samples/cpp/tutorial_code/ImgProc/Morphology_2.cpp#
Advanced morphology Transformations sample code 
Check the corresponding tutorial for more details
1/**
2 * @file Morphology_2.cpp
3 * @brief Advanced morphology Transformations sample code
4 * @author OpenCV team
5 */
6
7#include "opencv2/imgproc.hpp"
8#include "opencv2/imgcodecs.hpp"
9#include "opencv2/highgui.hpp"
10#include <iostream>
11
12using namespace cv;
13
14/// Global variables
15Mat src, dst;
16
17int morph_elem = 0;
18int morph_size = 0;
19int morph_operator = 0;
20int const max_operator = 4;
21int const max_elem = 3;
22int const max_kernel_size = 21;
23
24const char* window_name = "Morphology Transformations Demo";
25
26
27/** Function Headers */
28void Morphology_Operations( int, void* );
29
30/**
31 * @function main
32 */
33int main( int argc, char** argv )
34{
35 //![load]
36 CommandLineParser parser( argc, argv, "{@input | baboon.jpg | input image}" );
37 src = imread( samples::findFile( parser.get<String>( "@input" ) ), IMREAD_COLOR );
38 if (src.empty())
39 {
40 std::cout << "Could not open or find the image!\n" << std::endl;
41 std::cout << "Usage: " << argv[0] << " <Input image>" << std::endl;
42 return EXIT_FAILURE;
43 }
44 //![load]
45
46 //![window]
47 namedWindow( window_name, WINDOW_AUTOSIZE ); // Create window
48 //![window]
49
50 //![create_trackbar1]
51 /// Create Trackbar to select Morphology operation
52 createTrackbar("Operator:\n 0: Opening - 1: Closing \n 2: Gradient - 3: Top Hat \n 4: Black Hat", window_name, &morph_operator, max_operator, Morphology_Operations );
53 //![create_trackbar1]
54
55 //![create_trackbar2]
56 /// Create Trackbar to select kernel type
57 createTrackbar( "Element:\n 0: Rect - 1: Cross - 2: Ellipse - 3: Diamond", window_name,
58 &morph_elem, max_elem,
59 Morphology_Operations );
60 //![create_trackbar2]
61
62 //![create_trackbar3]
63 /// Create Trackbar to choose kernel size
64 createTrackbar( "Kernel size:\n 2n +1", window_name,
65 &morph_size, max_kernel_size,
66 Morphology_Operations );
67 //![create_trackbar3]
68
69 /// Default start
70 Morphology_Operations( 0, 0 );
71
72 waitKey(0);
73 return 0;
74}
75
76//![morphology_operations]
77/**
78 * @function Morphology_Operations
79 */
80void Morphology_Operations( int, void* )
81{
82 // Since MORPH_X : 2,3,4,5 and 6
83 //![operation]
84 int operation = morph_operator + 2;
85 //![operation]
86
87 Mat element = getStructuringElement( morph_elem, Size( 2*morph_size + 1, 2*morph_size+1 ), Point( morph_size, morph_size ) );
88
89 /// Apply the specified morphology operation
90 morphologyEx( src, dst, operation, element );
91 imshow( window_name, dst );
92}
93//![morphology_operations]