提取图像中颜色交界处的坐标

以你之姓@ 2022-12-15 12:39 164阅读 0赞

# 简介 #

有时候需要提取图像颜色交界处的坐标，有个比较巧妙的思路是先做图像增强，通过去噪，连通域等处理，分为黑白二值图，然后再用3\*3的均值滤波将图像处理，原来纯白或者纯黑的地方还是纯色，但是交界处就不再是纯白或者纯黑了，利用这点可以提取出图像的交界点的坐标。  
如下图为黑白二值图，边界为黑白交界处的直线，若要提取边界的坐标可以通过一个3\*3的均值滤波作用，作用后可以得到图2（交界处不再是纯白或者纯黑）。  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA_size_16_color_FFFFFF_t_70_pic_center]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA_size_16_color_FFFFFF_t_70_pic_center 1]

# 以下图为例计算其黑白交界处的坐标 #

![示例图点击下载][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA_size_16_color_FFFFFF_t_70_pic_center 2]  
[示例图点击下载][Link 1]

#include<iostream>
    #include <opencv2\imgproc\imgproc.hpp>
    #include<opencv2\opencv.hpp>
    #include<opencv2\core\core.hpp>
    #include <opencv2\highgui\highgui.hpp>
    //#include <tools.cpp>
    
    using namespace std;
    using namespace cv;
    
    int main()
    { 
    	Mat src, srcGray;
    	src = cv::imread("C:\\Users\\Administrator\\Desktop\\test.jpg");
    	cv::cvtColor(src, srcGray, COLOR_RGB2GRAY);  // 转灰度图 
    	//........
    	//图像增强,以下图像需要二值化为0，255
    	//........
    
    	int i, j,counts=0;
    	float means;
    	int *Rows = (int*)malloc(srcGray.rows*srcGray.cols*sizeof(int));
    	int *Cols = (int*)malloc(srcGray.rows*srcGray.cols*sizeof(int));
    	memset(Rows, 0, srcGray.rows*srcGray.cols*sizeof(int));
    	memset(Cols, 0, srcGray.rows*srcGray.cols*sizeof(int));
    
    	for (i = 1; i < srcGray.rows - 1; i++) { 
    		for (j = 1; j < srcGray.cols - 1; j++) { 
    			// 3*3均值滤波
    			means = (srcGray.at<uchar>(i - 1, j - 1) + srcGray.at<uchar>(i - 1, j) + srcGray.at<uchar>(i - 1, j + 1)
    				+ srcGray.at<uchar>(i, j - 1) + srcGray.at<uchar>(i, j) + srcGray.at<uchar>(i, j + 1)
    				+ srcGray.at<uchar>(i + 1, j - 1) + srcGray.at<uchar>(i + 1, j) + srcGray.at<uchar>(i + 1, j + 1)) / 9.0;
    
    			// 均值滤波后像素值不为0或者255的是交界处
    			if (means>0 && means < 255)
    			{ 
    				Rows[counts] = i;
    				Cols[counts] = j;
    				counts += 1;
    				printf("(%d,%d),", i,j);
    			}
    		}
    	}
    	
    	free(Rows);
    	free(Cols);
    	return 0;
    }

输出的部分坐标点  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA_size_16_color_FFFFFF_t_70_pic_center 3]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA_size_16_color_FFFFFF_t_70_pic_center]: /images/20221123/1bd9dd583a024dce86f03a87ca438333.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221123/4288f668296b414884dafc42e0466f74.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA_size_16_color_FFFFFF_t_70_pic_center 2]: /images/20221123/dc40c5f0d08947f2b54ab024f1975801.png
[Link 1]: https://img-blog.csdnimg.cn/20201016161022878.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA==,size_16,color_FFFFFF,t_70#pic_center
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MzE2MjI0MA_size_16_color_FFFFFF_t_70_pic_center 3]: /images/20221123/6907df0659e846459c218ad23f43e466.png