Example #1
0
        private void ProcessSample(float sample)
        {
            var windowsize = size;

            _recorded.Add(sample);
            if (_recorded.Count == windowsize)
            {
                #region add

                double[]    dftIn     = new double[size];
                double[]    dftInIm   = new double[size];
                DataPoint[] DftIn     = new DataPoint[size];
                DataPoint[] DFTResult = new DataPoint[size];
                DataPoint[] FFTResult = new DataPoint[size];
                double[]    data      = new double[size];
                for (int i = 0; i < size; i++)
                {
                    dftInIm[i] = 0.0;
                }
                var window = MathNet.Numerics.Window.Hamming(windowsize);
                _recorded = _recorded.Select((v, i) => (double)v * window[i]).ToList();
                dftIn     = _recorded.Take(size).ToArray();


                // FFT
                FFT(dftIn, dftInIm, out reFFT, out imFFT, (int)Math.Log(size, 2));
                // 波形显示
                for (int i = 0; i < size / 2; i++)
                {
                    if (i > 0)
                    {
                        float  a = ((float)fs / size);
                        float  x = (float)i * a;
                        double y = Math.Sqrt(reFFT[i] * reFFT[i] + imFFT[i] * imFFT[i]);
                        FFTResult[i] = new DataPoint(x, y);
                    }
                }

                line1.ItemsSource = FFTResult.Take((FFTResult.Count() / 20));
                #endregion
                _recorded.Clear();
            }
        }
Example #2
0
        private void ProcessSample(float sample)
        {
            var windowsize = size;

            _recorded.Add(sample);
            if (_recorded.Count == windowsize)
            {
                #region add
                // DFT用データ
                double[]    dftIn     = new double[size];
                double[]    dftInIm   = new double[size];
                DataPoint[] DftIn     = new DataPoint[size];
                DataPoint[] DFTResult = new DataPoint[size];
                DataPoint[] FFTResult = new DataPoint[size];
                // 窓関数後データ
                double[] data = new double[size];
                // 波形生成
                for (int i = 0; i < size; i++)
                {
                    dftInIm[i] = 0.0;
                }
                var window = MathNet.Numerics.Window.Hamming(windowsize);
                _recorded = _recorded.Select((v, i) => (double)v * window[i]).ToList();
                dftIn     = _recorded.Take(size).ToArray();


                // DFT
                //DFT(size, dftIn, out re, out im);
                // FFT
                FFT(dftIn, dftInIm, out reFFT, out imFFT, (int)Math.Log(size, 2));
                // DFT波形表示
                for (int i = 0; i < size / 2; i++)
                {
                    if (i > 0)
                    {
                        //FFTの横軸の周波数の単位、分解能についてはここを見る
                        //URL http://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q1350561093
                        //FFTの分解能(ひと間隔)はfs/sizeでももとまる。また、横軸の最大値は、サンプリング周波数の半分(サンプリング定理)となる。

                        //DFTResult[i] = new DataPoint((double)i, Math.Sqrt(re[i] * re[i] + im[i] * im[i]));
                        float  a = ((float)fs / size);
                        float  x = (float)i * a;
                        double y = Math.Sqrt(reFFT[i] * reFFT[i] + imFFT[i] * imFFT[i]);
                        FFTResult[i] = new DataPoint(x, y);
                    }
                }

                //line1.ItemsSource = dftIn;
                line2.ItemsSource = FFTResult.Take((FFTResult.Count() / 20));


                //line1.ItemsSource = DFTResult;
                #endregion


                //var points = _recorded.Select((v, index) =>
                //        new DataPoint((double)index, v)
                //    ).ToList();

                //var window = MathNet.Numerics.Window.Hamming(windowsize);
                //_recorded = _recorded.Select((v, i) => (double)v * window[i]).ToList();
                //double[] Fourierdata = _recorded.Select(v => (v)).ToArray();
                //Fourier.ForwardReal(Fourierdata, Fourierdata.Length - 2, FourierOptions.Matlab); ;
                //var s = windowsize * (1.0 / 8000.0);
                ////var point = Fourierdata.Take(Fourierdata.Count()).Select((v, index) =>
                ////       new DataPoint((double)index, v)
                ////).ToList();
                //var point = Fourierdata.Take(Fourierdata.Count() / 2).Select((v, index) =>new DataPoint((double)index / s,v)).ToList();

                //_lineSeries.Points.Clear();
                //_lineSeries.Points.AddRange(points);
                //line1.ItemsSource = points;
                //line2.ItemsSource = point;
                _recorded.Clear();
            }
        }