find_borders.cpp

#include "find_borders.h"

#include "debug.h"

using namespace cv;

Rect find_borders(const Mat &image)
{
    Mat work = image.clone();
    vector<vector<Point> > contours;
    findContours(work, contours, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE);
    // Sort the contours in decreasing area
    sort(contours.begin(), contours.end(), [](const vector<Point>& c1, const vector<Point>& c2) {
        return contourArea(c1, false) > contourArea(c2, false);
    });
    if (contours.size() > 0) {
    	Rect r = boundingRect(contours[0]);
#if 0 || defined(DISPLAY_INTERMEDIATE_IMAGES)
    	Mat work = image.clone();
    	rectangle(work, r, Scalar(0, 0, 255));
    	display_image("Borders", work);
#endif /* DISPLAY_INTERMEDIATE_IMAGES */
        return r;
    }
    return Rect();
}