怎样利用matlab调整图像，让图像暗处变亮，亮出尽量不变

street1=imread('street1.jpg')% Load image data

street2=imread('street2.jpg')

whos street1 street2

%%

% Here we see the images are 24-bit color, stored as three planes of |uint8| data.

%% Display images

% Display first image.

cla

image(street1)% Display image

axis equalaxis off

%%

% Display second image

image(street2)% Display image

axis equalaxis off

%% Scale an image

% We can scale the image by a double precision constant but keep the image

% stored as integers. For example,

duller = 0.5 * street2% Scale image with a double constant but create an integer

whos duller

%%

subplot(1,2,1)

image(street2)

axis off equal tight

title('Original') % Display image

subplot(1,2,2)

image(duller)

axis off equal tight

title('Duller') % Display image

%% Add the images

% We can add the two street images together and plot the ghostly result.

combined = street1 + duller% Add |uint8| images

subplot(1,1,1)

cla

image(combined)% Display image

title('Combined')

axis equalaxis off

这是matlab帮助文件中的，，可以把图像叠前扒埋加，同理是否可以把图片数据进此历行筛选，比如小于一定值慧蚂的数据将其加上固定值？？

% 读取图像A

A = imread('rice.png')

% 读取图衡滑升像B

B = imread('cameraman.tif')

%两图像相减

C=B-A

%显示三幅图像咐老让敏

figure

imshow(A)

figure

imshow(B)

figure

imshow(uint8(C))

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