func LogAmp2MCep(logAmp []float64, order int, alpha float64) []float64 {
	ceps := LogAmplitude2Cepsturm(logAmp)
	ceps[0] /= 2.0
	return FrequencyWarping(ceps, order, alpha)
}
LogAmp2MCep returns mel-cepstrum from a given log amplitude spectrum.
Note: This function requires symmetric log-amplitude that length correspond
to the number of frequency bins in fourier analysis.
package mgcep
import (
	"github.com/mjibson/go-dsp/fft"
	"github.com/r9y9/gossp"
	"github.com/r9y9/gossp/3rdparty/mcepalpha"
	"github.com/r9y9/gossp/3rdparty/sptk"
)
func MGCep(audioBuffer []float64,
	order int, alpha, gamma float64) []float64 {
	return sptk.MGCepWithDefaultParameters(audioBuffer, order, alpha, gamma)
}
func CalcMCepAlpha(sampleRate int) float64 {
	return mcepalpha.CalcMcepAlpha(sampleRate)
}
func LogAmplitude2Cepsturm(logAmp []float64) []float64 {
	return gossp.ToReal(fft.IFFTReal(logAmp))
}
func Cepstrum2LogAmplitude(ceps []float64) []float64 {
	return gossp.ToReal(fft.FFTReal(ceps))
}