引言

高斯金字塔

向下取样

 向下取样也就是缩小图像

向上取样

向上取样也就是放大图像 

拉普拉斯金字塔

尺寸调整:resize()函数

 resize调用例程

#include <iostream>
#include <opencv2/core.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/video.hpp>
 
using namespace cv;
using namespace std;

int main(int argc, char** argv)
{
	Mat dstImage = Mat::zeros(512, 512, CV_8UC3);//新建一张512*512尺寸的图片
	Mat srcImage = imread("700levi.jpg");
	//显示指定dsize=dstImage.size(), 那么fx和fy会被计算出来, 不用额外指定
	resize(srcImage, dstImage, dstImage.size());
	imshow("原图", srcImage);
	imshow("效果图", dstImage);
	waitKey(0);
	return 0;
}

#include <iostream>
#include <opencv2/core.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/video.hpp>
 
using namespace cv;
using namespace std;

int main(int argc, char** argv)
{
	Mat srcImage = imread("700levi.jpg");
	Mat tempImage, dstImage1, dstImage2;
	tempImage = srcImage;
	imshow("原图", srcImage);
	resize(tempImage, dstImage1, Size(tempImage.cols / 2, tempImage.rows / 2), (0, 0), (0, 0), 3);
	resize(tempImage, dstImage2, Size(tempImage.cols * 2, tempImage.rows * 2), 0, 0, 3);
	imshow("效果图1", dstImage1);
	imshow("效果图2", dstImage2);

	waitKey(0);
	return 0;
}

 效果图

 图像金字塔相关API

pyrUp()

 例程

#include <iostream>
#include <opencv2/core.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/video.hpp>
 
using namespace cv;
using namespace std;

int main(int argc, char** argv)
{
	Mat srcImage = imread("700levi.jpg");
	imshow("原始图", srcImage);

	Mat tempImage, dstImage;
	tempImage = srcImage;
	pyrUp(tempImage, dstImage, Size(tempImage.cols * 2, tempImage.rows * 2));
	imshow("效果图", dstImage);

	waitKey(0);
	return 0;
}

效果

 pyrDown()

例程

#include <iostream>
#include <opencv2/core.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/video.hpp>
 
using namespace cv;
using namespace std;

int main(int argc, char** argv)
{
	Mat srcImage = imread("700levi.jpg");
	imshow("原始图", srcImage);

	Mat tempImage, dstImage;
	tempImage = srcImage;
	pyrDown(tempImage, dstImage, Size(tempImage.cols / 2, tempImage.rows / 2));
	imshow("效果图", dstImage);

	waitKey(0);
	return 0;
}

 效果