下图是OpenCV 自带例子的修改版本。
结果:
代码实现:
#include
#include "opencv2/imgproc.hpp"
#include "opencv2/imgcodecs.hpp"
#include
using namespace cv;
using namespace std;
void calcPSF(Mat& outputImg, Size filterSize, int len, double theta);
void fftshift(const Mat& inputImg, Mat& outputImg);
void filter2DFreq(const Mat& inputImg, Mat& outputImg, const Mat& H);
void calcWnrFilter(const Mat& input_h_PSF, Mat& output_G, double nsr);
void edgetaper(const Mat& inputImg, Mat& outputImg, double gamma = 5.0, double beta = 0.2);
int LEN = 50;
int THETA = 360;
int snr = 8000;
Mat imgIn;
Rect roi;
static void onChange(int pos, void* userInput);
int main(int argc, char *argv[])
{
string strInFileName = "529g.tif";
imgIn = imread(strInFileName, IMREAD_GRAYSCALE);
if (imgIn.empty()) //check whether the image is loaded or not
{
cout << "ERROR : Image cannot be loaded..!!" << endl;
return -1;
}
imshow( "src", imgIn );
// it needs to process even image only
roi = Rect(0, 0, imgIn.cols & -2, imgIn.rows & -2);
imgIn = imgIn(roi);
cv::namedWindow("inverse");
createTrackbar("LEN", "inverse", &LEN, 200, onChange, &imgIn);
onChange(0, 0);
createTrackbar("THETA", "inverse", &THETA, 360, onChange, &imgIn);
onChange(0, 0);
createTrackbar("snr", "inverse", &snr, 10000, onChange, &imgIn);
onChange(0, 0);
imshow( "inverse", imgIn );
cv::waitKey(0);
return 0;
}
void calcPSF(Mat& outputImg, Size filterSize, int len, double theta)
{
Mat h(filterSize, CV_32F, Scalar(0));
Point point(filterSize.width / 2, filterSize.height / 2);
ellipse(h, point, Size(0, cvRound(float(len) / 2.0)), 90.0 - theta,
0, 360, Scalar(255), FILLED);
Scalar summa = sum(h);
outputImg = h / summa[0];
Mat tmp;
normalize(outputImg, tmp, 1,0, CV_MINMAX);
imshow( "psf", tmp);
}
void fftshift(const Mat& inputImg, Mat& outputImg)
{
outputImg = inputImg.clone();
int cx = outputImg.cols / 2;
int cy = outputImg.rows / 2;
Mat q0(outputImg, Rect(0, 0, cx, cy));
Mat q1(outputImg, Rect(cx, 0, cx, cy));
Mat q2(outputImg, Rect(0, cy, cx, cy));
Mat q3(outputImg, Rect(cx, cy, cx, cy));
Mat tmp;
q0.copyTo(tmp);
q3.copyTo(q0);
tmp.copyTo(q3);
q1.copyTo(tmp);
q2.copyTo(q1);
tmp.copyTo(q2);
}
void filter2DFreq(const Mat& inputImg, Mat& outputImg, const Mat& H)
{
Mat planes[2] = { Mat_
Mat complexI;
merge(planes, 2, complexI);
dft(complexI, complexI, DFT_SCALE);
Mat planesH[2] = { Mat_
Mat complexH;
merge(planesH, 2, complexH);
Mat complexIH;
mulSpectrums(complexI, complexH, complexIH, 0);
idft(complexIH, complexIH);
split(complexIH, planes);
outputImg = planes[0];
}
void calcWnrFilter(const Mat& input_h_PSF, Mat& output_G, double nsr)
{
Mat h_PSF_shifted;
fftshift(input_h_PSF, h_PSF_shifted);
Mat planes[2] = { Mat_
Mat complexI;
merge(planes, 2, complexI);
dft(complexI, complexI);
split(complexI, planes);
Mat denom;
pow(abs(planes[0]), 2, denom);
denom += nsr;
divide(planes[0], denom, output_G);
}
void edgetaper(const Mat& inputImg, Mat& outputImg, double gamma, double beta)
{
int Nx = inputImg.cols;
int Ny = inputImg.rows;
Mat w1(1, Nx, CV_32F, Scalar(0));
Mat w2(Ny, 1, CV_32F, Scalar(0));
float* p1 = w1.ptr
float* p2 = w2.ptr
float dx = float(2.0 * CV_PI / Nx);
float x = float(-CV_PI);
for (int i = 0; i < Nx; i++)
{
p1[i] = float(0.5 * (tanh((x + gamma / 2) / beta) - tanh((x - gamma / 2) / beta)));
x += dx;
}
float dy = float(2.0 * CV_PI / Ny);
float y = float(-CV_PI);
for (int i = 0; i < Ny; i++)
{
p2[i] = float(0.5 * (tanh((y + gamma / 2) / beta) - tanh((y - gamma / 2) / beta)));
y += dy;
}
Mat w = w2 * w1;
multiply(inputImg, w, outputImg);
}
// Trackbar call back function
static void onChange(int , void* userInput)
{
Mat imgOut;
//Hw calculation (start)
Mat Hw, h;
calcPSF(h, roi.size(), LEN, (double)THETA);
calcWnrFilter(h, Hw, 1.0 / double(snr));
//Hw calculation (stop)
imgIn.convertTo(imgIn, CV_32F);
edgetaper(imgIn, imgIn);
// filtering (start)
filter2DFreq(imgIn(roi), imgOut, Hw);
// filtering (stop)
imgOut.convertTo(imgOut, CV_8U);
normalize(imgOut, imgOut, 0, 255, NORM_MINMAX);
// imwrite("result.jpg", imgOut);
imshow("inverse", imgOut);
}