1.编写程序，完成灰度分段线性变换。如下图所示，输入两个点的坐标完成对图像的分段线性对比度拉伸。







2. 学习使用histeq函数，完成

①对’lena.bmp‘的直方图均衡化；

②以’cameraman.tif’的直方图为模板，将’lena.bmp’做直方图匹配。

3. 不使用histeq函数，自己编写程序完成直方图均衡化，并显示直方图均衡化前后的图像以及其直方图。

4. 不使用histeq函数，自己编写程序完成直方图匹配，显示匹配前后的图像、模板直方图和匹配过的直方图。

-1. Write a program to complete the gray piecewise linear transformation. As shown below, enter the coordinates of two points to complete the piecewise linear contrast of the image stretched. 2. Learn to use histeq function, complete ① on ' lena.bmp'　histogram equalization　② to ' cameraman.tif'　histogram as a template, the ' lena.bmp'　do histogram matching. 3. Do not use histeq function, write your own program to complete histogram equalization, and display the image and its histogram before and after histogram equalization. 4. Do not use histeq function, write your own program to complete histogram matching, display images before and after the match, the template histogram and histogram matching too.