Beispiel #1
0
		private double[] MagnitudeSpectrum(float[] frame)
		{
			// prepare the input arrays
			FFTW.DoubleArray fftwInput = new FFTW.DoubleArray(MathUtils.FloatToDouble(frame));
			
			int complexSize = (frame.Length >> 1) + 1;
			FFTW.ComplexArray fftwOutput = new FFTW.ComplexArray(complexSize);
			
			FFTW.ForwardTransform(fftwInput, fftwOutput);
			double[] magSpectrum = fftwOutput.Abs;
			
			/*
			double[] magSpectrum = new double[frame.Length];

			// calculate FFT for current frame
			fft.ComputeFFT(frame);
			
			// System.err.println("FFT SUCCEED");
			// calculate magnitude spectrum
			for (int k = 0; k < frame.Length; k++)
			{
				magSpectrum[k] = Math.Sqrt(fft.real[k] * fft.real[k] + fft.imag[k] * fft.imag[k]);
			}
			 */
			return magSpectrum;
		}
Beispiel #2
0
        public static void ForwardTransform(FFTW.DoubleArray input, FFTW.ComplexArray output)
        {
            IntPtr plan = FFTW.dft_r2c_1d(input.Length, input.Handle, output.Handle, Flags.Estimate);

            //FFTW.print_plan(plan);
            FFTW.execute(plan);
            FFTW.destroy_plan(plan);
        }
Beispiel #3
0
        public static void BackwardTransform(FFTW.ComplexArray input, FFTW.DoubleArray output)
        {
            // TODO: make sure to use input.Length and not the output.Length ?!
            IntPtr plan = FFTW.dft_c2r_1d(input.Length, input.Handle, output.Handle, Flags.Estimate);

            //FFTW.print_plan(plan);
            FFTW.execute(plan);
            FFTW.destroy_plan(plan);
        }
Beispiel #4
0
        private static double GetComponentWeightCenter(List<double[]> a, int size, int component)
        {
            double[] windowedValues = a.GetWindowedDimension(component, size, HannWindow);

            FFTW.DoubleArray fftwInput = new FFTW.DoubleArray(windowedValues);
            FFTW.ComplexArray fftwOutput = new FFTW.ComplexArray((size >> 1) + 1);

            FFTW.ForwardTransform(fftwInput, fftwOutput);

            return fftwOutput.Values.GetWeightCenter();
        }
        private static double GetComponentWeightCenter(List <double[]> a, int size, int component)
        {
            double[] windowedValues = a.GetWindowedDimension(component, size, HannWindow);

            FFTW.DoubleArray  fftwInput  = new FFTW.DoubleArray(windowedValues);
            FFTW.ComplexArray fftwOutput = new FFTW.ComplexArray((size >> 1) + 1);

            FFTW.ForwardTransform(fftwInput, fftwOutput);

            return(fftwOutput.Values.GetWeightCenter());
        }
Beispiel #6
0
        public static void FFTWTestUsingDouble(string CSVFilePath=null, double[] audio_data=null, int testLoopCount=1)
        {
            if (audio_data == null) {
                audio_data = GetSignalTestData();
            }

            // prepare the input arrays
            FFTW.DoubleArray fftwInput = new FFTW.DoubleArray(audio_data);

            int complexSize = (audio_data.Length >> 1) + 1;
            FFTW.ComplexArray fftwOutput = new FFTW.ComplexArray(complexSize);

            // loop if neccesary - e.g. for performance test purposes
            for (int i = 0; i < testLoopCount; i++) {
                // perform the FFT
                FFTW.ForwardTransform(fftwInput, fftwOutput);
            }

            // get the result
            double[] spectrum_fft_real = fftwOutput.Real;
            double[] spectrum_fft_imag = fftwOutput.Imag;
            double[] spectrum_fft_abs = fftwOutput.Abs;

            // prepare the input arrays
            FFTW.ComplexArray fftwBackwardInput = new FFTW.ComplexArray(spectrum_fft_real, spectrum_fft_imag);
            FFTW.DoubleArray fftwBackwardOutput = new FFTW.DoubleArray(audio_data.Length);

            // perform the inverse FFT (IFFT)
            FFTW.BackwardTransform(fftwBackwardInput, fftwBackwardOutput);

            // get the result
            double[] spectrum_inverse_real = fftwBackwardOutput.ValuesDivedByN;

            // pad for output
            if (spectrum_fft_real.Length != audio_data.Length) Array.Resize(ref spectrum_fft_real, audio_data.Length);
            if (spectrum_fft_imag.Length != audio_data.Length) Array.Resize(ref spectrum_fft_imag, audio_data.Length);
            if (spectrum_fft_abs.Length != audio_data.Length) Array.Resize(ref spectrum_fft_abs, audio_data.Length);

            if (CSVFilePath!=null) {
                CommonUtils.Export.exportCSV(CSVFilePath, audio_data, spectrum_fft_real, spectrum_fft_imag, spectrum_fft_abs, spectrum_inverse_real);
            }
        }