libavformat/rtpdec.h

   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 #ifndef AVFORMAT_RTPDEC_H
  23 #define AVFORMAT_RTPDEC_H
  24
  25 #include "libavcodec/avcodec.h"
  26 #include "avformat.h"
  27 #include "rtp.h"
  28
  29 /** Structure listing useful vars to parse RTP packet payload*/
  30 typedef struct rtp_payload_data
  31 {
  32     int sizelength;
  33     int indexlength;
  34     int indexdeltalength;
  35     int profile_level_id;
  36     int streamtype;
  37     int objecttype;
  38     char *mode;
  39
  40     /** mpeg 4 AU headers */
  41     struct AUHeaders {
  42         int size;
  43         int index;
  44         int cts_flag;
  45         int cts;
  46         int dts_flag;
  47         int dts;
  48         int rap_flag;
  49         int streamstate;
  50     } *au_headers;
  51     int nb_au_headers;
  52     int au_headers_length_bytes;
  53     int cur_au_index;
  54 } RTPPayloadData;
  55
  56 typedef struct PayloadContext PayloadContext;
  57 typedef struct RTPDynamicProtocolHandler_s RTPDynamicProtocolHandler;
  58
  59 #define RTP_MIN_PACKET_LENGTH 12
  60 #define RTP_MAX_PACKET_LENGTH 1500 /* XXX: suppress this define */
  61
  62 typedef struct RTPDemuxContext RTPDemuxContext;
  63 RTPDemuxContext *rtp_parse_open(AVFormatContext *s1, AVStream *st, URLContext *rtpc, int payload_type, RTPPayloadData *rtp_payload_data);
  64 void rtp_parse_set_dynamic_protocol(RTPDemuxContext *s, PayloadContext *ctx,
  65                                     RTPDynamicProtocolHandler *handler);
  66 int rtp_parse_packet(RTPDemuxContext *s, AVPacket *pkt,
  67                      const uint8_t *buf, int len);
  68 void rtp_parse_close(RTPDemuxContext *s);
  69
  70 int rtp_get_local_port(URLContext *h);
  71 int rtp_set_remote_url(URLContext *h, const char *uri);
  72 #if (LIBAVFORMAT_VERSION_MAJOR <= 52)
  73 void rtp_get_file_handles(URLContext *h, int *prtp_fd, int *prtcp_fd);
  74 #endif
  75
  76 /**
  77  * Send a dummy packet on both port pairs to set up the connection
  78  * state in potential NAT routers, so that we're able to receive
  79  * packets.
  80  *
  81  * Note, this only works if the NAT router doesn't remap ports. This
  82  * isn't a standardized procedure, but it works in many cases in practice.
  83  *
  84  * The same routine is used with RDT too, even if RDT doesn't use normal
  85  * RTP packets otherwise.
  86  */
  87 void rtp_send_punch_packets(URLContext* rtp_handle);
  88
  89 /**
  90  * some rtp servers assume client is dead if they don't hear from them...
  91  * so we send a Receiver Report to the provided ByteIO context
  92  * (we don't have access to the rtcp handle from here)
  93  */
  94 int rtp_check_and_send_back_rr(RTPDemuxContext *s, int count);
  95
  96 // these statistics are used for rtcp receiver reports...
  97 typedef struct {
  98     uint16_t max_seq;           ///< highest sequence number seen
  99     uint32_t cycles;            ///< shifted count of sequence number cycles
 100     uint32_t base_seq;          ///< base sequence number
 101     uint32_t bad_seq;           ///< last bad sequence number + 1
 102     int probation;              ///< sequence packets till source is valid
 103     int received;               ///< packets received
 104     int expected_prior;         ///< packets expected in last interval
 105     int received_prior;         ///< packets received in last interval
 106     uint32_t transit;           ///< relative transit time for previous packet
 107     uint32_t jitter;            ///< estimated jitter.
 108 } RTPStatistics;
 109
 110 #define RTP_FLAG_KEY    0x1 ///< RTP packet contains a keyframe
 111 #define RTP_FLAG_MARKER 0x2 ///< RTP marker bit was set for this packet
 112 /**
 113  * Packet parsing for "private" payloads in the RTP specs.
 114  *
 115  * @param ctx RTSP demuxer context
 116  * @param s stream context
 117  * @param st stream that this packet belongs to
 118  * @param pkt packet in which to write the parsed data
 119  * @param timestamp pointer in which to write the timestamp of this RTP packet
 120  * @param buf pointer to raw RTP packet data
 121  * @param len length of buf
 122  * @param flags flags from the RTP packet header (RTP_FLAG_*)
 123  */
 124 typedef int (*DynamicPayloadPacketHandlerProc) (AVFormatContext *ctx,
 125                                                 PayloadContext *s,
 126                                                 AVStream *st,
 127                                                 AVPacket * pkt,
 128                                                 uint32_t *timestamp,
 129                                                 const uint8_t * buf,
 130                                                 int len, int flags);
 131
 132 struct RTPDynamicProtocolHandler_s {
 133     // fields from AVRtpDynamicPayloadType_s
 134     const char enc_name[50];    /* XXX: still why 50 ? ;-) */
 135     enum AVMediaType codec_type;
 136     enum CodecID codec_id;
 137
 138     // may be null
 139     int (*parse_sdp_a_line) (AVFormatContext *s,
 140                              int st_index,
 141                              PayloadContext *priv_data,
 142                              const char *line); ///< Parse the a= line from the sdp field
 143     PayloadContext *(*open) (void); ///< allocate any data needed by the rtp parsing for this dynamic data.
 144     void (*close)(PayloadContext *protocol_data); ///< free any data needed by the rtp parsing for this dynamic data.
 145     DynamicPayloadPacketHandlerProc parse_packet; ///< parse handler for this dynamic packet.
 146
 147     struct RTPDynamicProtocolHandler_s *next;
 148 };
 149
 150 // moved out of rtp.c, because the h264 decoder needs to know about this structure..
 151 struct RTPDemuxContext {
 152     AVFormatContext *ic;
 153     AVStream *st;
 154     int payload_type;
 155     uint32_t ssrc;
 156     uint16_t seq;
 157     uint32_t timestamp;
 158     uint32_t base_timestamp;
 159     uint32_t cur_timestamp;
 160     int max_payload_size;
 161     struct MpegTSContext *ts;   /* only used for MP2T payloads */
 162     int read_buf_index;
 163     int read_buf_size;
 164     /* used to send back RTCP RR */
 165     URLContext *rtp_ctx;
 166     char hostname[256];
 167
 168     RTPStatistics statistics; ///< Statistics for this stream (used by RTCP receiver reports)
 169
 170     /* rtcp sender statistics receive */
 171     int64_t last_rtcp_ntp_time;    // TODO: move into statistics
 172     uint32_t last_rtcp_timestamp;  // TODO: move into statistics
 173
 174     /* rtcp sender statistics */
 175     unsigned int packet_count;     // TODO: move into statistics (outgoing)
 176     unsigned int octet_count;      // TODO: move into statistics (outgoing)
 177     unsigned int last_octet_count; // TODO: move into statistics (outgoing)
 178     int first_packet;
 179     /* buffer for output */
 180     uint8_t buf[RTP_MAX_PACKET_LENGTH];
 181     uint8_t *buf_ptr;
 182
 183     /* special infos for au headers parsing */
 184     RTPPayloadData *rtp_payload_data; // TODO: Move into dynamic payload handlers
 185
 186     /* dynamic payload stuff */
 187     DynamicPayloadPacketHandlerProc parse_packet;     ///< This is also copied from the dynamic protocol handler structure
 188     PayloadContext *dynamic_protocol_context;        ///< This is a copy from the values setup from the sdp parsing, in rtsp.c don't free me.
 189     int max_frames_per_packet;
 190 };
 191
 192 extern RTPDynamicProtocolHandler *RTPFirstDynamicPayloadHandler;
 193 void ff_register_dynamic_payload_handler(RTPDynamicProtocolHandler *handler);
 194
 195 int ff_rtsp_next_attr_and_value(const char **p, char *attr, int attr_size, char *value, int value_size); ///< from rtsp.c, but used by rtp dynamic protocol handlers.
 196
 197 void av_register_rtp_dynamic_payload_handlers(void);
 198
 199 #endif /* AVFORMAT_RTPDEC_H */