86 lines
1.6 KiB
Go
86 lines
1.6 KiB
Go
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package audiodriver
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import (
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"bytes"
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"encoding/binary"
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"errors"
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"io"
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)
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// Skip riff header and `fmt ` just 16 bytes
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const (
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FmtHeaderOffset int64 = 0x0c
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FmtHeaderIDSize int64 = 4
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FmtHeaderChunkSizeSize int64 = 4
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)
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type WavHeader struct {
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ID [4]byte
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Size uint32
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AudioFormat uint16
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NumChannels uint16
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SampleRate uint32
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ByteRate uint32
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BlockAlign uint16
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BitsPerSample uint16
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}
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func (w *WavHeader) Parse(f io.ReadSeeker) error {
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if _, err := f.Seek(FmtHeaderOffset, io.SeekStart); err != nil {
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return err
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}
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var id [4]byte
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if _, err := f.Read(id[:]); err != nil {
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return err
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}
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if bytes.Equal(id[:], []byte{'f', 'm', 't', '0'}[:]) {
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return errors.New("bad header")
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}
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w.ID = id
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var size [4]byte
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if _, err := f.Read(size[:]); err != nil {
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return err
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}
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w.Size = binary.LittleEndian.Uint32(size[:])
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var af [2]byte
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if _, err := f.Read(af[:]); err != nil {
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return err
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}
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w.AudioFormat = binary.LittleEndian.Uint16(af[:])
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var nc [2]byte
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if _, err := f.Read(nc[:]); err != nil {
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return err
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}
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w.NumChannels = binary.LittleEndian.Uint16(nc[:])
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var sr [4]byte
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if _, err := f.Read(sr[:]); err != nil {
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return err
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}
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w.SampleRate = binary.LittleEndian.Uint32(sr[:])
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var br [4]byte
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if _, err := f.Read(br[:]); err != nil {
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return err
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}
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w.ByteRate = binary.LittleEndian.Uint32(br[:])
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var ba [2]byte
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if _, err := f.Read(ba[:]); err != nil {
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return err
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}
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w.BlockAlign = binary.LittleEndian.Uint16(ba[:])
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var bps [2]byte
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if _, err := f.Read(ba[:]); err != nil {
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return err
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}
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w.BitsPerSample = binary.LittleEndian.Uint16(bps[:])
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return nil
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}
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