Measure the Length and Width of the bounding Box
This is only simple application of opencv but I don't know how to do it . I will apply this application to measure the dimension of the object(Height and Width). Look at this video what I want to do. http://www.youtube.com/watch?v=bcswZLwhTUI
Please look at this code if it is correct.
int main(int, char**)
{
Mat threshold_output;
vector<vector<Point> > contours;
vector<Vec4i> hierarchy;
RNG rng(12345);
CvCapture* capture = cvCaptureFromCAM(0);
cv::Mat frame; cv::Mat src_gray;
while(true) {
frame = cvQueryFrame( capture );
cvtColor( frame,src_gray, CV_BGR2GRAY ); // produces out2, a one-channel image (CV_8UC1)
blur( src_gray, src_gray, Size(11,11) );
threshold( src_gray, threshold_output, 100, 200, CV_THRESH_BINARY_INV);
findContours( threshold_output, contours, hierarchy,CV_RETR_EXTERNAL, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
/// Find the rotated rectangles and ellipses for each contour
vector<RotatedRect> minRect( contours.size() );
for( int i = 0; i < contours.size(); i++ )
{
minRect[i] = minAreaRect( Mat(contours[i]) );
}
/// Draw contours + rotated rects + ellipses
Mat drawing = Mat::zeros( threshold_output.size(), CV_8UC3 );
for( int i = 0; i< contours.size(); i++ )
{
Scalar color = Scalar( rng.uniform(0,0), rng.uniform(0,0), rng.uniform(250,250) );
// contour
drawContours( drawing, contours, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
// rotated rectangle
Point2f rect_points[4];
minRect[i].points( rect_points );
for(int j = 0; j < 4; j++ )
line( frame, rect_points[j], rect_points[(j+1)%4], color, 1, 8 );
}
namedWindow( "Contours", CV_WINDOW_AUTOSIZE );
imshow( "Contours", frame );
cvWaitKey(33);
}
return 0;
} `
what's the question exactly?
How can measure the bounding rect based on the contour I've detected ?