OpenCV GUI basic operation, callback function, progress bar, cropping image, etc.

The code is reproduced, the source can not find, not affixed to the

Tool Bar Progress bar:

//ConvertColor.cpp : Defines the entry point of the console application. #include "stdafx.h" #include <iostream> #include <opencv2/highgui/highgui.hpp> #include <opencv2/ imgproc/imgproc.hpp> #pragma comment (lib, "Opencv_core2410d.lib") #pragma comment (lib, "Opencv_highgui2410d.lib ") #pragma comment (lib," Opencv_imgproc2410d.lib ") using namespace std;using namespace cv;//Global Variablesco NST int slider_max = 100;int slider; Mat img;//Callback function for TrackBar eventvoid on_trackbar (int pos, void *) {Mat img_converted;if (pos > 0) Cvtcolor (IMG, img_converted, cv_rgb2gray); else img_converted = Img;imshow ("Trackbar app", img_converted);} int main () {img = Imread ("swan.jpg"), Namedwindow ("Trackbar app"), Imshow ("Trackbar app", img); slider = 0;createtrackbar ( "RGB <-> grayscale", "Trackbar app", &slider, Slider_max, On_trackbar); while (char (Waitkey (1)! = ' Q ') {}return 0;} 

Effect:

Image Trimming Code:

ConvertColor.cpp: Defines the entry point of the console application. #include "stdafx.h" #include <iostream> #include <opencv2/highgui/highgui.hpp> #include <opencv2/ imgproc/imgproc.hpp> #pragma comment (lib, "Opencv_core2410d.lib") #pragma comment (lib, "Opencv_highgui2410d.lib  ") #pragma comment (lib," Opencv_imgproc2410d.lib ") using namespace std;using namespace cv;//Global variables//  Flags updated according to left mouse button Activitybool Ldown = False, Lup = false;//Original Imagemat img;//starting and ending points of the user ' s selectionpoint corner1, corner2;//roirect box;//Callback function for mouse Eventsstati c void Mouse_callback (int event, int x, int y, int, void *) {//When the left mouse button was pressed, record its position and save it in corner1if (event = = Event_lbuttondown) {Ldown = true;corner1.x = X;corner1.y = Y;cout << "Corner 1 reco rded at "<< corner1 << Endl;} When the left mouse button was released, record its position and save it in COrner2if (event = = Event_lbuttonup) {//Also check if user selection is bigger than-pixels (jut for fun!) if (ABS (x-corner1.x) > && abs (Y-CORNER1.Y) >) {lup = true;corner2.x = X;corner2.y = Y;cout << "Corner 2 recorded at" << corner2 << Endl << Endl;} Else{cout << "Please select a bigger region" << Endl;ldown = false;}} Update the box showing the selected region as the user drags the Mouseif (Ldown = = True && Lup = False) {point P T;pt.x = X;pt.y = y; Mat local_img = Img.clone () rectangle (local_img, Corner1, PT, Scalar (0, 0, 255)), Imshow ("cropping app", local_img);} Define ROI and crop it out when both corners has been selectedif (Ldown = True && Lup = True) {Box.width = ABS (corner1.x-corner2.x); box.height = ABS (CORNER1.Y-CORNER2.Y); box.x = min (corner1.x, corner2.x); box.y = min (corner1.y, C ORNER2.Y);//Make an image out of just the selected ROI and display it in a new Windowmat crop (img, box); Namedwindow ("CRop "); Imshow (" Crop ", Crop); Ldown = False;lup = false;}} int main () {img = Imread ("swan.jpg"), Namedwindow ("cropping app"), Imshow ("Cropping App", IMG);//Set the mouse event Callba CK functionsetmousecallback ("cropping app", mouse_callback);//Exit by pressing ' Q ' while (char (Waitkey (1))! = ' Q ') {} return 0;}

Cutting effect:

OpenCV GUI basic operation, callback function, progress bar, cropping image, etc.