opencv_07之調整影象亮度和對比度
阿新 • • 發佈:2018-12-15
#include <opencv2/opencv.hpp> #include <iostream> using namespace std; using namespace cv; int main(int argc, char** argv) { Mat src, dst; src = imread("C:/Users/liyangxian/Desktop/bjl/nm2.jpg"); if (!src.data) { printf("no load..\n"); return -1; } char input_win[] = "input image"; //cvtColor(src, src, CV_BGR2GRAY);//轉換為單通道的灰度影象 namedWindow(input_win, CV_WINDOW_AUTOSIZE); imshow(input_win, src); //獲取行列 int height = src.rows; int width = src.cols; dst = Mat::zeros(src.size(), src.type()); float alpha = 1.5;//對比度 float beta = 10;//亮度 //改變對比度和亮度 //Mat m1;//將影象轉換成3位float型別 //src.convertTo(m1, CV_32F); for (int row = 0; row < height; row++) { for (int col = 0; col < width; col++) { if (src.channels() == 3) { //獲取每個畫素的b\g\r float b = src.at<Vec3b>(row, col)[0];//blue float g = src.at<Vec3b>(row, col)[1];//green float r = src.at<Vec3b>(row, col)[2];//red /*//裝換成32位以後,對其進行操作 float b = src.at<Vec3f>(row, col)[0]; float g = src.at<Vec3f>(row, col)[1]; float r = src.at<Vec3f>(row, col)[2]; */ //調節畫素的值 dst.at<Vec3b>(row, col)[0] = saturate_cast<uchar>(b*alpha + beta); dst.at<Vec3b>(row, col)[1] = saturate_cast<uchar>(g*alpha + beta); dst.at<Vec3b>(row, col)[2] = saturate_cast<uchar>(r*alpha + beta); } else if (src.channels() == 1) { float v = src.at<uchar>(row, col); dst.at<uchar>(row, col) = saturate_cast<uchar>(v*alpha + beta); } } } char output_win[] = "contrast and brightness change demo"; namedWindow(output_win, CV_WINDOW_AUTOSIZE); imshow(output_win, dst); waitKey(0); return 0; }