fix wav2flac encoding

cmd/wav2flac/main.go

@@ -88,7 +88,7 @@ func wav2flac(wavPath string, force bool) error {
 		return errors.WithStack(err)
 	}
 	// Number of samples per channel and block.
-	const nsamplesPerChannel = 16
+	const nsamplesPerChannel = 4096
 	nsamplesPerBlock := nchannels * nsamplesPerChannel
 	buf := &audio.IntBuffer{
 		Format: &audio.Format{
@@ -116,6 +116,10 @@ func wav2flac(wavPath string, force bool) error {
 		if n == 0 {
 			break
 		}
+		if n < 16*nchannels {
+			n = 16
+			//break
+		}
 		for _, subframe := range subframes {
 			subHdr := frame.SubHeader{
 				// Specifies the prediction method used to encode the audio sample of the
@@ -130,7 +134,7 @@ func wav2flac(wavPath string, force bool) error {
 			subframe.NSamples = n / nchannels
 			subframe.Samples = subframe.Samples[:subframe.NSamples]
 		}
-		for i, sample := range buf.Data {
+		for i, sample := range buf.Data[:n] {
 			subframe := subframes[i%nchannels]
 			subframe.Samples[i/nchannels] = int32(sample)
 		}
@@ -160,7 +164,7 @@ func wav2flac(wavPath string, force bool) error {
 			HasFixedBlockSize: false,
 			// Block size in inter-channel samples, i.e. the number of audio samples
 			// in each subframe.
-			BlockSize: uint16(nsamplesPerChannel),
+			BlockSize: uint16(subframes[0].NSamples),
 			// Sample rate in Hz; a 0 value implies unknown, get sample rate from
 			// StreamInfo.
 			SampleRate: uint32(sampleRate),

go.mod

@@ -1,6 +1,6 @@
 module git.gammaspectra.live/S.O.N.G/flacgo
 
-go 1.14
+go 1.18
 
 require (
 	github.com/go-audio/audio v1.0.0
@@ -9,3 +9,5 @@ require (
 	github.com/mewkiz/pkg v0.0.0-20211102230744-16a6ce8f1b77
 	github.com/pkg/errors v0.9.1
 )
+
+require github.com/go-audio/riff v1.0.0 // indirect