我想实施哈里斯角落探测器。我发现这个页面非常有用,因为它显示了如何使用基本的opencv函数(如gaussianBlur和Sobel)实现检测器: https://compvisionlab.wordpress.com/2013/03/02/harris-interest-point-detection-implementation-opencv/
现在我甚至想要实现高斯模糊和索贝尔。如果我在某些图像上运行我的Gaussian或Sobel,它可以工作但与我的角点检测器结合使用它不起作用。请有人帮帮我。完整的代码如下,thx。
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
using namespace cv;
using namespace std;
/// Global variables
Mat src, src_gray, dst;
int thresh = 200;
int max_thresh = 255;
char* source_window = "Source Image";
char* corners_window = "Corner Image";
/// Function header
void cornerHarris_demo(int, void*);
void cornerHarrisMe(int, int, double);
int xGradient(Mat, int, int);
int yGradient(Mat, int, int);
void SobelMe(Mat&,Mat&,int,int);
int borderCheck(int M, int x);
void SepGaussian(Mat&, Mat&, int, int);
/** @function main */
int main(int argc, char** argv)
{
/// Load source image and convert it to gray
src = imread("data/a-real-big-church.jpg", 1);
//Mat src_gray(src.size(), CV_8UC1);
cvtColor(src, src_gray, CV_BGR2GRAY);
/// Create a window and a trackbar
namedWindow(source_window, CV_WINDOW_AUTOSIZE);
createTrackbar("Threshold: ", source_window, &thresh, max_thresh, cornerHarris_demo);
imshow(source_window, src);
cornerHarris_demo(0, 0);
waitKey(0);
return(0);
}
/** @function cornerHarris_demo */
void cornerHarris_demo(int, void*)
{
Mat dst_norm, dst_norm_scaled;
/// Detector parameters
int blockSize = 2;
int apertureSize = 3;
double k = 0.04;
/// Detecting corners
cornerHarrisMe(blockSize, apertureSize, k);
/// Normalizing
normalize(dst, dst_norm, 0, 255, NORM_MINMAX, CV_32FC1, Mat());
convertScaleAbs(dst_norm, dst_norm_scaled);
/// Drawing a circle around corners
for (int j = 0; j < dst_norm.rows; j++)
{
for (int i = 0; i < dst_norm.cols; i++)
{
if ((int)dst_norm.at<float>(j, i) > thresh)
{
circle(dst_norm_scaled, Point(i, j), 5, Scalar(255), 2, 8, 0);
}
}
}
/// Showing the result
namedWindow(corners_window, CV_WINDOW_AUTOSIZE);
imshow(corners_window, dst_norm_scaled);
}
void cornerHarrisMe(int blockSize, int apertureSize, double k)
{
Mat x2y2, xy, mtrace, x_der, y_der, x2_der, y2_der, xy_der, x2g_der, y2g_der, xyg_der;
//1: calculate x and y derivative of image via Sobel
SobelMe(src_gray, x_der, 1, 0);
SobelMe(src_gray, y_der, 0, 1);
//2: calculate other three images in M
pow(x_der, blockSize, x2_der);
pow(y_der, blockSize, y2_der);
multiply(x_der, y_der, xy_der);
//3: gaussain
SepGaussian(x2_der, x2g_der, 1, 0);
SepGaussian(y2_der, y2g_der, 0, 1);
SepGaussian(xy_der, xyg_der, 1, 1);
//4. calculating R with k
multiply(x2g_der, y2g_der, x2y2);
multiply(xyg_der, xyg_der, xy);
pow((x2g_der + y2g_der), blockSize, mtrace);
dst = (x2y2 - xy) - k * mtrace;
}
// gradient in the x direction
int xGradient(Mat image, int x, int y)
{
return image.at<uchar>(y - 1, x - 1) +
2 * image.at<uchar>(y, x - 1) +
image.at<uchar>(y + 1, x - 1) -
image.at<uchar>(y - 1, x + 1) -
2 * image.at<uchar>(y, x + 1) -
image.at<uchar>(y + 1, x + 1);
}
// gradient in the y direction
int yGradient(Mat image, int x, int y)
{
return image.at<uchar>(y - 1, x - 1) +
2 * image.at<uchar>(y - 1, x) +
image.at<uchar>(y - 1, x + 1) -
image.at<uchar>(y + 1, x - 1) -
2 * image.at<uchar>(y + 1, x) -
image.at<uchar>(y + 1, x + 1);
}
void SobelMe(Mat& source, Mat& destination, int xOrder, int yOrder){
int gradX, gradY, sum;
destination = source.clone();
if (xOrder == 1 && yOrder == 0){
for (int y = 1; y < source.rows - 1; y++){
for (int x = 1; x < source.cols - 1; x++){
gradX = xGradient(source, x, y);
sum = abs(gradX);
sum = sum > 255 ? 255 : sum;
sum = sum < 0 ? 0 : sum;
destination.at<uchar>(y, x) = sum;
}
}
}
else if (xOrder == 0 && yOrder == 1){
for (int y = 1; y < source.rows - 1; y++){
for (int x = 1; x < source.cols - 1; x++){
gradY = yGradient(source, x, y);
sum = abs(gradY);
sum = sum > 255 ? 255 : sum;
sum = sum < 0 ? 0 : sum;
destination.at<uchar>(y, x) = sum;
}
}
}
else if (xOrder == 1 && yOrder == 1)
for (int y = 1; y < source.rows - 1; y++){
for (int x = 1; x < source.cols - 1; x++){
gradX = xGradient(source, x, y);
gradY = yGradient(source, x, y);
sum = abs(gradX) + abs(gradY);
sum = sum > 255 ? 255 : sum;
sum = sum < 0 ? 0 : sum;
destination.at<uchar>(y, x) = sum;
}
}
}
int borderCheck(int M, int x){
if (x < 0)
return -x - 1;
if (x >= M)
return 2 * M - x - 1;
return x;
}
void SepGaussian(Mat& source, Mat& desination, int sigmaX, int sigmaY){
// coefficients of 1D gaussian kernel with sigma = 1
double coeffs[] = { 0.0545, 0.2442, 0.4026, 0.2442, 0.0545 };
Mat tempX, tempY;
float sum, x1, y1;
desination = source.clone();
tempY = source.clone();
tempX = source.clone();
// along y - direction
if (sigmaX == 0 && sigmaY == 1){
for (int y = 0; y < source.rows; y++){
for (int x = 0; x < source.cols; x++){
sum = 0.0;
for (int i = -2; i <= 2; i++){
y1 = borderCheck(source.rows, y - i);
sum = sum + coeffs[i + 2] * source.at<uchar>(y1, x);
}
desination.at<uchar>(y, x) = sum;
}
}
}
// along x - direction
else if (sigmaX == 1 && sigmaY == 0){
for (int y = 0; y < source.rows; y++){
for (int x = 0; x < source.cols; x++){
sum = 0.0;
for (int i = -2; i <= 2; i++){
x1 = borderCheck(source.cols, x - i);
sum = sum + coeffs[i + 2] * source.at<uchar>(y, x1);
}
desination.at<uchar>(y, x) = sum;
}
}
}
// along xy - direction
else if (sigmaX == 1 && sigmaY == 1){
for (int y = 0; y < source.rows; y++){
for (int x = 0; x < source.cols; x++){
sum = 0.0;
for (int i = -2; i <= 2; i++){
y1 = borderCheck(source.rows, y - i);
sum = sum + coeffs[i + 2] * source.at<uchar>(y1, x);
}
tempY.at<uchar>(y, x) = sum;
}
}
for (int y = 0; y < source.rows; y++){
for (int x = 0; x < source.cols; x++){
sum = 0.0;
for (int i = -2; i <= 2; i++){
x1 = borderCheck(source.cols, x - i);
sum = sum + coeffs[i + 2] * tempY.at<uchar>(y, x1);
}
desination.at<uchar>(y, x) = sum;
}
}
}
}
结果: Here is the a picture of the Result.
结果现在是另一种方式,它检测到没有角落的区域。 如果有问题,请随时问我。