets received
86  uint32_t expected_prior; ///< packets expected in last interval
87  uint32_t received_prior; ///< packets received in last interval
88  uint32_t transit; ///< relative transit time for previous packet
89  uint32_t jitter; ///< estimated jitter.
91 
92 #define RTP_FLAG_KEY 0x1 ///< RTP packet contains a keyframe
93 #define RTP_FLAG_MARKER 0x2 ///< RTP marker bit was set for this packet
94 /**
95  * Packet parsing for "private" payloads in the RTP specs.
96  *
97  * @param ctx RTSP demuxer context
98  * @param s stream context
99  * @param st stream that this packet belongs to
100  * @param pkt packet in which to write the parsed data
101  * @param timestamp pointer to the RTP timestamp of the input data, can be
102  * updated by the function if returning older, buffered data
103  * @param buf pointer to raw RTP packet data
104  * @param len length of buf
105  * @param seq RTP sequence number of the packet
106  * @param flags flags from the RTP packet header (RTP_FLAG_*)
107  */
109  PayloadContext *s,
110  AVStream *st, AVPacket *pkt,
111  uint32_t *timestamp,
112  const uint8_t * buf,
113  int len, uint16_t seq, int flags);
114 
116  const char *enc_name;
120  int static_payload_id; /* 0 means no payload id is set. 0 is a valid
121  * payload ID (PCMU), too, but that format doesn't
122  * require any custom depacketization code. */
124 
125  /** Initialize dynamic protocol handler, called after the full rtpmap line is parsed, may be null */
126  int (*init)(AVFormatContext *s, int st_index, PayloadContext *priv_data);
127  /** Parse the a= line from the sdp field */
129  PayloadContext *priv_data, const char *line);
130  /** Free any data needed by the rtp parsing for this dynamic data.
131  * Don't free the protocol_data pointer itself, that is freed by the
132  * caller. This is called even if the init method failed. */
133  void (*close)(PayloadContext *protocol_data);
134  /** Parse handler for this dynamic packet */
137 };
138 
139 typedef struct RTPPacket {
140  uint16_t seq;
142  int len;
143  int64_t recvtime;
144  struct RTPPacket *next;
145 } RTPPacket;
146 
151  uint32_t ssrc;
152  uint16_t seq;
153  uint32_t timestamp;
154  uint32_t base_timestamp;
158  /* used to send back RTCP RR */
159  char hostname[256];
160 
163 
164  /** Statistics for this stream (used by RTCP receiver reports) */
166 
167  /** Fields for packet reordering @{ */
168  int prev_ret; ///< The return value of the actual parsing of the previous packet
169  RTPPacket* queue; ///< A sorted queue of buffered packets not yet returned
170  int queue_len; ///< The number of packets in queue
171  int queue_size; ///< The size of queue, or 0 if reordering is disabled
172  /*@}*/
173 
174  /* rtcp sender statistics receive */
179  int64_t rtcp_ts_offset;
180 
181  /* rtcp sender statistics */
182  unsigned int packet_count;
183  unsigned int octet_count;
184  unsigned int last_octet_count;
186 
187  /* dynamic payload stuff */
190 };
191 
192 /**
193  * Iterate over all registered rtp dynamic protocol handlers.
194  *
195  * @param opaque a pointer where libavformat will store the iteration state. Must
196  * point to NULL to start the iteration.
197  *
198  * @return the next registered rtp dynamic protocol handler or NULL when the iteration is
199  * finished
200  */
202 /**
203  * Find a registered rtp dynamic protocol handler with the specified name.
204  *
205  * @param name name of the requested rtp dynamic protocol handler
206  * @return A rtp dynamic protocol handler if one was found, NULL otherwise.
207  */
209  enum AVMediaType codec_type);
210 /**
211  * Find a registered rtp dynamic protocol handler with a matching codec ID.
212  *
213  * @param id AVCodecID of the requested rtp dynamic protocol handler.
214  * @return A rtp dynamic protocol handler if one was found, NULL otherwise.
215  */
217  enum AVMediaType codec_type);
218 
219 /* from rtsp.c, but used by rtp dynamic protocol handlers. */
220 int ff_rtsp_next_attr_and_value(const char **p, char *attr, int attr_size,
221  char *value, int value_size);
222 
224  AVStream *stream, PayloadContext *data, const char *p,
225  int (*parse_fmtp)(AVFormatContext *s,
226  AVStream *stream,
228  const char *attr, const char *value));
229 
230 /**
231  * Close the dynamic buffer and make a packet from it.
232  */
233 int ff_rtp_finalize_packet(AVPacket *pkt, AVIOContext **dyn_buf, int stream_idx);
234 
235 #endif /* AVFORMAT_RTPDEC_H */
RTPDynamicProtocolHandler::init
int(* init)(AVFormatContext *s, int st_index, PayloadContext *priv_data)
Initialize dynamic protocol handler, called after the full rtpmap line is parsed, may be null.
Definition: rtpdec.h:126
RTPStatistics
Definition: rtpdec.h:79
name
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option name
Definition: writing_filters.txt:88
RTPStatistics::expected_prior
uint32_t expected_prior
packets expected in last interval
Definition: rtpdec.h:86
RTPDynamicProtocolHandler::parse_sdp_a_line
int(* parse_sdp_a_line)(AVFormatContext *s, int st_index, PayloadContext *priv_data, const char *line)
Parse the a= line from the sdp field.
Definition: rtpdec.h:128
ff_rtp_parse_set_crypto
void ff_rtp_parse_set_crypto(RTPDemuxContext *s, const char *suite, const char *params)
Definition: rtpdec.c:618
RTPDynamicProtocolHandler::parse_packet
DynamicPayloadPacketHandlerProc parse_packet
Parse handler for this dynamic packet.
Definition: rtpdec.h:135
RTPDemuxContext::hostname
char hostname[256]
Definition: rtpdec.h:159
parse_fmtp
static int parse_fmtp(AVFormatContext *s, AVStream *stream, PayloadContext *data, const char *attr, const char *value)
Definition: rtpdec_latm.c:130
RTPDemuxContext::handler
const RTPDynamicProtocolHandler * handler
Definition: rtpdec.h:188
RTPDemuxContext::srtp
struct SRTPContext srtp
Definition: rtpdec.h:162
srtp.h
RTPDemuxContext::range_start_offset
int64_t range_start_offset
Definition: rtpdec.h:156
ff_rtp_reset_packet_queue
void ff_rtp_reset_packet_queue(RTPDemuxContext *s)
Definition: rtpdec.c:771
data
const char data[16]
Definition: mxf.c:142
SRTPContext
Definition: srtp.h:30
codec_type
enum AVMediaType codec_type
Definition: rtp.c:37
RTPDynamicProtocolHandler::codec_id
enum AVCodecID codec_id
Definition: rtpdec.h:118
RTPDynamicProtocolHandler::enc_name
const char * enc_name
Definition: rtpdec.h:116
ff_rtp_handler_find_by_name
const RTPDynamicProtocolHandler * ff_rtp_handler_find_by_name(const char *name, enum AVMediaType codec_type)
Find a registered rtp dynamic protocol handler with the specified name.
Definition: rtpdec.c:149
RTPStatistics::cycles
uint32_t cycles
shifted count of sequence number cycles
Definition: rtpdec.h:81
RTPDemuxContext::queue_size
int queue_size
The size of queue, or 0 if reordering is disabled.
Definition: rtpdec.h:171
RTPPacket::recvtime
int64_t recvtime
Definition: rtpdec.h:143
AVStreamParseType
AVStreamParseType
Definition: avformat.h:792
RTPDynamicProtocolHandler::close
void(* close)(PayloadContext *protocol_data)
Free any data needed by the rtp parsing for this dynamic data.
Definition: rtpdec.h:133
RTPPacket::buf
uint8_t * buf
Definition: rtpdec.h:141
RTPDynamicProtocolHandler::priv_data_size
int priv_data_size
Definition: rtpdec.h:123
ff_rtp_parse_set_dynamic_protocol
void ff_rtp_parse_set_dynamic_protocol(RTPDemuxContext *s, PayloadContext *ctx, const RTPDynamicProtocolHandler *handler)
Definition: rtpdec.c:611
RTPStatistics::jitter
uint32_t jitter
estimated jitter.
Definition: rtpdec.h:89
pkt
AVPacket * pkt
Definition: movenc.c:59
ff_rtp_parse_close
void ff_rtp_parse_close(RTPDemuxContext *s)
Definition: rtpdec.c:943
RTPDemuxContext::dynamic_protocol_context
PayloadContext * dynamic_protocol_context
Definition: rtpdec.h:189
RTPDemuxContext::payload_type
int payload_type
Definition: rtpdec.h:150
s
#define s(width, name)
Definition: cbs_vp9.c:257
RTPPacket::next
struct RTPPacket * next
Definition: rtpdec.h:144
RTPStatistics::received
uint32_t received
packets received
Definition: rtpdec.h:85
RTPDemuxContext::statistics
RTPStatistics statistics
Statistics for this stream (used by RTCP receiver reports)
Definition: rtpdec.h:165
s1
#define s1
Definition: regdef.h:38
RTPDemuxContext::last_rtcp_reception_time
int64_t last_rtcp_reception_time
Definition: rtpdec.h:176
RTPDemuxContext::queue
RTPPacket * queue
A sorted queue of buffered packets not yet returned.
Definition: rtpdec.h:169
ctx
AVFormatContext * ctx
Definition: movenc.c:48
ff_rtp_check_and_send_back_rr
int ff_rtp_check_and_send_back_rr(RTPDemuxContext *s, URLContext *fd, AVIOContext *avio, int count)
some rtp servers assume client is dead if they don't hear from them...
Definition: rtpdec.c:302
handler
static void handler(vbi_event *ev, void *user_data)
Definition: libzvbi-teletextdec.c:507
context
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option keep it simple and lowercase description are in without and describe what they for example set the foo of the bar offset is the offset of the field in your context
Definition: writing_filters.txt:91
AVFormatContext
Format I/O context.
Definition: avformat.h:1231
RTPDemuxContext::last_feedback_time
int64_t last_feedback_time
Definition: rtpdec.h:185
ff_rtsp_next_attr_and_value
int ff_rtsp_next_attr_and_value(const char **p, char *attr, int attr_size, char *value, int value_size)
RTPDemuxContext::queue_len
int queue_len
The number of packets in queue.
Definition: rtpdec.h:170
RTPStatistics::bad_seq
uint32_t bad_seq
last bad sequence number + 1
Definition: rtpdec.h:83
RTPDemuxContext::rtcp_ts_offset
int64_t rtcp_ts_offset
Definition: rtpdec.h:179
RTPDemuxContext::srtp_enabled
int srtp_enabled
Definition: rtpdec.h:161
RTPDemuxContext::last_rtcp_ntp_time
uint64_t last_rtcp_ntp_time
Definition: rtpdec.h:175
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:46
RTPPacket
Definition: rtpdec.h:139
suite
FFmpeg currently uses a custom build this text attempts to document some of its obscure features and options Makefile the full command issued by make and its output will be shown on the screen DBG Preprocess x86 external assembler files to a dbg asm file in the object which then gets compiled Helps in developing those assembler files DESTDIR Destination directory for the install useful to prepare packages or install FFmpeg in cross environments GEN Set to ‘1’ to generate the missing or mismatched references Makefile builds all the libraries and the executables fate Run the fate test suite
Definition: build_system.txt:28
RTPStatistics::transit
uint32_t transit
relative transit time for previous packet
Definition: rtpdec.h:88
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
AVMediaType
AVMediaType
Definition: avutil.h:199
RTPDemuxContext::first_rtcp_ntp_time
uint64_t first_rtcp_ntp_time
Definition: rtpdec.h:177
RTPDemuxContext::packet_count
unsigned int packet_count
Definition: rtpdec.h:182
ff_rtp_finalize_packet
int ff_rtp_finalize_packet(AVPacket *pkt, AVIOContext **dyn_buf, int stream_idx)
Close the dynamic buffer and make a packet from it.
Definition: rtpdec.c:988
RTPDemuxContext::unwrapped_timestamp
int64_t unwrapped_timestamp
Definition: rtpdec.h:155
RTPDynamicProtocolHandler::need_keyframe
int(* need_keyframe)(PayloadContext *context)
Definition: rtpdec.h:136
RTPDemuxContext::octet_count
unsigned int octet_count
Definition: rtpdec.h:183
ff_rtp_send_rtcp_feedback
int ff_rtp_send_rtcp_feedback(RTPDemuxContext *s, URLContext *fd, AVIOContext *avio)
Definition: rtpdec.c:459
rtp.h
RTPStatistics::max_seq
uint16_t max_seq
highest sequence number seen
Definition: rtpdec.h:80
ff_rtp_handler_iterate
const RTPDynamicProtocolHandler * ff_rtp_handler_iterate(void **opaque)
Iterate over all registered rtp dynamic protocol handlers.
Definition: rtpdec.c:138
URLContext
Definition: url.h:38
RTPDemuxContext::ssrc
uint32_t ssrc
Definition: rtpdec.h:151
RTPDynamicProtocolHandler::need_parsing
enum AVStreamParseType need_parsing
Definition: rtpdec.h:119
RTPDemuxContext::st
AVStream * st
Definition: rtpdec.h:149
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
url.h
uint8_t
uint8_t
Definition: audio_convert.c:194
RTPPacket::len
int len
Definition: rtpdec.h:142
RTPDemuxContext::max_payload_size
int max_payload_size
Definition: rtpdec.h:157
len
int len
Definition: vorbis_enc_data.h:452
RTPDemuxContext
Definition: rtpdec.h:147
RTPDemuxContext::timestamp
uint32_t timestamp
Definition: rtpdec.h:153
RTPStatistics::received_prior
uint32_t received_prior
packets received in last interval
Definition: rtpdec.h:87
DynamicPayloadPacketHandlerProc
int(* DynamicPayloadPacketHandlerProc)(AVFormatContext *ctx, PayloadContext *s, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags)
Packet parsing for "private" payloads in the RTP specs.
Definition: rtpdec.h:108
avcodec.h
RTPDemuxContext::ic
AVFormatContext * ic
Definition: rtpdec.h:148
AVStream
Stream structure.
Definition: avformat.h:873
RTPDemuxContext::seq
uint16_t seq
Definition: rtpdec.h:152
avformat.h
RTPStatistics::probation
int probation
sequence packets till source is valid
Definition: rtpdec.h:84
RTPDemuxContext::base_timestamp
uint32_t base_timestamp
Definition: rtpdec.h:154
RTPDynamicProtocolHandler::codec_type
enum AVMediaType codec_type
Definition: rtpdec.h:117
ff_rtp_handler_find_by_id
const RTPDynamicProtocolHandler * ff_rtp_handler_find_by_id(int id, enum AVMediaType codec_type)
Find a registered rtp dynamic protocol handler with a matching codec ID.
Definition: rtpdec.c:163
RTPPacket::seq
uint16_t seq
Definition: rtpdec.h:140
ff_parse_fmtp
int ff_parse_fmtp(AVFormatContext *s, AVStream *stream, PayloadContext *data, const char *p, int(*parse_fmtp)(AVFormatContext *s, AVStream *stream, PayloadContext *data, const char *attr, const char *value))
Definition: rtpdec.c:950
RTPDynamicProtocolHandler::static_payload_id
int static_payload_id
Definition: rtpdec.h:120
ff_rtp_queued_packet_time
int64_t ff_rtp_queued_packet_time(RTPDemuxContext *s)
Definition: rtpdec.c:816
RTPDemuxContext::last_rtcp_timestamp
uint32_t last_rtcp_timestamp
Definition: rtpdec.h:178
AVPacket
This structure stores compressed data.
Definition: packet.h:346
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
PayloadContext
RTP/JPEG specific private data.
Definition: rdt.c:83
int
int
Definition: ffmpeg_filter.c:158
RTPDemuxContext::prev_ret
int prev_ret
Fields for packet reordering.
Definition: rtpdec.h:168
ff_rtp_parse_open
RTPDemuxContext * ff_rtp_parse_open(AVFormatContext *s1, AVStream *st, int payload_type, int queue_size)
open a new RTP parse context for stream 'st'.
Definition: rtpdec.c:564
RTPStatistics::base_seq
uint32_t base_seq
base sequence number
Definition: rtpdec.h:82
line
The official guide to swscale for confused that consecutive non overlapping rectangles of slice_bottom special converter These generally are unscaled converters of common like for each output line the vertical scaler pulls lines from a ring buffer When the ring buffer does not contain the wanted line
Definition: swscale.txt:40
ff_rtp_parse_packet
int ff_rtp_parse_packet(RTPDemuxContext *s, AVPacket *pkt, uint8_t **buf, int len)
Parse an RTP or RTCP packet directly sent as a buffer.
Definition: rtpdec.c:930
RTPDynamicProtocolHandler
Definition: rtpdec.h:115
ff_rtp_send_punch_packets
void ff_rtp_send_punch_packets(URLContext *rtp_handle)
Send a dummy packet on both port pairs to set up the connection state in potential NAT routers,...
Definition: rtpdec.c:405
RTPDemuxContext::last_octet_count
unsigned int last_octet_count
Definition: rtpdec.h:184