Revision history [back]

Its nothing but you have to draw ellipse() but need to adjust the parameters, like

center=your image centre
axes = Size(img.cols/2,img.rows/2) // width/2 X height/2
angle=0;
startAngle=0;
endAngle=360;

Now raw ellipse using above

ellipse(img,Point(img.cols/2,img.rows/2), Size(img.cols/2,img.rows/2),0,0,360, Scalar(0,0,255), 2, 8,0);

Its nothing but you have to draw ellipse() but need to adjust the parameters, like

center=your image centre
axes = Size(img.cols/2,img.rows/2) // width/2 X height/2
angle=0;
startAngle=0;
endAngle=360;

Now raw draw ellipse using above

ellipse(img,Point(img.cols/2,img.rows/2), Size(img.cols/2,img.rows/2),0,0,360, Scalar(0,0,255), 2, 8,0);