一、序言：
该教程承接上文的离散傅里叶变换，用于进行离散傅里叶逆变换。
二、设计目标
对复数数组进行离散傅里叶逆变换，并生成可供使用的图像类。
三、详细步骤
输入：经傅里叶变换后产生的复数数组
输出：MyImage图像
定义：
static MyImage* Idft2(ComplexNumber *Scr,int const width,int const height);
实现：MyImage* MyCV::Idft2(ComplexNumber *Scr, int width, int height)
{ int bytesPerLine = (width*8+31)/32*4; double* double_data = new double[width*height]; memset(double_data,0,sizeof(double_data)*sizeof(double)); //全部赋值为0 double fixed_factor_for_axisX = (2 * PI) / height; // evaluate i2π/N of i2πux/N, and store the value for computing efficiency double fixed_factor_for_axisY = (2 * PI) / width; // evaluate i2π/N of i2πux/N, and store the value for computing efficiency for (int x = 0; x<height; x++) { for (int y = 0; y<width; y++) { for (int u = 0; u<height; u++) { for (int v = 0; v<width; v++) { double powerU = u * x * fixed_factor_for_axisX; // evaluate i2πux/N double powerV = v * y * fixed_factor_for_axisY; // evaluate i2πux/N ComplexNumber cplTemp; cplTemp.SetValue(cos(powerU + powerV), sin(powerU + powerV)); double_data[y + x*width] = double_data[y + x*width] + ((Scr[v + u*width] * cplTemp).m_rl /(height*width)); } } } } unsigned char *idft2_data = new unsigned char[bytesPerLine*height];//存储处理后的数据 for(int i=0;i<height;i++) for(int j=0;j<width;j++) { idft2_data[i*bytesPerLine+j] = (unsigned char)double_data[i*width+j]; } return new MyImage(idft2_data,width,height,MyImage::format::GRAY8);}
至此，离散傅里叶逆变换的方法实现完成，效果图如下：
如果上述教程或代码中有任何错误，欢迎批评和指证。
转载于:https://www.cnblogs.com/akakakkk/p/8595156.html