OpenCV3.0 Examples学习笔记（17）-morphology2.cpp-erode，dilate，morphologyEx函数实现数学形态学变换

#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui/highgui.hpp"
#include <stdlib.h>
#include <stdio.h>using namespace cv;static void help()
{printf("\nShow off image morphology: erosion, dialation, open and close\n""Call:\n   morphology2 [image]\n""This program also shows use of rect, ellipse and cross kernels\n\n");
printf( "Hot keys: \n""\tESC - quit the program\n""\tr - use rectangle structuring element\n""\te - use elliptic structuring element\n""\tc - use cross-shaped structuring element\n""\tSPACE - loop through all the options\n" );
}Mat src, dst;int element_shape = MORPH_RECT;//the address of variable which receives trackbar position update
int max_iters = 10;
int open_close_pos = 0;
int erode_dilate_pos = 0;// callback function for open/close trackbar
static void OpenClose(int, void*)
{int n = open_close_pos - max_iters;int an = n > 0 ? n : -n;Mat element = getStructuringElement(element_shape, Size(an*2+1, an*2+1), Point(an, an) );if( n < 0 )morphologyEx(src, dst, MORPH_OPEN, element);elsemorphologyEx(src, dst, MORPH_CLOSE, element);imshow("Open/Close",dst);
}// callback function for erode/dilate trackbar
static void ErodeDilate(int, void*)
{int n = erode_dilate_pos - max_iters;int an = n > 0 ? n : -n;Mat element = getStructuringElement(element_shape, Size(an*2+1, an*2+1), Point(an, an) );if( n < 0 )erode(src, dst, element);elsedilate(src, dst, element);imshow("Erode/Dilate",dst);
}int main( int argc, char** argv )
{char* filename = argc == 2 ? argv[1] : (char*)"../data/baboon.jpg";if( (src = imread(filename,1)).empty() )return -1;help();//create windows for output imagesnamedWindow("Open/Close",1);namedWindow("Erode/Dilate",1);open_close_pos = erode_dilate_pos = max_iters;createTrackbar("iterations", "Open/Close",&open_close_pos,max_iters*2+1,OpenClose);createTrackbar("iterations", "Erode/Dilate",&erode_dilate_pos,max_iters*2+1,ErodeDilate);for(;;){int c;OpenClose(open_close_pos, 0);ErodeDilate(erode_dilate_pos, 0);c = waitKey(0);if( (char)c == 27 )break;if( (char)c == 'e' )element_shape = MORPH_ELLIPSE;else if( (char)c == 'r' )element_shape = MORPH_RECT;else if( (char)c == 'c' )element_shape = MORPH_CROSS;else if( (char)c == ' ' )element_shape = (element_shape + 1) % 3;}return 0;
}