C++ C++;FFTW向前向后DFT值被包装
大家好,我的社区, 我对fftw库的dft算法有一个问题。 我所要做的就是向前和向后转换某个模式,以再次接收输入模式,当然稍后在转换之间会有某种过滤 所以,我的程序所做的是:C++ C++;FFTW向前向后DFT值被包装,c++,fftw,dft,C++,Fftw,Dft,大家好,我的社区, 我对fftw库的dft算法有一个问题。 我所要做的就是向前和向后转换某个模式,以再次接收输入模式,当然稍后在转换之间会有某种过滤 所以,我的程序所做的是: 创建一个测试信号 用1.0或0.5的值对测试信号进行滤波或“窗口化” 将测试信号复制到fftw_复杂数据类型 执行向前和向后dft 计算震级,这里称为相位 复制和调整数据以便于显示,最后通过OpenCV显示图像 我的问题是,当不使用过滤时,我的后向变换图像以某种方式被包装,我无法计算正确的幅度,这应该与我的输入图像/测试信
/***** parameters **************************************************************************/
int imSize = 256;
int imN = imSize * imSize;
char* interferogram = new char[imN];
double* spectrumReal = new double[imN];
double* spectrumImaginary = new double[imN];
double* outputReal = new double[imN];
double* outputImaginary = new double[imN];
double* phase = new double[imN];
char* spectrumRealChar = new char[imN];
char* spectrumImaginaryChar = new char[imN];
char* outputRealChar = new char[imN];
char* outputImaginaryChar = new char[imN];
char* phaseChar = new char[imN];
Mat interferogramMat = Mat(imSize, imSize, CV_8U, interferogram);
Mat spectrumRealCharMat = Mat(imSize, imSize, CV_8U, spectrumRealChar);
Mat spectrumImaginaryCharMat = Mat(imSize, imSize, CV_8U, spectrumImaginaryChar);
Mat outputRealCharMat = Mat(imSize, imSize, CV_8U, outputRealChar);
Mat outputImaginaryCharMat = Mat(imSize, imSize, CV_8U, outputImaginaryChar);
Mat phaseCharMat = Mat(imSize, imSize, CV_8U, phaseChar);
/***** compute interferogram ****************************************************************/
fill_n(interferogram, imN, 0);
double value = 0;
double window = 0;
for (int y = 0; y < imSize; y++)
{
for (int x = 0; x < imSize; x++)
{
value = 127.5 + 127.5 * cos((2*PI) / 10000 * (pow(double(x - imSize/2), 2) + pow(double(y - imSize/2), 2)));
window = 1;
value *= window;
interferogram[y * imSize + x] = (unsigned char)value;
}
}
/***** create fftw arays and plans **********************************************************/
fftw_complex* input;
fftw_complex* spectrum;
fftw_complex* output;
fftw_plan p_fw;
fftw_plan p_bw;
input = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * imN);
spectrum = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * imN);
output = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * imN);
p_fw = fftw_plan_dft_2d(imSize, imSize, input, spectrum, FFTW_FORWARD, FFTW_ESTIMATE);
p_bw = fftw_plan_dft_2d(imSize, imSize, spectrum, output, FFTW_BACKWARD, FFTW_ESTIMATE);
/***** copy data ****************************************************************************/
for (int i = 0; i < imN; i++)
{
input[i][0] = double(interferogram[i]) / 255.;
input[i][1] = 0.;
spectrum[i][0] = 0.;
spectrum[i][1] = 0.;
output[i][0] = 0.;
output[i][1] = 0.;
}
/***** FPS algorithm ************************************************************************/
fftw_execute(p_fw);
fftw_execute(p_bw);
for (int i = 0; i < imN; i++)
{
phase[i] = sqrt(pow(output[i][0], 2) + pow(output[i][1], 2));
}
/***** copy data ****************************************************************************/
for (int i = 0; i < imN; i++)
{
spectrumReal[i] = spectrum[i][0];
spectrumImaginary[i] = spectrum[i][1];
outputReal[i] = output[i][0] / imN;
outputImaginary[i] = output[i][1];
}
SaveCharImage(interferogram, imN, "01_interferogram_512px_8bit.raw");
SaveDoubleImage(spectrumReal, imN, "02_spectrum_real_512px_64bit.raw");
SaveDoubleImage(spectrumImaginary, imN, "03_spectrum_imaginary_512px_64bit.raw");
SaveDoubleImage(outputReal, imN, "03_output_real_512px_64bit.raw");
DoubleToCharArray(spectrumReal, spectrumRealChar, imSize);
DoubleToCharArray(spectrumImaginary, spectrumImaginaryChar, imSize);
DoubleToCharArray(outputReal, outputRealChar, imSize);
DoubleToCharArray(outputImaginary, outputImaginaryChar, imSize);
DoubleToCharArray(phase, phaseChar, imSize);
/***** show images **************************************************************************/
imshow("interferogram", interferogramMat);
imshow("spectrum real", spectrumRealCharMat);
imshow("spectrum imaginary", spectrumImaginaryCharMat);
imshow("out real", outputRealCharMat);
imshow("out imaginary", outputImaginaryCharMat);
imshow("phase", phaseCharMat);
int key = waitKey(0);
/****参数**************************************************************************/
int imSize=256;
int imN=imSize*imSize;
字符*干涉图=新字符[imN];
double*spectrumReal=新的double[imN];
double*SpectrumMaginary=新双精度[imN];
double*outputReal=新的double[imN];
double*OutputMaginary=新的双精度[imN];
双*相位=新双[imN];
char*spectrumRealChar=新字符[imN];
char*spectrumImaginaryChar=新字符[imN];
char*outputRealChar=新字符[imN];
char*outputImaginaryChar=新字符[imN];
char*phaseChar=新字符[imN];
Mat干涉图=Mat(imSize,imSize,CV_8U,干涉图);
Mat spectrumRealCharMat=Mat(imSize,imSize,CV_8U,spectrumRealChar);
Mat spectrumImaginaryCharMat=Mat(imSize,imSize,CV_8U,spectrumImaginaryChar);
Mat outputRealCharMat=Mat(imSize,imSize,CV_8U,outputRealChar);
Mat outputImaginaryCharMat=Mat(imSize,imSize,CV_8U,outputImaginaryChar);
Mat phaseCharMat=Mat(imSize,imSize,CV_8U,phaseChar);
/*****计算干涉图****************************************************************/
填充n(干涉图,imN,0);
双值=0;
双窗口=0;
对于(int y=0;ychar* interferogram = new char[imN];
...
double value = 0;
double window = 0;
for (int y = 0; y < imSize; y++)
{
for (int x = 0; x < imSize; x++)
{
value = 127.5 + 127.5 * cos((2*PI) / 10000 * (pow(double(x - imSize/2), 2) + pow(double(y - imSize/2), 2)));
window = 1;
value *= window;
interferogram[y * imSize + x] = (unsigned char)value;
}
}
outputReal[i] = output[i][0] / imN;
outputImaginary[i] = output[i][1];
outputReal[i] = output[i][0];
outputImaginary[i] = output[i][1];