我建立了一个只打印属于较大段的点的函数。它使用pointPolygonTest,这是一个很棒的 OpenCV 函数,可以判断一个点是在给定轮廓的内部、外部还是边界。一探究竟:
// Gets only the biggest segments
Mat Morphology::threshSegments(Mat &src, double threshSize) {
// FindContours:
vector<vector<Point> > contours;
vector<Vec4i> hierarchy;
Mat srcBuffer, output;
src.copyTo(srcBuffer);
findContours(srcBuffer, contours, hierarchy, cv::RETR_CCOMP, cv::CHAIN_APPROX_TC89_KCOS);
vector<vector<Point> > allSegments;
// For each segment:
for (size_t i = 0; i < contours.size(); ++i) {
cv::drawContours(srcBuffer, contours, i, Scalar(200, 0, 0), 1, 8, hierarchy, 0, Point());
cv::Rect brect = cv::boundingRect(contours[i]);
cv::rectangle(srcBuffer, brect, Scalar(255, 0, 0));
int result;
vector<Point> segment;
for (unsigned int row = brect.y; row < brect.y + brect.height; ++row) {
for (unsigned int col = brect.x; col < brect.x + brect.width; ++col) {
result = pointPolygonTest(contours[i], Point(col, row), false);
if (result == 1 || result == 0) {
segment.push_back(Point(col, row));
}
}
}
allSegments.push_back(segment);
}
output = Mat::zeros(src.size(), CV_8U);
int totalSize = output.rows*output.cols;
for (int segmentCount = 0; segmentCount < allSegments.size(); ++segmentCount) {
vector<Point> segment = allSegments[segmentCount];
if(segment.size() > totalSize*threshSize){
for (int idx = 0; idx < segment.size(); ++idx) {
output.at<uchar>(segment[idx].y, segment[idx].x) = 255;
}
}
}
return output;
}