第五章 用生态学过滤方法改变图像
这一章我们讨论：
用形态过滤器磨损和扩大图像用形态过滤器打开和关闭图像用形态过滤器做边缘检测和角点检测用水印分割图像用抓取切割算法提取前景中物体
到google上找到了书对应的代码下载了，然后条码的边缘检测有了点想法。
1 /*------------------------------------------------------------------------------------------*\ 2 This file contains material supporting chapter 5 of the cookbook: 3 Computer Vision Programming using the OpenCV Library. 4 by Robert Laganiere, Packt Publishing, 2011. 5 6 This program is free software; permission is hereby granted to use, copy, modify, 7 and distribute this source code, or portions thereof, for any purpose, without fee, 8 subject to the restriction that the copyright notice may not be removed 9 or altered from any source or altered source distribution. 10 The software is released on an as-is basis and without any warranties of any kind. 11 In particular, the software is not guaranteed to be fault-tolerant or free from failure. 12 The author disclaims all warranties with regard to this software, any use, 13 and any consequent failure, is purely the responsibility of the user. 14 15 Copyright (C) 2010-2011 Robert Laganiere, www.laganiere.name 16 \*------------------------------------------------------------------------------------------*/ 17 18 #include19 #include 20 #include 21 #include "morphoFeatures.h" 22 23 int main() 24 { 25 // Read input image 26 cv::Mat image= cv::imread("C:/testdir/barcode5.jpg",0); 27 if (!image.data) 28 return 0; 29 30 // Display the image 31 // cv::namedWindow("Image"); 32 cv::imshow("Image",image); 33 34 // Create the morphological features instance 35 MorphoFeatures morpho; 36 morpho.setThreshold(40); 37 38 // Get the edges 39 cv::Mat edges; 40 edges= morpho.getEdges(image); 41 42 // Display the edge image 43 cv::namedWindow("Edge Image"); 44 cv::imshow("Edge Image",edges); 45 46 // Get the corners 47 morpho.setThreshold(-1); 48 cv::Mat corners; 49 corners= morpho.getCorners(image); 50 cv::morphologyEx(corners,corners,cv::MORPH_TOPHAT,cv::Mat()); 51 cv::threshold(corners, corners, 40, 255, cv::THRESH_BINARY_INV); 52 53 // Display the corner image 54 cv::namedWindow("Corner Image"); 55 cv::imshow("Corner Image",corners); 56 57 // Display the corner on the image 58 morpho.drawOnImage(corners,image); 59 cv::namedWindow("Corners on Image"); 60 cv::imshow("Corners on Image",image); 61 /* 62 // Read and display image of square 63 image= cv::imread("C:/testdir/square.jpg",0); 64 cv::namedWindow("Square Image"); 65 cv::imshow("Square Image",image); 66 67 // Creating the cross-shaped structuring element 68 cv::Mat cross(5,5,CV_8U,cv::Scalar(0)); 69 for (int i=0; i<5; i++) { 70 71 cross.at (2,i)= 1; 72 cross.at (i,2)= 1; 73 } 74 75 // Dilate with a cross 76 cv::Mat result; 77 cv::dilate(image,result,cross); 78 79 // Display the result 80 cv::namedWindow("Dilated square with cross"); 81 cv::imshow("Dilated square with cross",result); 82 83 // Creating the diamond-shaped structuring element 84 cv::Mat diamond(5,5,CV_8U,cv::Scalar(1)); 85 diamond.at (0,0)= 0; 86 diamond.at (0,1)= 0; 87 diamond.at (1,0)= 0; 88 diamond.at (4,4)= 0; 89 diamond.at (3,4)= 0; 90 diamond.at (4,3)= 0; 91 diamond.at (4,0)= 0; 92 diamond.at (4,1)= 0; 93 diamond.at (3,0)= 0; 94 diamond.at (0,4)= 0; 95 diamond.at (0,3)= 0; 96 diamond.at (1,4)= 0; 97 98 // Erode with a diamond 99 cv::Mat result2;100 cv::erode(result,result2,diamond);101 102 // Display the result103 cv::namedWindow("Eroded square with diamond");104 cv::imshow("Eroded square with diamond",result2);105 106 // Combine the images into one107 cv::Mat final(100,300,CV_8U);108 cv::Mat window= final(cv::Rect(0,0,100,100));109 image.copyTo(window);110 window= final(cv::Rect(100,0,100,100));111 result.copyTo(window);112 window= final(cv::Rect(200,0,100,100));113 result2.copyTo(window);114 115 // Display the combined result116 cv::namedWindow("Combined");117 cv::imshow("Combined",final);118 119 // Save combined result120 cv::imwrite("squares.bmp",final);121 */122 cv::waitKey();123 124 return 0;125 }
morphoFeatures.h:
1 /*------------------------------------------------------------------------------------------*\ 2 This file contains material supporting chapter 5 of the cookbook: 3 Computer Vision Programming using the OpenCV Library. 4 by Robert Laganiere, Packt Publishing, 2011. 5 6 This program is free software; permission is hereby granted to use, copy, modify, 7 and distribute this source code, or portions thereof, for any purpose, without fee, 8 subject to the restriction that the copyright notice may not be removed 9 or altered from any source or altered source distribution. 10 The software is released on an as-is basis and without any warranties of any kind. 11 In particular, the software is not guaranteed to be fault-tolerant or free from failure. 12 The author disclaims all warranties with regard to this software, any use, 13 and any consequent failure, is purely the responsibility of the user. 14 15 Copyright (C) 2010-2011 Robert Laganiere, www.laganiere.name 16 \*------------------------------------------------------------------------------------------*/ 17 18 #if !defined MORPHOF 19 #define MORPHOF 20 21 #include22 #include 23 24 class MorphoFeatures { 25 26 private: 27 28 // threshold to produce binary image 29 int threshold; 30 // structuring elements used in corner detection 31 cv::Mat cross; 32 cv::Mat diamond; 33 cv::Mat square; 34 cv::Mat x; 35 36 void applyThreshold(cv::Mat& result) { 37 38 // Apply threshold on result 39 if (threshold>0) 40 cv::threshold(result, result, threshold, 255, cv::THRESH_BINARY_INV); 41 } 42 43 public: 44 45 MorphoFeatures() : threshold(-1), cross(5,5,CV_8U,cv::Scalar(0)), 46 diamond(5,5,CV_8U,cv::Scalar(1)), 47 square(5,5,CV_8U,cv::Scalar(1)), 48 x(5,5,CV_8U,cv::Scalar(0)){ 49 50 // Creating the cross-shaped structuring element 51 for (int i=0; i<5; i++) { 52 53 cross.at (2,i)= 1; 54 cross.at (i,2)= 1; 55 } 56 57 // Creating the diamond-shaped structuring element 58 diamond.at (0,0)= 0; 59 diamond.at (0,1)= 0; 60 diamond.at (1,0)= 0; 61 diamond.at (4,4)= 0; 62 diamond.at (3,4)= 0; 63 diamond.at (4,3)= 0; 64 diamond.at (4,0)= 0; 65 diamond.at (4,1)= 0; 66 diamond.at (3,0)= 0; 67 diamond.at (0,4)= 0; 68 diamond.at (0,3)= 0; 69 diamond.at (1,4)= 0; 70 71 // Creating the x-shaped structuring element 72 for (int i=0; i<5; i++) { 73 74 x.at (i,i)= 1; 75 x.at (4-i,i)= 1; 76 } 77 } 78 79 void setThreshold(int t) { 80 81 threshold= t; 82 } 83 84 int getThreshold() const { 85 86 return threshold; 87 } 88 89 cv::Mat getEdges(const cv::Mat &image) { 90 91 // Get the gradient image 92 cv::Mat result; 93 cv::morphologyEx(image,result,cv::MORPH_GRADIENT,cv::Mat()); 94 95 // Apply threshold to obtain a binary image 96 applyThreshold(result); 97 98 return result; 99 }100 101 cv::Mat getCorners(const cv::Mat &image) {102 103 cv::Mat result;104 105 // Dilate with a cross 106 cv::dilate(image,result,cross);107 108 // Erode with a diamond109 cv::erode(result,result,diamond);110 111 cv::Mat result2;112 // Dilate with a X 113 cv::dilate(image,result2,x);114 115 // Erode with a square116 cv::erode(result2,result2,square);117 118 // Corners are obtained by differencing119 // the two closed images120 cv::absdiff(result2,result,result);121 122 // Apply threshold to obtain a binary image123 applyThreshold(result);124 125 return result;126 }127 128 void drawOnImage(const cv::Mat& binary, cv::Mat& image) {129 130 cv::Mat_ ::const_iterator it= binary.begin ();131 cv::Mat_ ::const_iterator itend= binary.end ();132 133 // for each pixel 134 for (int i=0; it!= itend; ++it,++i) {135 if (!*it)136 cv::circle(image,cv::Point(i%image.step,i/image.step),5,cv::Scalar(255,0,0));137 }138 }139 };140 141 142 #endif
用500万像素的手机拍条码，边缘检测后虽然条码里面很乱但条码边框（黑色）能够确定了。