【OpenCV】图像的载入显示和输出示例程序.rar_源码

#include <vector> #include <stdio.h> #include<opencv2/opencv.hpp> using namespace cv; using namespace std; void createAlphaMat(Mat &mat) { for(int i = 0; i < mat.rows; ++i) { for(int j = 0; j < mat.cols; ++j) { Vec4b&rgba = mat.at<Vec4b>(i, j); rgba[0]= UCHAR_MAX; rgba[1]= saturate_cast<uchar>((float (mat.cols - j)) / ((float)mat.cols) *UCHAR_MAX); rgba[2]= saturate_cast<uchar>((float (mat.rows - i)) / ((float)mat.rows) *UCHAR_MAX); rgba[3]= saturate_cast<uchar>(0.5 * (rgba[1] + rgba[2])); } } } int main( ) { //创建带alpha通道的Mat Mat mat(480, 640, CV_8UC4); createAlphaMat(mat); vector<int>compression_params; compression_params.push_back(CV_IMWRITE_PNG_COMPRESSION); compression_params.push_back(9); try{ imwrite("透明Alpha值图.png", mat, compression_params); } catch(runtime_error& ex) { fprintf(stderr,"图像转换成PNG格式发生错误：%s\n", ex.what()); return 1; } fprintf(stdout,"PNG图片文件的alpha数据保存完毕~\n"); return 0; }