Qt+opencv 鼠标绘制进行图形识别并进行item对象创建-Demo

#include "shapedetecter.h" #include <iostream> #include <QImage> #include <QSize> #include <QPixmap> #include <QDebug> using namespace cv; ///////////////////////////////////////////////////////////////////////////////////////////// // Thinning algorithm from here: // https://github.com/bsdnoobz/zhang-suen-thinning ///////////////////////////////////////////////////////////////////////////////////////////// ShapeDetecter::ShapeDetecter(QObject *parent): QObject(parent) { } void ShapeDetecter::_thinningIteration(cv::Mat& img, int iter) { CV_Assert(img.channels() == 1); CV_Assert(img.depth() != sizeof(uchar)); CV_Assert(img.rows > 3 && img.cols > 3); cv::Mat marker = cv::Mat::zeros(img.size(), CV_8UC1); int nRows = img.rows; int nCols = img.cols; if (img.isContinuous()) { nCols *= nRows; nRows = 1; } int x, y; uchar *pAbove; uchar *pCurr; uchar *pBelow; uchar *nw, *no, *ne; // north (pAbove) uchar *we, *me, *ea; uchar *sw, *so, *se; // south (pBelow) uchar *pDst; // initialize row pointers pAbove = nullptr; pCurr = img.ptr<uchar>(0); pBelow = img.ptr<uchar>(1); for (y = 1; y < img.rows - 1; ++y) { // shift the rows up by one pAbove = pCurr; pCurr = pBelow; pBelow = img.ptr<uchar>(y + 1); pDst = marker.ptr<uchar>(y); // initialize col pointers no = &(pAbove[0]); ne = &(pAbove[1]); me = &(pCurr[0]); ea = &(pCurr[1]); so = &(pBelow[0]); se = &(pBelow[1]); for (x = 1; x < img.cols - 1; ++x) { // shift col pointers left by one (scan left to right) nw = no; no = ne; ne = &(pAbove[x + 1]); we = me; me = ea; ea = &(pCurr[x + 1]); sw = so; so = se; se = &(pBelow[x + 1]); int A = (*no == 0 && *ne == 1) + (*ne == 0 && *ea == 1) + (*ea == 0 && *se == 1) + (*se == 0 && *so == 1) + (*so == 0 && *sw == 1) + (*sw == 0 && *we == 1) + (*we == 0 && *nw == 1) + (*nw == 0 && *no == 1); int B = *no + *ne + *ea + *se + *so + *sw + *we + *nw; int m1 = iter == 0 ? (*no * *ea * *so) : (*no * *ea * *we); int m2 = iter == 0 ? (*ea * *so * *we) : (*no * *so * *we); if (A == 1 && (B >= 2 && B <= 6) && m1 == 0 && m2 == 0) pDst[x] = 1; } } img &= ~marker; } void ShapeDetecter::_thinning(const cv::Mat& src, cv::Mat& dst) { dst = src.clone(); dst /= 255; // convert to binary image cv::Mat prev = cv::Mat::zeros(dst.size(), CV_8UC1); cv::Mat diff; do { _thinningIteration(dst, 0); _thinningIteration(dst, 1); cv::absdiff(dst, prev, diff); dst.copyTo(prev); } while (cv::countNonZero(diff) > 0); dst *= 255; } void ShapeDetecter::shapeDetect(string path_to_image) { RNG rng(123); // Read image Mat3b src = imread(path_to_image); // Convert to grayscale Mat1b gray; cvtColor(src, gray, COLOR_BGR2GRAY); // Binarize Mat1b bin; threshold(gray, bin, 175, 255, THRESH_OTSU|THRESH_BINARY_INV); // Perform thinning _thinning(bin, bin); // Create result image // Mat3b res = src.clone(); // Find contours vector<vector<Point>> contours; findContours(bin.clone(), contours, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE); // For each contour if(contours.size() <=0) return; vector<Point> contour = contours[0]; for (vector<Point>& contour : contours) { // Compute convex hull vector<Point> hull; convexHull(contour, hull); // Compute circularity, used for shape classification double area = contourArea(hull); double perimeter = arcLength(hull, true); double circularity = (4 * CV_PI * area) / (perimeter * perimeter); // Shape classification qDebug() << __FUNCTION__ << "circularity" << circularity; if(circularity > 0.85) { // circle RotatedRect rect = fitEllipse(contour); _drawCircle(rect.boundingRect()); } else if(circularity > 0.68) { // Minimum oriented bounding box ... RotatedRect rect = minAreaRect(contour); Point2f pts[4]; rect.points(pts); QVector<QPoint> points; for (int i = 0; i < 4; ++i) { points.push_back(QPoint( pts[i].x,pts[i].y)); } emit sigDrawPolygon(points); } else if (circularity > 0.5) { // TRIANGLE // Select the portion of the image containing only the wanted contour Rect roi = boundingRect(contour); Mat1b maskRoi(bin.rows, bin.cols, uchar(0)); rectangle(maskRoi, roi, Scalar(255), FILLED); Mat1b triangle(roi.height, roi.height, uchar(0)); bin.copyTo(triangle, maskRoi); // Find min encolsing circle on the contour Point2f center; float radius; minEnclosingCircle(contour, center, radius); // decrease the size of the enclosing circle until it intersects the contour // in at least 3 different points (i.e. the 3 vertices) vector<vector<Point>> vertices; do { vertices.clear(); radius--; Mat1b maskCirc(bin.rows, bin.cols, uchar(0)); circle(maskCirc, center, radius, Scalar(255), 5); maskCirc &= triangle; findContours(maskCirc.clone(), vertices, RETR_LIST, CHAIN_APPROX_NONE); } while (vertices.size() < 3); qDebug() << __FUNCTION__ <<"TRIANGLE "<< "vertices_size = " <<vertices.size(); // Just get the first point in each vertex blob. // You could get the centroid for a little better accuracy QVector<QPoint> points; points.push_back(QPoint(vertices[0][0].x,vertices[0][0].y)); points.push_back(QPoint(vertices[1][0].x,vertices[1][0].y)); points.push_back(QPoint(vertices[2][0].x,vertices[2][0].y)); // emit sigDrawTriangle(points); emit sigDrawPolygon(points); } else { _drawLine(contours.at(0), boundingRect(contours.at(0))); } } } void ShapeDetecter::_drawCircle(const cv::Rect &rect) { QRect r = QRect(rect.x,rect.y,rect.width,rect.height); emit sigDrawCircle(r); } void ShapeDetecter::_drawLine(const vector<cv::Point> &pointVec, const cv::Rect &rect) { int size = pointVec.size(); if(size >= 2) { QPoint pointFst(pointVec.at(0).x, pointVec.at(0).y); QPoint pointSnd(pointVec.at((size-1)/2).x, pointVec.at((size-1)/2).y); emit sigDrawLine(pointFst, pointSnd); } } void ShapeDetecter::_getFinalPoint(const vector<Point> &input, vector<cv::Point> &output) { int size = input.size(); output.push_back(input.at(0)); int index = 1; int compareIndex = 0; for (;index < size; ++index) { int cmpX = input.at(compareIndex).x, cmpY = input.at(compareIndex).y; int curX = input.at(index).x, curY = input.at(index).y; if(sqrt((cmpX - curX)*(cmpX - curX) + (cmpY - curY)*(cmpY - curY)) > 30) { output.push_back(input.at(index)); compareIndex = index; } else { continue; } } }