6、OpenCV：图像与视频处理及基本数据类型详解

OpenCV：图像与视频处理及基本数据类型详解

1. 图像像素信息查看与处理

在图像处理中，我们常常需要查看图像特定位置的像素信息。以下代码展示了如何获取图像中某点的 RGB 颜色值、灰度值以及金字塔处理后的像素值，并对 Canny 边缘检测图像的特定像素进行设置。

uchar blue  = intensity[0];
uchar green = intensity[1];
uchar red   = intensity[2];
std::cout << "At (x,y) = (" << x << ", " << y <<
          "): (blue, green, red) = (" <<
          (unsigned int)blue <<
          ", " << (unsigned int)green << ", " <<
          (unsigned int)red << ")" << std::endl;
std::cout << "Gray pixel there is: " <<
             (unsigned int)img_gry.at<uchar>(y, x) << std::endl;
x /= 4; y /= 4;
std::cout << "Pyramid2 pixel there is: " <<
             (unsigned