56 lines
933 B
Go
56 lines
933 B
Go
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package h264
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import (
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"encoding/binary"
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"fmt"
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)
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// DecodeAVCC encodes NALUs from the AVCC code stream format.
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func DecodeAVCC(byts []byte) ([][]byte, error) {
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var ret [][]byte
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for len(byts) > 0 {
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if len(byts) < 4 {
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return nil, fmt.Errorf("invalid length")
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}
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le := binary.BigEndian.Uint32(byts)
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byts = byts[4:]
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if len(byts) < int(le) {
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return nil, fmt.Errorf("invalid length")
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}
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ret = append(ret, byts[:le])
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byts = byts[le:]
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}
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if len(ret) == 0 {
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return nil, fmt.Errorf("no NALUs decoded")
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}
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return ret, nil
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}
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// EncodeAVCC encodes NALUs into the AVCC code stream format.
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func EncodeAVCC(nalus [][]byte) ([]byte, error) {
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le := 0
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for _, nalu := range nalus {
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le += 4 + len(nalu)
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}
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ret := make([]byte, le)
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pos := 0
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for _, nalu := range nalus {
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ln := len(nalu)
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binary.BigEndian.PutUint32(ret[pos:], uint32(ln))
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pos += 4
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copy(ret[pos:], nalu)
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pos += ln
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}
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return ret, nil
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}
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