#include <iostream> #include <string> #include <list> #include <vector> #include <map> #include <stack> #include <opencv2/imgproc/imgproc.hpp> #include <opencv2/highgui/highgui.hpp> void icvprCcaByTwoPass(const cv::Mat& _binImg, cv::Mat& _lableImg) { // connected component analysis (4-component) // use two-pass algorithm // 1. first pass: label each foreground pixel with a label // 2. second pass: visit each labeled pixel and merge neighbor labels // // foreground pixel: _binImg(x,y) = 1 // background pixel: _binImg(x,y) = 0 if (_binImg.empty() || _binImg.type() != CV_8UC1) { return ; } // 1. first pass _lableImg.release() ; _binImg.convertTo(_lableImg, CV_32SC1) ; int label = 1 ; // start by 2 std::vector<int> labelSet ; labelSet.push_back(0) ; // background: 0 labelSet.push_back(1) ; // foreground: 1 int rows = _binImg.rows - 1 ; int cols = _binImg.cols - 1 ; for (int i = 1; i < rows; i++) { int* data_preRow = _lableImg.ptr<int>(i-1) ; int* data_curRow = _lableImg.ptr<int>(i) ; for (int j = 1; j < cols; j++) { if (data_curRow[j] == 1) { std::vector<int> neighborLabels ; neighborLabels.reserve(2) ; int leftPixel = data_curRow[j-1] ; int upPixel = data_preRow[j] ; if ( leftPixel > 1) { neighborLabels.push_back(leftPixel) ; } if (upPixel > 1) { neighborLabels.push_back(upPixel) ; } if (neighborLabels.empty()) { labelSet.push_back(++label) ; // assign to a new label data_curRow[j] = label ; labelSet[label] = label ; } else { std::sort(neighborLabels.begin(), neighborLabels.end()) ; int smallestLabel = neighborLabels[0] ; data_curRow[j] = smallestLabel ; // save equivalence for (size_t k = 1; k < neighborLabels.size(); k++) { int tempLabel = neighborLabels[k] ; int& oldSmallestLabel = labelSet[tempLabel] ; if (oldSmallestLabel > smallestLabel) { labelSet[oldSmallestLabel] = smallestLabel ; oldSmallestLabel = smallestLabel ; } else if (oldSmallestLabel < smallestLabel) { labelSet[smallestLabel] = oldSmallestLabel ; } } } } } } // update equivalent labels // assigned with the smallest label in each equivalent label set for (size_t i = 2; i < labelSet.size(); i++) { int curLabel = labelSet[i] ; int preLabel = labelSet[curLabel] ; while (preLabel != curLabel) { curLabel = preLabel ; preLabel = labelSet[preLabel] ; } labelSet[i] = curLabel ; } // 2. second pass for (int i = 0; i < rows; i++) { int* data = _lableImg.ptr<int>(i) ; for (int j = 0; j < cols; j++) { int& pixelLabel = data[j] ; pixelLabel = labelSet[pixelLabel] ; } } } cv::Scalar icvprGetRandomColor() { uchar r = 255 * (rand()/(1.0 + RAND_MAX)); uchar g = 255 * (rand()/(1.0 + RAND_MAX)); uchar b = 255 * (rand()/(1.0 + RAND_MAX)); return cv::Scalar(b,g,r) ; } void icvprLabelColor(const cv::Mat& _labelImg, cv::Mat& _colorLabelImg) { if (_labelImg.empty() || _labelImg.type() != CV_32SC1) { return ; } std::map<int, cv::Scalar> colors ; int rows = _labelImg.rows ; int cols = _labelImg.cols ; _colorLabelImg.release() ; _colorLabelImg.create(rows, cols, CV_8UC3) ; _colorLabelImg = cv::Scalar::all(0) ; for (int i = 0; i < rows; i++) { const int* data_src = (int*)_labelImg.ptr<int>(i) ; uchar* data_dst = _colorLabelImg.ptr<uchar>(i) ; for (int j = 0; j < cols; j++) { int pixelValue = data_src[j] ; if (pixelValue > 1) { if (colors.count(pixelValue) <= 0) { colors[pixelValue] = icvprGetRandomColor() ; } cv::Scalar color = colors[pixelValue] ; *data_dst++ = color[0] ; *data_dst++ = color[1] ; *data_dst++ = color[2] ; } else { data_dst++ ; data_dst++ ; data_dst++ ; } } } } int main(int argc, char** argv) { IplImage* img1 = cvLoadImage("E:\newocr\ocr\test.jpg", 1); cv::Mat binImage(img1); //cv::Mat binImage = cv::imread("E:\newocr\ocr\test.jpg", 0) ; cv::threshold(binImage, binImage, 50, 1, CV_THRESH_BINARY_INV) ; cv::imshow("labelImg", binImage) ; // connected component labeling cv::Mat labelImg ; icvprCcaByTwoPass(binImage, labelImg) ; //icvprCcaBySeedFill(binImage, labelImg) ; // show result cv::Mat grayImg ; labelImg *= 10 ; labelImg.convertTo(grayImg, CV_8UC1) ; cv::imshow("labelImg", grayImg) ; cv::Mat colorLabelImg ; icvprLabelColor(labelImg, colorLabelImg) ; cv::imshow("colorImg", colorLabelImg) ; cv::waitKey(0) ; return 0 ; }
连通区域
时间: 2024-10-10 09:08:34