PeerStreamer

/*

 * RTP demuxer definitions

 * Copyright (c) 2002 Fabrice Bellard

 * Copyright (c) 2006 Ryan Martell <rdm4@martellventures.com>

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#ifndef AVFORMAT_RTPDEC_H

#define AVFORMAT_RTPDEC_H

#include "libavcodec/avcodec.h"

#include "avformat.h"

#include "rtp.h"

/** Structure listing useful vars to parse RTP packet payload*/

typedef struct rtp_payload_data

{

    int sizelength;

    int indexlength;

    int indexdeltalength;

    int profile_level_id;

    int streamtype;

    int objecttype;

    char *mode;

    /** mpeg 4 AU headers */

    struct AUHeaders {

        int size;

        int index;

        int cts_flag;

        int cts;

        int dts_flag;

        int dts;

        int rap_flag;

        int streamstate;

    } *au_headers;

    int au_headers_allocated;

    int nb_au_headers;

    int au_headers_length_bytes;

    int cur_au_index;

} RTPPayloadData;

typedef struct PayloadContext PayloadContext;

typedef struct RTPDynamicProtocolHandler_s RTPDynamicProtocolHandler;

#define RTP_MIN_PACKET_LENGTH 12

#define RTP_MAX_PACKET_LENGTH 1500 /* XXX: suppress this define */

typedef struct RTPDemuxContext RTPDemuxContext;

RTPDemuxContext *rtp_parse_open(AVFormatContext *s1, AVStream *st, URLContext *rtpc, int payload_type, RTPPayloadData *rtp_payload_data);

void rtp_parse_set_dynamic_protocol(RTPDemuxContext *s, PayloadContext *ctx,

                                    RTPDynamicProtocolHandler *handler);

int rtp_parse_packet(RTPDemuxContext *s, AVPacket *pkt,

                     const uint8_t *buf, int len);

void rtp_parse_close(RTPDemuxContext *s);

#if (LIBAVFORMAT_VERSION_MAJOR <= 53)

int rtp_get_local_port(URLContext *h);

#endif

int rtp_get_local_rtp_port(URLContext *h);

int rtp_get_local_rtcp_port(URLContext *h);

int rtp_set_remote_url(URLContext *h, const char *uri);

#if (LIBAVFORMAT_VERSION_MAJOR <= 52)

void rtp_get_file_handles(URLContext *h, int *prtp_fd, int *prtcp_fd);

#endif

/**

 * Send a dummy packet on both port pairs to set up the connection

 * state in potential NAT routers, so that we're able to receive

 * packets.

 *

 * Note, this only works if the NAT router doesn't remap ports. This

 * isn't a standardized procedure, but it works in many cases in practice.

 *

 * The same routine is used with RDT too, even if RDT doesn't use normal

 * RTP packets otherwise.

 */

void rtp_send_punch_packets(URLContext* rtp_handle);

/**

 * some rtp servers assume client is dead if they don't hear from them...

 * so we send a Receiver Report to the provided ByteIO context

 * (we don't have access to the rtcp handle from here)

 */

int rtp_check_and_send_back_rr(RTPDemuxContext *s, int count);

// these statistics are used for rtcp receiver reports...

typedef struct {

    uint16_t max_seq;           ///< highest sequence number seen

    uint32_t cycles;            ///< shifted count of sequence number cycles

    uint32_t base_seq;          ///< base sequence number

    uint32_t bad_seq;           ///< last bad sequence number + 1

    int probation;              ///< sequence packets till source is valid

    int received;               ///< packets received

    int expected_prior;         ///< packets expected in last interval

    int received_prior;         ///< packets received in last interval

    uint32_t transit;           ///< relative transit time for previous packet

    uint32_t jitter;            ///< estimated jitter.

} RTPStatistics;

#define RTP_FLAG_KEY    0x1 ///< RTP packet contains a keyframe

#define RTP_FLAG_MARKER 0x2 ///< RTP marker bit was set for this packet

/**

 * Packet parsing for "private" payloads in the RTP specs.

 *

 * @param ctx RTSP demuxer context

 * @param s stream context

 * @param st stream that this packet belongs to

 * @param pkt packet in which to write the parsed data

 * @param timestamp pointer in which to write the timestamp of this RTP packet

 * @param buf pointer to raw RTP packet data

 * @param len length of buf

 * @param flags flags from the RTP packet header (RTP_FLAG_*)

 */

typedef int (*DynamicPayloadPacketHandlerProc) (AVFormatContext *ctx,

                                                PayloadContext *s,

                                                AVStream *st,

                                                AVPacket * pkt,

                                                uint32_t *timestamp,

                                                const uint8_t * buf,

                                                int len, int flags);

struct RTPDynamicProtocolHandler_s {

    // fields from AVRtpDynamicPayloadType_s

    const char enc_name[50];    /* XXX: still why 50 ? ;-) */

    enum AVMediaType codec_type;

    enum CodecID codec_id;

    // may be null

    int (*parse_sdp_a_line) (AVFormatContext *s,

                             int st_index,

                             PayloadContext *priv_data,

                             const char *line); ///< Parse the a= line from the sdp field

    PayloadContext *(*open) (void); ///< allocate any data needed by the rtp parsing for this dynamic data.

    void (*close)(PayloadContext *protocol_data); ///< free any data needed by the rtp parsing for this dynamic data.

    DynamicPayloadPacketHandlerProc parse_packet; ///< parse handler for this dynamic packet.

    struct RTPDynamicProtocolHandler_s *next;

};

// moved out of rtp.c, because the h264 decoder needs to know about this structure..

struct RTPDemuxContext {

    AVFormatContext *ic;

    AVStream *st;

    int payload_type;

    uint32_t ssrc;

    uint16_t seq;

    uint32_t timestamp;

    uint32_t base_timestamp;

    uint32_t cur_timestamp;

    int64_t  range_start_offset;

    int max_payload_size;

    struct MpegTSContext *ts;   /* only used for MP2T payloads */

    int read_buf_index;

    int read_buf_size;

    /* used to send back RTCP RR */

    URLContext *rtp_ctx;

    char hostname[256];

    RTPStatistics statistics; ///< Statistics for this stream (used by RTCP receiver reports)

    /* rtcp sender statistics receive */

    int64_t last_rtcp_ntp_time;    // TODO: move into statistics

    int64_t first_rtcp_ntp_time;   // TODO: move into statistics

    uint32_t last_rtcp_timestamp;  // TODO: move into statistics

    /* rtcp sender statistics */

    unsigned int packet_count;     // TODO: move into statistics (outgoing)

    unsigned int octet_count;      // TODO: move into statistics (outgoing)

    unsigned int last_octet_count; // TODO: move into statistics (outgoing)

    int first_packet;

    /* buffer for output */

    uint8_t buf[RTP_MAX_PACKET_LENGTH];

    uint8_t *buf_ptr;

    /* special infos for au headers parsing */

    RTPPayloadData *rtp_payload_data; // TODO: Move into dynamic payload handlers

    /* dynamic payload stuff */

    DynamicPayloadPacketHandlerProc parse_packet;     ///< This is also copied from the dynamic protocol handler structure

    PayloadContext *dynamic_protocol_context;        ///< This is a copy from the values setup from the sdp parsing, in rtsp.c don't free me.

    int max_frames_per_packet;

};

extern RTPDynamicProtocolHandler *RTPFirstDynamicPayloadHandler;

void ff_register_dynamic_payload_handler(RTPDynamicProtocolHandler *handler);

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.

void av_register_rtp_dynamic_payload_handlers(void);

#endif /* AVFORMAT_RTPDEC_H */