Create Exercises_8_1.cpp

add exercise_8_1.cpp

Exercises_8_1.cpp

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+//Exercises at end of Chapter 8
+//1
+#include <opencv2/opencv.hpp>
+#include <iostream>
+
+using namespace cv;
+using namespace std;
+
+
+void help(const char **argv) {
+	cout << "\n\n"
+		<< "This program solves the Exercise 1 at the end of Chapter 8 \n"
+		<< "Call:\n"
+		<< argv[0] << " <path/video_name>\n\n"
+		<< "For example: ./" << argv[0] << " ../bike.avi\n"
+		<< endl;
+}
+
+int main( int argc, const char** argv )
+{
+	help(argv);
+	if(argc < 2) {
+		cout << "\nERROR: You had too few parameters.\n" << endl;
+		return -1;
+	}
+	/************************************************************************/
+	/* 1.  Create a program that 
+	(1) reads frames from a video, 
+	(2) turns the result to gray‐scale,  and 
+	(3) performs  Canny  edge  detection  on  the  image.  
+	Display  all  three stages of processing in three different windows, with each window appropriately
+	named for its function.
+	a.  Display  all  three  stages  of  processing  in  one  image.  (Hint:  create  another
+	image of the same height but three times the width as the video frame. Copy
+	the  images  into  this,  either  by  using  pointers  or  (more  cleverly)  by  creating
+	three new image headers that point to the beginning of and to one-third and
+	two-thirds of the way into the imageData. Then use Mat::copyTo().)
+	b.  Write  appropriate  text  labels  describing  the  processing  in  each  of  the  three
+	slots.*/
+	/************************************************************************/
+	VideoCapture capture(argv[1]); 
+	if(!capture.isOpened())
+		return 1;
+	double rate=capture.get(CV_CAP_PROP_FPS);
+	bool stop(false);
+	Mat MatFrame;
+	Mat MatGray;
+	Mat MatCanny;
+	int delay=1000/rate;
+	while(!stop)
+	{
+		if(!capture.read(MatFrame))
+			break;
+		//(1)
+		imshow("Raw Video",MatFrame);
+		//(2)
+		cvtColor(MatFrame,MatGray,COLOR_BGR2GRAY);
+		imshow("Gray Video",MatGray);
+		//(3)
+		Canny(MatGray,MatCanny,100,255);
+		imshow("Canny Video",MatCanny);
+		//question a
+		Mat MatAll(MatFrame.rows,3* MatFrame.cols  ,CV_8UC3,Scalar::all(0));
+		cvtColor(MatGray,MatGray,COLOR_GRAY2BGR);
+		cvtColor(MatCanny,MatCanny,COLOR_GRAY2BGR);
+		Mat MatSub = MatAll.colRange(0, MatFrame.cols);
+		MatFrame.copyTo(MatSub);
+		MatSub = MatAll.colRange( MatFrame.cols,2*MatFrame.cols);
+		MatGray.copyTo(MatSub);
+		MatSub = MatAll.colRange(2*MatFrame.cols,3*MatFrame.cols);
+		MatCanny.copyTo(MatSub);
+		//question b
+		Scalar color = CV_RGB(255,0,0);
+		putText(MatAll,"raw video",Point(50,30),CV_FONT_HERSHEY_DUPLEX,1.0f,color);
+		putText(MatAll,"gray video",Point(50+MatFrame.cols,30),CV_FONT_HERSHEY_DUPLEX,1.0f,color);
+		putText(MatAll,"canny video",Point(50+2*MatFrame.cols,30),CV_FONT_HERSHEY_DUPLEX,1.0f,color);
+		imshow("all Video",MatAll);
+		if(waitKey(delay)>=0)
+			stop=true;
+	}
+	capture.release();
+	waitKey();
+	getchar();
+	return 0;
+
+}