OpenCV实现低对比度图像脏污区域检测

#include <iostream>
#include <opencv2\imgcodecs.hpp>
#include <opencv2\core.hpp>
#include <opencv2\imgproc.hpp>
#include <opencv2\highgui.hpp>
#include <vector>

int main()
{
	using namespace cv;

	std::string strImgFile = "C:\\Temp\\common\\Workspace\\Opencv\\images\\led1.jpg";
	Mat mSrc = imread(strImgFile);

	CV_Assert(mSrc.empty() == false);

	Mat mSrc2 = mSrc.clone();

	CV_Assert(mSrc2.empty() == false);

	Mat mGray;
	cvtColor(mSrc, mGray, COLOR_BGR2GRAY);

	GaussianBlur(mGray, mGray, Size(5, 5), 1.0);
	Mat mGray2 = mGray.clone();

	CV_Assert(mGray.empty() == false);
	imshow("gray", mGray.clone());

	//方法1：利用梯度变化检测缺陷
	Mat mSobelX, mSobelY;
	Sobel(mGray, mSobelX, CV_16S, 1, 0, 7);
	Sobel(mGray, mSobelY, CV_16S, 0, 1, 7);
	convertScaleAbs(mSobelX, mSobelX);
	convertScaleAbs(mSobelY, mSobelY);

	Mat mEdge;
	addWeighted(mSobelX, 1, mSobelY, 1, 0, mEdge);
	imshow("edge", mEdge);

	Mat mThresh;
	threshold(mEdge, mThresh, 0, 255, THRESH_BINARY | THRESH_OTSU);
	imshow("thresh", mThresh);

	Mat kernel1 = getStructuringElement(MORPH_RECT, Size(11, 11));
	CV_Assert(kernel1.empty() == false);

	Mat mMorph;
	morphologyEx(mThresh, mMorph, MORPH_ERODE, kernel1);
	imshow("erode", mMorph);

	Mat kernel2 = getStructuringElement(MORPH_RECT, Size(5, 5));
	morphologyEx(mMorph, mMorph, MORPH_DILATE, kernel2);
	imshow("dilate", mMorph);

	std::vector<std::vector<Point>> contours;
	findContours(mMorph, contours, RETR_EXTERNAL, CHAIN_APPROX_NONE);

	for (int i = 0; i < contours.size(); i++)
	{
		float area = contourArea(contours[i]);
		if (area > 200)
		{
			drawContours(mSrc, contours, i, Scalar(0, 0, 255));
		}
	}

	imshow("result1", mSrc.clone());

	//方法2： 利用局部直方图均衡化方法检测缺陷
	Ptr<CLAHE> ptrCLAHE = createCLAHE(20, Size(30, 30));
	ptrCLAHE->apply(mGray2, mGray2);
	imshow("equalizeHist", mGray2);

	Mat mThresh2;
	threshold(mGray2, mThresh2, 0, 255, THRESH_BINARY_INV | THRESH_OTSU);
	CV_Assert(mThresh2.empty() == false);
	imshow("thresh", mThresh2);

	Mat kernel2_1 = getStructuringElement(MORPH_RECT, Size(9, 9));
	Mat mMorph2;
	morphologyEx(mThresh2, mMorph2, MORPH_ERODE, kernel2_1);

	CV_Assert(mMorph2.empty() == false);

	imshow("morph2", mMorph2);

	std::vector<std::vector<Point>> contours2;
	findContours(mMorph2, contours2, RETR_EXTERNAL, CHAIN_APPROX_NONE);

	for (int i = 0; i < contours2.size(); i++)
	{
		float area = contourArea(contours2[i]);
		if (area > 200)
		{
			drawContours(mSrc2, contours2, i, Scalar(0, 0, 255));
		}
	}

	imshow("result2", mSrc2);

	waitKey(0);
	destroyAllWindows();

	system("pause");
	return 0;
}