# rtprtxsend

See GstRtpRtxReceive for examples

The purpose of the sender RTX object is to keep a history of RTP packets up to a configurable limit (max-size-time or max-size-packets). It will listen for upstream custom retransmission events (GstRTPRetransmissionRequest) that comes from downstream (#GstRtpSession). When receiving a request it will look up the requested seqnum in its list of stored packets. If the packet is available, it will create a RTX packet according to RFC 4588 and send this as an auxiliary stream. RTX is SSRC-multiplexed

## Hierarchy

    GObject
        ╰──GInitiallyUnowned
            ╰──GstObject
                ╰──GstElement
                    ╰──rtprtxsend

## Factory details

Authors: – Julien Isorce

Classification: – `Codec`

Rank – none

Plugin – rtpmanager

Package – GStreamer Good Plug-ins

## Pad Templates

### `sink`

    application/x-rtp:

Presence – always

Direction – sink

Object type – GstPad

### `src`

    application/x-rtp:

Presence – always

Direction – src

Object type – GstPad

## Properties

### clock-rate-map

    “clock-rate-map” GstStructure *

Map of payload types to their clock rates

Flags : Read / Write

### max-size-packets

    “max-size-packets” guint

Amount of packets to queue (0 = unlimited)

Flags : Read / Write

Default value : 100

### max-size-time

    “max-size-time” guint

Amount of ms to queue (0 = unlimited)

Flags : Read / Write

Default value : 0

### num-rtx-packets

    “num-rtx-packets” guint

Number of retransmission packets sent

Flags : Read

Default value : 0

### num-rtx-requests

    “num-rtx-requests” guint

Number of retransmission events received

Flags : Read

Default value : 0

### payload-type-map

    “payload-type-map” GstStructure *

Map of original payload types to their retransmission payload types

Flags : Read / Write

### ssrc-map

    “ssrc-map” GstStructure *

Map of SSRCs to their retransmission SSRCs for SSRC-multiplexed mode (default = random)

Flags : Read / Write

The results of the search are