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joy4/codec/aacparser/parser.go

312 lines
11 KiB
Go

package aacparser
import (
"bytes"
"fmt"
"io"
"time"
"git.icomsys.co.kr/ljhwan026/joy4/av"
"git.icomsys.co.kr/ljhwan026/joy4/utils/bits"
)
// copied from libavcodec/mpeg4audio.h
const (
AOT_AAC_MAIN = 1 + iota ///< Y Main
AOT_AAC_LC ///< Y Low Complexity
AOT_AAC_SSR ///< N (code in SoC repo) Scalable Sample Rate
AOT_AAC_LTP ///< Y Long Term Prediction
AOT_SBR ///< Y Spectral Band Replication
AOT_AAC_SCALABLE ///< N Scalable
AOT_TWINVQ ///< N Twin Vector Quantizer
AOT_CELP ///< N Code Excited Linear Prediction
AOT_HVXC ///< N Harmonic Vector eXcitation Coding
AOT_TTSI = 12 + iota ///< N Text-To-Speech Interface
AOT_MAINSYNTH ///< N Main Synthesis
AOT_WAVESYNTH ///< N Wavetable Synthesis
AOT_MIDI ///< N General MIDI
AOT_SAFX ///< N Algorithmic Synthesis and Audio Effects
AOT_ER_AAC_LC ///< N Error Resilient Low Complexity
AOT_ER_AAC_LTP = 19 + iota ///< N Error Resilient Long Term Prediction
AOT_ER_AAC_SCALABLE ///< N Error Resilient Scalable
AOT_ER_TWINVQ ///< N Error Resilient Twin Vector Quantizer
AOT_ER_BSAC ///< N Error Resilient Bit-Sliced Arithmetic Coding
AOT_ER_AAC_LD ///< N Error Resilient Low Delay
AOT_ER_CELP ///< N Error Resilient Code Excited Linear Prediction
AOT_ER_HVXC ///< N Error Resilient Harmonic Vector eXcitation Coding
AOT_ER_HILN ///< N Error Resilient Harmonic and Individual Lines plus Noise
AOT_ER_PARAM ///< N Error Resilient Parametric
AOT_SSC ///< N SinuSoidal Coding
AOT_PS ///< N Parametric Stereo
AOT_SURROUND ///< N MPEG Surround
AOT_ESCAPE ///< Y Escape Value
AOT_L1 ///< Y Layer 1
AOT_L2 ///< Y Layer 2
AOT_L3 ///< Y Layer 3
AOT_DST ///< N Direct Stream Transfer
AOT_ALS ///< Y Audio LosslesS
AOT_SLS ///< N Scalable LosslesS
AOT_SLS_NON_CORE ///< N Scalable LosslesS (non core)
AOT_ER_AAC_ELD ///< N Error Resilient Enhanced Low Delay
AOT_SMR_SIMPLE ///< N Symbolic Music Representation Simple
AOT_SMR_MAIN ///< N Symbolic Music Representation Main
AOT_USAC_NOSBR ///< N Unified Speech and Audio Coding (no SBR)
AOT_SAOC ///< N Spatial Audio Object Coding
AOT_LD_SURROUND ///< N Low Delay MPEG Surround
AOT_USAC ///< N Unified Speech and Audio Coding
)
type MPEG4AudioConfig struct {
SampleRate int
ChannelLayout av.ChannelLayout
ObjectType uint
SampleRateIndex uint
ChannelConfig uint
}
var sampleRateTable = []int{
96000, 88200, 64000, 48000, 44100, 32000,
24000, 22050, 16000, 12000, 11025, 8000, 7350,
}
/*
These are the channel configurations:
0: Defined in AOT Specifc Config
1: 1 channel: front-center
2: 2 channels: front-left, front-right
3: 3 channels: front-center, front-left, front-right
4: 4 channels: front-center, front-left, front-right, back-center
5: 5 channels: front-center, front-left, front-right, back-left, back-right
6: 6 channels: front-center, front-left, front-right, back-left, back-right, LFE-channel
7: 8 channels: front-center, front-left, front-right, side-left, side-right, back-left, back-right, LFE-channel
8-15: Reserved
*/
var chanConfigTable = []av.ChannelLayout{
0,
av.CH_FRONT_CENTER,
av.CH_FRONT_LEFT | av.CH_FRONT_RIGHT,
av.CH_FRONT_CENTER | av.CH_FRONT_LEFT | av.CH_FRONT_RIGHT,
av.CH_FRONT_CENTER | av.CH_FRONT_LEFT | av.CH_FRONT_RIGHT | av.CH_BACK_CENTER,
av.CH_FRONT_CENTER | av.CH_FRONT_LEFT | av.CH_FRONT_RIGHT | av.CH_BACK_LEFT | av.CH_BACK_RIGHT,
av.CH_FRONT_CENTER | av.CH_FRONT_LEFT | av.CH_FRONT_RIGHT | av.CH_BACK_LEFT | av.CH_BACK_RIGHT | av.CH_LOW_FREQ,
av.CH_FRONT_CENTER | av.CH_FRONT_LEFT | av.CH_FRONT_RIGHT | av.CH_SIDE_LEFT | av.CH_SIDE_RIGHT | av.CH_BACK_LEFT | av.CH_BACK_RIGHT | av.CH_LOW_FREQ,
}
func ParseADTSHeader(frame []byte) (config MPEG4AudioConfig, hdrlen int, framelen int, samples int, err error) {
if frame[0] != 0xff || frame[1]&0xf6 != 0xf0 {
err = fmt.Errorf("aacparser: not adts header")
return
}
config.ObjectType = uint(frame[2]>>6) + 1
config.SampleRateIndex = uint(frame[2] >> 2 & 0xf)
config.ChannelConfig = uint(frame[2]<<2&0x4 | frame[3]>>6&0x3)
if config.ChannelConfig == uint(0) {
err = fmt.Errorf("aacparser: adts channel count invalid")
return
}
(&config).Complete()
framelen = int(frame[3]&0x3)<<11 | int(frame[4])<<3 | int(frame[5]>>5)
samples = (int(frame[6]&0x3) + 1) * 1024
hdrlen = 7
if frame[1]&0x1 == 0 {
hdrlen = 9
}
if framelen < hdrlen {
err = fmt.Errorf("aacparser: adts framelen < hdrlen")
return
}
return
}
const ADTSHeaderLength = 7
func FillADTSHeader(header []byte, config MPEG4AudioConfig, samples int, payloadLength int) {
payloadLength += 7
//AAAAAAAA AAAABCCD EEFFFFGH HHIJKLMM MMMMMMMM MMMOOOOO OOOOOOPP (QQQQQQQQ QQQQQQQQ)
header[0] = 0xff
header[1] = 0xf1
header[2] = 0x50
header[3] = 0x80
header[4] = 0x43
header[5] = 0xff
header[6] = 0xcd
//config.ObjectType = uint(frames[2]>>6)+1
//config.SampleRateIndex = uint(frames[2]>>2&0xf)
//config.ChannelConfig = uint(frames[2]<<2&0x4|frames[3]>>6&0x3)
header[2] = (byte(config.ObjectType-1)&0x3)<<6 | (byte(config.SampleRateIndex)&0xf)<<2 | byte(config.ChannelConfig>>2)&0x1
header[3] = header[3]&0x3f | byte(config.ChannelConfig&0x3)<<6
header[3] = header[3]&0xfc | byte(payloadLength>>11)&0x3
header[4] = byte(payloadLength >> 3)
header[5] = header[5]&0x1f | (byte(payloadLength)&0x7)<<5
header[6] = header[6]&0xfc | byte(samples/1024-1)
return
}
func readObjectType(r *bits.Reader) (objectType uint, err error) {
if objectType, err = r.ReadBits(5); err != nil {
return
}
if objectType == AOT_ESCAPE {
var i uint
if i, err = r.ReadBits(6); err != nil {
return
}
objectType = 32 + i
}
return
}
func writeObjectType(w *bits.Writer, objectType uint) (err error) {
if objectType >= 32 {
if err = w.WriteBits(AOT_ESCAPE, 5); err != nil {
return
}
if err = w.WriteBits(objectType-32, 6); err != nil {
return
}
} else {
if err = w.WriteBits(objectType, 5); err != nil {
return
}
}
return
}
func readSampleRateIndex(r *bits.Reader) (index uint, err error) {
if index, err = r.ReadBits(4); err != nil {
return
}
if index == 0xf {
if index, err = r.ReadBits(24); err != nil {
return
}
}
return
}
func writeSampleRateIndex(w *bits.Writer, index uint) (err error) {
if index >= 0xf {
if err = w.WriteBits(0xf, 4); err != nil {
return
}
if err = w.WriteBits(index, 24); err != nil {
return
}
} else {
if err = w.WriteBits(index, 4); err != nil {
return
}
}
return
}
func (self MPEG4AudioConfig) IsValid() bool {
return self.ObjectType > 0
}
func (self *MPEG4AudioConfig) Complete() {
if int(self.SampleRateIndex) < len(sampleRateTable) {
self.SampleRate = sampleRateTable[self.SampleRateIndex]
}
if int(self.ChannelConfig) < len(chanConfigTable) {
self.ChannelLayout = chanConfigTable[self.ChannelConfig]
}
return
}
func ParseMPEG4AudioConfigBytes(data []byte) (config MPEG4AudioConfig, err error) {
// copied from libavcodec/mpeg4audio.c avpriv_mpeg4audio_get_config()
r := bytes.NewReader(data)
br := &bits.Reader{R: r}
if config.ObjectType, err = readObjectType(br); err != nil {
return
}
if config.SampleRateIndex, err = readSampleRateIndex(br); err != nil {
return
}
if config.ChannelConfig, err = br.ReadBits(4); err != nil {
return
}
(&config).Complete()
return
}
func WriteMPEG4AudioConfig(w io.Writer, config MPEG4AudioConfig) (err error) {
bw := &bits.Writer{W: w}
if err = writeObjectType(bw, config.ObjectType); err != nil {
return
}
if config.SampleRateIndex == 0 {
for i, rate := range sampleRateTable {
if rate == config.SampleRate {
config.SampleRateIndex = uint(i)
}
}
}
if err = writeSampleRateIndex(bw, config.SampleRateIndex); err != nil {
return
}
if config.ChannelConfig == 0 {
for i, layout := range chanConfigTable {
if layout == config.ChannelLayout {
config.ChannelConfig = uint(i)
}
}
}
if err = bw.WriteBits(config.ChannelConfig, 4); err != nil {
return
}
if err = bw.FlushBits(); err != nil {
return
}
return
}
type CodecData struct {
ConfigBytes []byte
Config MPEG4AudioConfig
}
func (self CodecData) Type() av.CodecType {
return av.AAC
}
func (self CodecData) MPEG4AudioConfigBytes() []byte {
return self.ConfigBytes
}
func (self CodecData) ChannelLayout() av.ChannelLayout {
return self.Config.ChannelLayout
}
func (self CodecData) SampleRate() int {
return self.Config.SampleRate
}
func (self CodecData) SampleFormat() av.SampleFormat {
return av.FLTP
}
func (self CodecData) PacketDuration(data []byte) (dur time.Duration, err error) {
dur = time.Duration(1024) * time.Second / time.Duration(self.Config.SampleRate)
return
}
func NewCodecDataFromMPEG4AudioConfig(config MPEG4AudioConfig) (self CodecData, err error) {
b := &bytes.Buffer{}
WriteMPEG4AudioConfig(b, config)
return NewCodecDataFromMPEG4AudioConfigBytes(b.Bytes())
}
func NewCodecDataFromMPEG4AudioConfigBytes(config []byte) (self CodecData, err error) {
self.ConfigBytes = config
if self.Config, err = ParseMPEG4AudioConfigBytes(config); err != nil {
err = fmt.Errorf("aacparser: parse MPEG4AudioConfig failed(%s)", err)
return
}
return
}