OPENCV connected domain related operations

1. Connected domain Inverse selection

When you use the Findcontours function of OpenCV to find a connected domain outline, you may need to use a selection counter-selection function similar to PS.

This section is described below:

In the Findcontours function, select the Cv_retr_ccomp two-level contour lookup in the mode parameter,

To construct a selection range for an inverse selection of image size

    VECTOR<CV::P oint> boundcontours (4);    boundcontours[0] = CV::P oint (00);    boundcontours[1] = CV::P oint (0, src.rows-1);    boundcontours[2] = CV::P oint (src.cols-1, src.rows-1);    boundcontours[3] = CV::P oint (src.cols-10);

intMain () {cv::mat src= Imread ("original. PNG",0); Vector&LT;VECTOR&LT;CV::P oint>>linecontours; Vector<cv::Vec4i>hierarchy;    Findcontours (SRC, linecontours, hierarchy, Cv_retr_ccomp, cv_chain_approx_simple); linecontours[0].clear (); Vector&LT;CV::P oint> boundcontours (4); boundcontours[0] = CV::P oint (0,0); boundcontours[1] = CV::P oint (0, src.rows-1); boundcontours[2] = CV::P oint (src.cols-1, src.rows-1); boundcontours[3] = CV::P oint (src.cols-1,0); linecontours[0] =boundcontours; Cv::mat temptimg (Scr.size (), Cv_8uc1,scalar (0)); Drawcontours (temptimg, Linecontours,-1, Scalar (255), -1);}

Original:

The results are as follows:

OPENCV connected domain related operations