I am working on software using OpenCV in C++ environment. The objective is to detect a boxing glove and draw a bounding box around gloves contours.
The problem I am running into is that the bounding box is drown more than once in fact multiple boxes are drawn. What I was trying to do over the past few days is to somehow eliminate the number of boxes drawn and have only one big bounding box drawn.
I was looking at some techniques to fill in the object int its whole which i believe would really help in this case.
Below I have posted the code i used to achieve the result displayed in the image:
vector<vector<Point> > contours;
vector<Vec4i> hierarchy;
vector<Vec3f> vecCircles;
vector<Vec3f>::iterator itrCircles;
while(1)
{
Mat frame;
cap >> frame; // get a new frame from camera
/////////////////////
Mat imgHSV;
cvtColor( frame, imgHSV, CV_BGR2HSV );
////////////////////
Mat blur_out;
GaussianBlur(imgHSV, blur_out, Size(1,1),2.0,2.0);
////////////////////
Mat range_out;
inRange(blur_out, Scalar(100, 100, 100), Scalar(120, 255, 255), range_out);
////////////////////
findContours(range_out, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
/// Approximate contours to polygons + get bounding rects and circles
vector<vector<Point> > contours_poly( contours.size() );
vector<Rect> boundRect( contours.size() );
vector<Point2f>center( contours.size() );
vector<float>radius( contours.size() );
for( int i = 0; i < contours.size(); i++ )
{
approxPolyDP( Mat(contours[i]), contours_poly[i], 3, true );
boundRect[i] = boundingRect( Mat(contours_poly[i]) );
}
/// Draw polygonal contour + bonding rects
Mat drawing = Mat::zeros( range_out.size(), CV_8UC3 );
for( int i = 0; i< contours.size(); i++ )
{
Scalar color = Scalar(255,0,255);
drawContours( drawing, contours_poly, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
rectangle( drawing, boundRect[i].tl(), boundRect[i].br(), color, 2, 8, 0 );
}
If anyone could suggest some tips or provide some source of information where i can find answers for my problem.
EDIT (quick update):
I managed to improve the output image quiet gradually to a point am quiet happy with the result. The Key was the usage of erode & dilation as well as in my findContours()
function. I changed the CV_RETR_TREE
to CV_RETR_EXTERNAL
. There were a few other minor things i tackled but the result is good:
Dont know if i should write this here or open new thread....But now I need some help with component labeling and extracting parameters such as center points and area. :)
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