mirror of https://bitbucket.org/ausocean/av.git
27 lines
679 B
Go
27 lines
679 B
Go
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package rtcp
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import (
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"encoding/binary"
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"errors"
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)
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// Timestamp gets the timestamp from a receiver report and returns as the most
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// significant word, and the least significant word. If the given bytes do not
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// represent a valid receiver report, and error is returned.
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func Timestamp(buf []byte) (msw, lsw uint32, err error) {
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// First check version of rtcp
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if (buf[0] & 0xc0 >> 6) != 2 {
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return 0, 0, errors.New("incompatible RTCP version")
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}
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// Check type of packet
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if buf[1] != typeSenderReport {
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return 0, 0, errors.New("rtcp packet is not of sender report type")
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}
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msw = binary.BigEndian.Uint32(buf[8:])
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lsw = binary.BigEndian.Uint32(buf[12:])
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return
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}
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