91 lines
1.3 KiB
Go
91 lines
1.3 KiB
Go
package h264
|
|
|
|
// AntiCompetitionAdd adds the anti-competition bytes to a NALU.
|
|
func AntiCompetitionAdd(nalu []byte) []byte {
|
|
var ret []byte
|
|
step := 0
|
|
start := 0
|
|
|
|
for i, b := range nalu {
|
|
switch step {
|
|
case 0:
|
|
if b == 0 {
|
|
step++
|
|
}
|
|
|
|
case 1:
|
|
if b == 0 {
|
|
step++
|
|
} else {
|
|
step = 0
|
|
}
|
|
|
|
case 2:
|
|
switch b {
|
|
case 3, 2, 1, 0:
|
|
ret = append(ret, nalu[start:i-2]...)
|
|
ret = append(ret, []byte{0x00, 0x00, 0x03, b}...)
|
|
step = 0
|
|
start = i + 1
|
|
|
|
default:
|
|
step = 0
|
|
}
|
|
}
|
|
}
|
|
|
|
ret = append(ret, nalu[start:]...)
|
|
return ret
|
|
}
|
|
|
|
// AntiCompetitionRemove removes the anti-competition bytes from a NALU.
|
|
func AntiCompetitionRemove(nalu []byte) []byte {
|
|
// 0x00 0x00 0x03 0x00 -> 0x00 0x00 0x00
|
|
// 0x00 0x00 0x03 0x01 -> 0x00 0x00 0x01
|
|
// 0x00 0x00 0x03 0x02 -> 0x00 0x00 0x02
|
|
// 0x00 0x00 0x03 0x03 -> 0x00 0x00 0x03
|
|
|
|
var ret []byte
|
|
step := 0
|
|
start := 0
|
|
|
|
for i, b := range nalu {
|
|
switch step {
|
|
case 0:
|
|
if b == 0 {
|
|
step++
|
|
}
|
|
|
|
case 1:
|
|
if b == 0 {
|
|
step++
|
|
} else {
|
|
step = 0
|
|
}
|
|
|
|
case 2:
|
|
if b == 3 {
|
|
step++
|
|
} else {
|
|
step = 0
|
|
}
|
|
|
|
case 3:
|
|
switch b {
|
|
case 3, 2, 1, 0:
|
|
ret = append(ret, nalu[start:i-3]...)
|
|
ret = append(ret, []byte{0x00, 0x00, b}...)
|
|
step = 0
|
|
start = i + 1
|
|
|
|
default:
|
|
step = 0
|
|
}
|
|
}
|
|
}
|
|
|
|
ret = append(ret, nalu[start:]...)
|
|
|
|
return ret
|
|
}
|