117 lines
2.1 KiB
Go
117 lines
2.1 KiB
Go
// Package aac provides AAC codec encoder based on [VisualOn AAC encoder library](https://github.com/mstorsjo/vo-aacenc) library.
|
|
package aac
|
|
|
|
import "C"
|
|
|
|
import (
|
|
"io"
|
|
"unsafe"
|
|
|
|
"github.com/gen2brain/aac-go/aacenc"
|
|
)
|
|
|
|
// Options represent encoding options.
|
|
type Options struct {
|
|
// Audio file sample rate
|
|
SampleRate int
|
|
// Encoder bit rate in bits/sec
|
|
BitRate int
|
|
// Number of channels on input (1,2)
|
|
NumChannels int
|
|
}
|
|
|
|
// Encoder type.
|
|
type Encoder struct {
|
|
w io.Writer
|
|
|
|
insize int
|
|
inbuf []byte
|
|
outbuf []byte
|
|
}
|
|
|
|
// NewEncoder returns new AAC encoder.
|
|
func NewEncoder(w io.Writer, opts *Options) (e *Encoder, err error) {
|
|
e = &Encoder{}
|
|
e.w = w
|
|
|
|
if opts.BitRate == 0 {
|
|
opts.BitRate = 64000
|
|
}
|
|
|
|
ret := aacenc.Init(aacenc.VoAudioCodingAac)
|
|
err = aacenc.ErrorFromResult(ret)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
var params aacenc.AacencParam
|
|
params.SampleRate = int32(opts.SampleRate)
|
|
params.BitRate = int32(opts.BitRate)
|
|
params.NChannels = int16(opts.NumChannels)
|
|
params.AdtsUsed = 1
|
|
|
|
ret = aacenc.SetParam(aacenc.VoPidAacEncparam, unsafe.Pointer(¶ms))
|
|
err = aacenc.ErrorFromResult(ret)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
e.insize = int(opts.NumChannels) * 2 * 1024
|
|
|
|
e.inbuf = make([]byte, e.insize)
|
|
e.outbuf = make([]byte, 20480)
|
|
|
|
return
|
|
}
|
|
|
|
// Encode encodes data from reader.
|
|
func (e *Encoder) Encode(r io.Reader) (err error) {
|
|
for {
|
|
n, err := r.Read(e.inbuf)
|
|
if err != nil {
|
|
if err != io.EOF {
|
|
return err
|
|
}
|
|
break
|
|
}
|
|
|
|
if n < e.insize {
|
|
break
|
|
}
|
|
|
|
var outinfo aacenc.VoAudioOutputinfo
|
|
var input, output aacenc.VoCodecBuffer
|
|
|
|
input.Buffer = C.CBytes(e.inbuf)
|
|
input.Length = uint64(n)
|
|
|
|
ret := aacenc.SetInputData(&input)
|
|
err = aacenc.ErrorFromResult(ret)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
output.Buffer = C.CBytes(e.outbuf)
|
|
output.Length = uint64(len(e.outbuf))
|
|
|
|
ret = aacenc.GetOutputData(&output, &outinfo)
|
|
err = aacenc.ErrorFromResult(ret)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
_, err = e.w.Write(C.GoBytes(output.Buffer, C.int(output.Length)))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Close closes encoder.
|
|
func (e *Encoder) Close() error {
|
|
ret := aacenc.Uninit()
|
|
return aacenc.ErrorFromResult(ret)
|
|
}
|