Questions about the boundary storage type-CodePudding

I've tested, give a vector Type assignment, then use drawcontour draw, is according to the points in order to draw out the closing of the polygon, also is a canny boundary detection, then vector< findcontour; Point> Type, drawcontour why has not closed,
There is a problem, clearly seems to be closed boundary, choose one of the points with pointpolygontest test result does not, only to get the correct result, after convexhull
Forget the great god answer

CodePudding user response:

Can you give a look at the image processing results, canny out there are a lot of tiny burrs, I think this could be the cause

CodePudding user response:

Fyi:

 const static Scalar colors [15]={
CV_RGB (0, 0128), 
CV_RGB (0128, 0), 
CV_RGB (0128128), 
CV_RGB (128, 0, 0), 
CV_RGB (128, 0128), 
CV_RGB (128128, 0), 
CV_RGB (128128128), 
CV_RGB (160160160), 
CV_RGB (0, 0255), 
CV_RGB (0255, 0), 
CV_RGB (0255255), 
CV_RGB (255, 0, 0), 
CV_RGB (255, 0255), 
CV_RGB (255255, 0), 
CV_RGB (255255255), 
}; 
Mat img, gray, bw; 
VectorVector Contours. 
FindContours (bw, contours, hierarchy, RETR_EXTERNAL CHAIN_APPROX_SIMPLE); 
if (! Contours. The empty () & amp; & ! Hierarchy. The empty ()) {
Independence idx=0; 
n=0; 
Vector Approx. 
For (; Idx>=0; Independence idx=hierarchy [independence idx] [0]) {
Color=colors [15] independence idx %; 
//drawContours (smallImg, contours, independence idx, color, and 1, 8, hierarchy); 
ApproxPolyDP (Mat (contours [independence idx]), approx, arcLength (Mat (contours [independence idx]), true) * 0.005, true);//0.005 will flash straightening coefficient 
Const Point * p=& amp; Approx [0]. 
Int m=(int) approx. The size (); 
Polylines (smallImg, & amp; P, & amp; M, 1, true, color); 
Circle (smallImg, Point (p [0]. X, p [0]. Y), 2, color); 
Circle (smallImg, Point (p [1]. X, p [1]. Y), 1, color); 

n++; 
If (1==n) {
Maxrect=boundingRect (Mat (contours [independence idx])); 
} else {
Brect=boundingRect (Mat (contours [independence idx])); 
CvRect Mr (maxrect), br (brect); 
Maxrect=cvMaxRect (& amp; Mr, & amp; Br); 
} 
} 
Circle (smallImg, Point (maxrect. X + maxrect. Width/2, maxrect. Y + maxrect. Height/2), 2, CV_RGB (0, 255)); 
} 
Imshow (" display ", smallImg); 
WaitKey (0);