Intégration de libsoxr pour le rééchantillonnage audio

pmostream/conversion.go

@@ -0,0 +1,88 @@
+package pmostream
+
+import (
+	"encoding/binary"
+	"math"
+)
+
+func ConvertFloat64ToFloat32(samples [][2]float64) []float32 {
+	if len(samples) == 0 {
+		return nil
+	}
+	result := make([]float32, len(samples)*2)
+	for i, s := range samples {
+		result[2*i] = float32(clamp(s[0], -1.0, 1.0))
+		result[2*i+1] = float32(clamp(s[1], -1.0, 1.0))
+	}
+	return result
+}
+
+func ConvertFloat64ToPCM(samples [][2]float64) []byte {
+	if len(samples) == 0 {
+		return nil
+	}
+	buf := make([]byte, len(samples)*4)
+	for i, s := range samples {
+		l := int16(clamp(s[0], -1.0, 1.0) * 32767.0)
+		r := int16(clamp(s[1], -1.0, 1.0) * 32767.0)
+		binary.LittleEndian.PutUint16(buf[4*i:], uint16(uint16(l)))
+		binary.LittleEndian.PutUint16(buf[4*i+2:], uint16(uint16(r)))
+	}
+	return buf
+}
+
+func Float32ToPCM(samples []float32) []byte {
+	if len(samples) == 0 {
+		return nil
+	}
+	buf := make([]byte, len(samples)*2)
+	for i, v := range samples {
+		val := int16(clamp(float64(v), -1.0, 1.0) * 32767.0)
+		binary.LittleEndian.PutUint16(buf[2*i:], uint16(val))
+	}
+	return buf
+}
+
+func Float32ToBytes(samples []float32) []byte {
+	if len(samples) == 0 {
+		return nil
+	}
+	buf := make([]byte, len(samples)*4)
+	for i, v := range samples {
+		binary.LittleEndian.PutUint32(buf[i*4:], math.Float32bits(v))
+	}
+	return buf
+}
+
+func BytesToFloat32(data []byte) []float32 {
+	if len(data)%4 != 0 {
+		return nil
+	}
+	result := make([]float32, len(data)/4)
+	for i := range result {
+		result[i] = math.Float32frombits(binary.LittleEndian.Uint32(data[i*4:]))
+	}
+	return result
+}
+
+func PcmToFloat32(data []byte) []float32 {
+	if len(data)%2 != 0 {
+		return nil
+	}
+	result := make([]float32, len(data)/2)
+	for i := 0; i < len(result); i++ {
+		val := int16(binary.LittleEndian.Uint16(data[2*i:]))
+		result[i] = float32(val) / 32768.0
+	}
+	return result
+}
+
+func clamp(val, min, max float64) float64 {
+	if val < min {
+		return min
+	}
+	if val > max {
+		return max
+	}
+	return val
+}