OpenCV graphing

Copyright: Attribution, allow others to create paper-based, and must distribute paper (based on the original license agreement with the same license Creative Commons )

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color problem: Graphic color will be affected by the number of image channels. As the image is grayscale, color graphics then fail , it will only show a gray line on the picture.

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First, line line

prototype

void line(
	InputOutputArray img,
	Point pt1,
	Point pt2,
	const Scalar &color,
	int thickness=1,
	int lineType=LINE_8,
	int shift=0 
)

parameter

• img : image
• PT1 : starting point
• PT2 : end
• color：Scalar(b,g,r)
• thickness: the thickness of the thickness of the line. -1 can not be wrong.
• lineType: line types. See LineTypes.
• shift: shift, scale point coordinates.

Example: From a drawing (100,200) to (250,100) Blue Line

#include<opencv2/opencv.hpp>
using namespace cv;

int main()
{
	Mat dstImage=Mat::zeros(300,400,CV_8UC3);
	line(dstImage,Point(100,200),Point(250,100),Scalar(255,102,0));
	imshow("dstImage",dstImage);
	waitKey();
	return 0;
}

Second, the rectangle rect

prototype

void rectangle(
	InputOutputArray img,
	Point pt1,
	Point pt2,
	const Scalar &color,
	int thickness=1,
	int lineType=LINE_8,
	int shift=0 
)

parameter

• img : image
• PT1 : on the corner
• PT2 : another pair of corner
• color：Scalar(b,g,r)
• thickness: the thickness of the thickness of the line. When to -1 drawn solid.
• lineType: line types. See LineTypes.
• shift: shift, scale point coordinates.

Example: two pairs of draw a hollow rectangle corner points (100,200) (250,100) of

#include<opencv2/opencv.hpp>
using namespace cv;

int main()
{
	Mat dstImage=Mat::zeros(300,400,CV_8UC3);
	rectangle(dstImage,Point(100,200),Point(250,100),Scalar(255,102,0));
	imshow("dstImage",dstImage);
	waitKey();
	return 0;
}

Draw a filled rectangle corner points of two pairs (100,200) (250,100): Example

#include<opencv2/opencv.hpp>
using namespace cv;

int main()
{
	Mat dstImage=Mat::zeros(300,400,CV_8UC3);
	rectangle(dstImage,Point(100,200),Point(250,100),Scalar(255,102,0),-1);
	imshow("dstImage",dstImage);
	waitKey();
	return 0;
}