Files
engine/audio_track.go
2021-05-09 12:57:47 +08:00

83 lines
1.9 KiB
Go

package engine
import (
"github.com/Monibuca/utils/v3"
"github.com/Monibuca/utils/v3/codec"
"github.com/pion/rtp"
)
type AudioPack struct {
Timestamp uint32
Payload []byte
SequenceNumber uint16
}
type AudioTrack struct {
Track_Audio
SoundFormat byte //4bit
SoundRate int //2bit
SoundSize byte //1bit
Channels byte //1bit
RtmpTag []byte //rtmp协议需要先发这个帧
}
func (at *AudioPack) ToRTMPTag(aac byte) []byte {
audio := at.Payload
l := len(audio) + 1
isAAC := 0
if aac>>4 == 10 {
isAAC = 1
}
payload := utils.GetSlice(l + isAAC)
payload[0] = aac
if isAAC == 1 {
payload[1] = 1
copy(payload[2:], audio)
} else {
copy(payload[1:], audio)
}
return payload
}
// Push 来自发布者推送的音频
func (at *AudioTrack) Push(timestamp uint32, payload []byte) {
if at.Stream != nil {
at.Stream.Update()
}
payloadLen := len(payload)
if payloadLen < 4 {
return
}
audio := at.Buffer
audio.Current.Timestamp = timestamp
audio.Current.Payload = payload
at.Track_Audio.GetBPS(payloadLen)
audio.NextW()
}
func (at *AudioTrack) PushRTP(pack rtp.Packet) {
t := pack.Timestamp / 90
for _, payload := range codec.ParseRTPAAC(pack.Payload) {
at.Push(t, payload)
}
}
func NewAudioTrack() *AudioTrack {
var result AudioTrack
result.Buffer = NewRing_Audio()
return &result
}
func (at *AudioTrack) SetASC(asc []byte) {
at.RtmpTag = append([]byte{0xAF, 0}, asc...)
config1 := asc[0]
config2 := asc[1]
at.SoundFormat = 10
//audioObjectType = (config1 & 0xF8) >> 3
// 1 AAC MAIN ISO/IEC 14496-3 subpart 4
// 2 AAC LC ISO/IEC 14496-3 subpart 4
// 3 AAC SSR ISO/IEC 14496-3 subpart 4
// 4 AAC LTP ISO/IEC 14496-3 subpart 4
at.SoundRate = codec.SamplingFrequencies[((config1&0x7)<<1)|(config2>>7)]
at.Channels = (config2 >> 3) & 0x0F //声道
//frameLengthFlag = (config2 >> 2) & 0x01
//dependsOnCoreCoder = (config2 >> 1) & 0x01
//extensionFlag = config2 & 0x01
}