I adapted this code to read the white rectangle with the word 23-1965
But, it does not detect it sees a lot of other side dishes, but not what interests me. Who tells me where I'm wrong? Also attach the image to be processed
/**
* Simple shape detector program.
* It loads an image and tries to find simple shapes (rectangle, triangle, circle, etc) in it.
* This program is a modified version of squares.cpp found in the OpenCV sample dir.
*/
include <opencv2 highgui="" highgui.hpp="">
include <opencv2 imgproc="" imgproc.hpp="">
include <cmath>
include <iostream>
using namespace std;
/* * Helper function to find a cosine of angle between vectors * from pt0->pt1 and pt0->pt2 */ static double angle(cv::Point pt1, cv::Point pt2, cv::Point pt0) { double dx1 = pt1.x - pt0.x; double dy1 = pt1.y - pt0.y; double dx2 = pt2.x - pt0.x; double dy2 = pt2.y - pt0.y; return (dx1dx2 + dy1dy2)/sqrt((dx1dx1 + dy1dy1)(dx2dx2 + dy2dy2) + 1e-10); }
/** * Helper function to display text in the center of a contour */ void setLabel(cv::Mat& im, const std::string label, std::vector<cv::point>& contour) { int fontface = cv::FONT_HERSHEY_SIMPLEX; double scale = 0.4; int thickness = 1; int baseline = 0;
cv::Size text = cv::getTextSize(label, fontface, scale, thickness, &baseline);
cv::Rect r = cv::boundingRect(contour);
cv::Point pt(r.x + ((r.width - text.width) / 2), r.y + ((r.height + text.height) / 2));
cv::rectangle(im, pt + cv::Point(0, baseline), pt + cv::Point(text.width, -text.height), CV_RGB(255,255,255), CV_FILLED);
cv::putText(im, label, pt, fontface, scale, CV_RGB(0,0,0), thickness, 8);
}
int main(int argc, char** argv) { //cv::Mat src = cv::imread("polygon.png"); cv::Mat src = cv::imread(argv[1]); if (src.empty()) return -1;
// Converti in scala di grigi
cv::Mat gray;
cv::cvtColor(src, gray, CV_BGR2GRAY);
// Utilizzare Canny invece di soglia per la cattura di piazze con ombreggiatura gradiente
cv::Mat bw;
cv::Canny(gray, bw, 0, 50, 5);
// Trova contorni
std::vector<std::vector<cv::Point> > contours;
cv::findContours(bw.clone(), contours, CV_RETR_EXTERNAL, CV_CHAIN_APPROX_SIMPLE);
std::vector<cv::Point> approx;
cv::Mat dst = src.clone();
for(unsigned int l=0;l<contours.size();l++)
{
if (contours[l].size() == 4 /*&& contours[l].size() <= 6*/)
{
//cout << "# of contour points: " << contours[l].size() << endl ;
cout << endl ;
for(unsigned int k=0;k<contours[l].size();k++)
{
//cout << "Point(x,y)=" << contours[l][k] << endl;
cout << contours[l][k] << ";";
}
//cout << " Area: " << contourArea(contours[l]) << endl;
}
}
//cv::imshow("src", src);
//cv::imshow("dst", dst);
cv::waitKey(0);
return 0;
}
