计算机图像处理实验四：图像对比度调整（MATLAB）

我就是我 2021-09-08 07:08 552阅读 0赞

> **【实验名称】**
> 
> 图像对比度调整

> **【实验目的】**
> 
> 1.  通过本次实验掌握图像对比度自动调整技术；
> 2.  .熟悉使用库函数imhist、histeq；
>     
>

> ** 【实验内容】**
> 
> 1.  利用库函数imhist计算并分别显示下图（图1）中图像的直方图，并分析图像质量；
> 2.  利用熟悉的图像处理技术对以上图像进行图像处理，比对效果，最后推荐一种方法。
> 
> ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70][]

> ** 【实验代码】**
> 
> 显示各个图像以及直方图（subplot形式显示）
> 
>     clc;clear;close all;
>     img1=imread('实验4_Fig1.tif');
>     img2=imread('实验4_Fig2.jpg');
>     img3=imread('实验4_Fig3.jpg');
>     % 图1
>     subplot(2,3,1);
>     imshow(img1);
>     subplot(2,3,4);
>     imhist(img1);
>     % 图2
>     subplot(2,3,2);
>     imshow(img2);
>     subplot(2,3,5);
>     imhist(img2);
>     % 图3
>     subplot(2,3,3);
>     imshow(img3);
>     subplot(2,3,6);
>     imhist(img3);
> 
> 线性插值处理：
> 
>     clc;clear;close all;
>     % 线性插值
>     img1=imread('实验4_Fig3.jpg');
>     [m,n,k]=size(img1);
>     a=double(img1);
>     amin=0;
>     amax=255;
>     alow=min(a(:));
>     ahigh=max(a(:));
>     a2=amin+(a-alow)*(amax-amin)/(ahigh-alow);
>     img2=uint8(a2);
>     subplot(2,2,1)
>     imshow(img1)
>     title('原图')
>     subplot(2,2,2)
>     imshow(img2)
>     title('自动调整后')
>     subplot(2,2,3)
>     imhist(img1)
>     subplot(2,2,4);
>     imhist(img2)
> 
> 非线性变换处理（对数变换）
> 
>     clc;clear;close all;
>      I=imread('实验4_Fig2.jpg');             
>      subplot(1,2,1),imshow(I);
>      title(' 原图像');
>      axis([50,250,50,200]);                
>      J=double(I);
>      J=40*(log(J+1));
>      H=uint8(J);
>      subplot(1,2,2),imshow(H);
>      title(' 非线性变换--对数变换图像');
>      axis([50,250,50,200]);
> 
> 直方图等值化处理
> 
>     clc;
>     clear;
>     close all;
>     img1=imread('实验4_Fig1.tif');
>     subplot(1,2,1);
>     imshow(img1);
>     title('原图像');
>     img2=histeq(img1);
>     subplot(1,2,2);
>     imshow(img2);
>     title('直方图等值化后图像');

> **【运行结果】**
> 
> 分别显示三个图像以及对应的直方图（subplot形式显示）
> 
> ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 1][]
> 
> 线性插值:
> 
> ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 2][]
> 
>  ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 3][]
> 
> ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 4][]
> 
> 非线性变换之对数变换
> 
> ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 5][]
> 
>  ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 6][]
> 
>  ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 7][]
> 
>  直方图等值化
> 
> ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 8][]
> 
>  ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 9][]
> 
>  ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDEwNzE0MA_size_16_color_FFFFFF_t_70 10][]

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