private void Recognize(ref string result, int sampleRate)
        {
            amplitudeSum = 0.0f;
            for (int i = 0; i < playingAudioSpectrum.Length; ++i)
            {
                amplitudeSum += playingAudioSpectrum[i];
            }
            if (amplitudeSum >= amplitudeThreshold)
            {
                MathToolBox.Convolute(playingAudioSpectrum, gaussianFilter, MathToolBox.EPaddleType.Repeat, smoothedAudioSpectrum);
                MathToolBox.FindLocalLargestPeaks(smoothedAudioSpectrum, peakValues, peakPositions);
                frequencyUnit = sampleRate / windowSize;
                for (int i = 0; i < formantArray.Length; ++i)
                {
                    formantArray[i] = peakPositions[i] * frequencyUnit;
                }

                for (int i = 0; i < currentVowelFormantCeilValues.Length; ++i)
                {
                    if (formantArray[0] > currentVowelFormantCeilValues[i])
                    {
                        result = currentVowels[i];
                    }
                }
            }
        }
        public string[] RecognizeAllByAudioClip(AudioClip audioClip)
        {
            int recognizeSampleCount = Mathf.CeilToInt((float)(audioClip.samples) / (float)(shiftStepSize));

            string[] result               = new string[recognizeSampleCount];
            float[]  currentAudioData     = new float[this.windowSize];
            float[]  currentAudioSpectrum = new float[this.windowSize];

            for (int i = 0; i < recognizeSampleCount; ++i)
            {
                audioClip.GetData(currentAudioData, i * shiftStepSize);
                for (int j = 0; j < windowSize; ++j)
                {
                    currentAudioData[j] *= windowArray[j];
                }
                currentAudioSpectrum = MathToolBox.DiscreteCosineTransform(currentAudioData);

                amplitudeSum = 0.0f;
                for (int k = 0; k < windowSize; ++k)
                {
                    amplitudeSum += currentAudioSpectrum[k];
                }

                if (amplitudeSum >= amplitudeThreshold)
                {
                    MathToolBox.Convolute(currentAudioSpectrum, gaussianFilter, MathToolBox.EPaddleType.Repeat, smoothedAudioSpectrum);
                    MathToolBox.FindLocalLargestPeaks(smoothedAudioSpectrum, peakValues, peakPositions);
                    frequencyUnit = audioClip.frequency / 2 / windowSize;
                    for (int l = 0; l < formantArray.Length; ++l)
                    {
                        formantArray[l] = peakPositions[l] * frequencyUnit;
                    }

                    for (int m = 0; m < currentVowelFormantCeilValues.Length; ++m)
                    {
                        if (formantArray[0] > currentVowelFormantCeilValues[m])
                        {
                            result[i] = currentVowels[m];
                        }
                    }
                }
            }
            return(result);
        }