Files
donut/internal/controllers/h264_controller.go
2024-01-31 14:23:20 -03:00

60 lines
1.2 KiB
Go

package controllers
import (
"bytes"
"fmt"
"github.com/flavioribeiro/donut/internal/entities"
)
func ParseNALUs(data []byte) (entities.NALUs, error) {
var nalus entities.NALUs
rawNALUs := bytes.Split(data, []byte{0x00, 0x00, 0x01})
for _, rawNALU := range rawNALUs[1:] {
nal, err := ParseNAL(rawNALU)
if err != nil {
return entities.NALUs{}, err
}
nalus.Units = append(nalus.Units, nal)
}
return nalus, nil
}
func ParseNAL(data []byte) (entities.NAL, error) {
index := 0
n := entities.NAL{}
if data[index]>>7&0x01 != 0 {
return entities.NAL{}, fmt.Errorf("forbidden_zero_bit is not 0")
}
n.RefIDC = (data[index] >> 5) & 0x03
n.UnitType = entities.NALUnitType(data[index] & 0x1f)
numBytesInRBSP := 0
nalUnitHeaderBytes := 1
n.HeaderBytes = data[:nalUnitHeaderBytes]
index += nalUnitHeaderBytes
n.RBSPByte = make([]byte, 0, 16)
i := 0
for i = index; i < len(data); i++ {
if (i+2) < len(data) && (data[i] == 0x00 && data[i+1] == 0x00 && data[i+2] == 0x03) {
n.RBSPByte = append(n.RBSPByte, data[i], data[i+1])
i += 2
numBytesInRBSP += 2
// 0x03
} else {
n.RBSPByte = append(n.RBSPByte, data[i])
numBytesInRBSP++
}
}
index += numBytesInRBSP
n.ParseRBSP()
return n, nil
}