68 lines
1.4 KiB
Go
68 lines
1.4 KiB
Go
// Copyright © Go Opus Authors (see AUTHORS file)
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//
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// License for use of this code is detailed in the LICENSE file
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package opus
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import (
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"math"
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)
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// utility functions for unit tests
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func addSineFloat32(buf []float32, sampleRate int, freq float64) {
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factor := 2 * math.Pi * freq / float64(sampleRate)
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for i := range buf {
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buf[i] += float32(math.Sin(float64(i) * factor))
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}
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}
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func addSine(buf []int16, sampleRate int, freq float64) {
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factor := 2 * math.Pi * freq / float64(sampleRate)
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for i := range buf {
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buf[i] += int16(math.Sin(float64(i)*factor) * (math.MaxInt16 - 1))
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}
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}
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func maxDiff(a []int16, b []int16) int32 {
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if len(a) != len(b) {
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return math.MaxInt16
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}
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var max int32 = 0
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for i := range a {
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d := int32(a[i]) - int32(b[i])
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if d < 0 {
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d = -d
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}
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if d > max {
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max = d
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}
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}
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return max
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}
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func interleave(a []int16, b []int16) []int16 {
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if len(a) != len(b) {
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panic("interleave: buffers must have equal length")
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}
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result := make([]int16, 2*len(a))
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for i := range a {
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result[2*i] = a[i]
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result[2*i+1] = b[i]
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}
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return result
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}
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func split(interleaved []int16) ([]int16, []int16) {
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if len(interleaved)%2 != 0 {
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panic("split: interleaved buffer must have even number of samples")
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}
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left := make([]int16, len(interleaved)/2)
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right := make([]int16, len(interleaved)/2)
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for i := range left {
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left[i] = interleaved[2*i]
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right[i] = interleaved[2*i+1]
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}
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return left, right
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}
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