40 lines
1.3 KiB
Go
40 lines
1.3 KiB
Go
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package rtp
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import (
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"encoding/binary"
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)
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const (
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// transport-wide sequence
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transportCCExtensionSize = 2
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)
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// TransportCCExtension is a extension payload format in
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// https://tools.ietf.org/html/draft-holmer-rmcat-transport-wide-cc-extensions-01
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// 0 1 2 3
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// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | 0xBE | 0xDE | length=1 |
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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// | ID | L=1 |transport-wide sequence number | zero padding |
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// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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type TransportCCExtension struct {
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TransportSequence uint16
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}
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// Marshal serializes the members to buffer
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func (t *TransportCCExtension) Marshal() ([]byte, error) {
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buf := make([]byte, transportCCExtensionSize)
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binary.BigEndian.PutUint16(buf[0:2], t.TransportSequence)
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return buf, nil
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}
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// Unmarshal parses the passed byte slice and stores the result in the members
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func (t *TransportCCExtension) Unmarshal(rawData []byte) error {
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if len(rawData) < transportCCExtensionSize {
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return errTooSmall
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}
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t.TransportSequence = binary.BigEndian.Uint16(rawData[0:2])
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return nil
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}
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