status-go/vendor/github.com/pion/rtcp/rapid_resynchronization_req...

91 lines
2.5 KiB
Go

package rtcp
import (
"encoding/binary"
"fmt"
)
// The RapidResynchronizationRequest packet informs the encoder about the loss of an undefined amount of coded video data belonging to one or more pictures
type RapidResynchronizationRequest struct {
// SSRC of sender
SenderSSRC uint32
// SSRC of the media source
MediaSSRC uint32
}
// RapidResynchronisationRequest is provided as RFC 6051 spells resynchronization with an s.
// We provide both names to be consistent with other RFCs which spell resynchronization with a z.
type RapidResynchronisationRequest = RapidResynchronizationRequest
const (
rrrLength = 2
rrrHeaderLength = ssrcLength * 2
rrrMediaOffset = 4
)
// Marshal encodes the RapidResynchronizationRequest in binary
func (p RapidResynchronizationRequest) Marshal() ([]byte, error) {
/*
* RRR does not require parameters. Therefore, the length field MUST be
* 2, and there MUST NOT be any Feedback Control Information.
*
* The semantics of this FB message is independent of the payload type.
*/
rawPacket := make([]byte, p.len())
packetBody := rawPacket[headerLength:]
binary.BigEndian.PutUint32(packetBody, p.SenderSSRC)
binary.BigEndian.PutUint32(packetBody[rrrMediaOffset:], p.MediaSSRC)
hData, err := p.Header().Marshal()
if err != nil {
return nil, err
}
copy(rawPacket, hData)
return rawPacket, nil
}
// Unmarshal decodes the RapidResynchronizationRequest from binary
func (p *RapidResynchronizationRequest) Unmarshal(rawPacket []byte) error {
if len(rawPacket) < (headerLength + (ssrcLength * 2)) {
return errPacketTooShort
}
var h Header
if err := h.Unmarshal(rawPacket); err != nil {
return err
}
if h.Type != TypeTransportSpecificFeedback || h.Count != FormatRRR {
return errWrongType
}
p.SenderSSRC = binary.BigEndian.Uint32(rawPacket[headerLength:])
p.MediaSSRC = binary.BigEndian.Uint32(rawPacket[headerLength+ssrcLength:])
return nil
}
func (p *RapidResynchronizationRequest) len() int {
return headerLength + rrrHeaderLength
}
// Header returns the Header associated with this packet.
func (p *RapidResynchronizationRequest) Header() Header {
return Header{
Count: FormatRRR,
Type: TypeTransportSpecificFeedback,
Length: rrrLength,
}
}
// DestinationSSRC returns an array of SSRC values that this packet refers to.
func (p *RapidResynchronizationRequest) DestinationSSRC() []uint32 {
return []uint32{p.MediaSSRC}
}
func (p *RapidResynchronizationRequest) String() string {
return fmt.Sprintf("RapidResynchronizationRequest %x %x", p.SenderSSRC, p.MediaSSRC)
}