i can't uderstand the image blurring in following code....what does the following blurring filter do? how does it work?

3 次查看（过去 30 天）
shawn
shawn 2012-7-19
i read the following code for a filter that blurs and then deblurs the image but the resultant blurring image is not expected... can you please explain why is it so? even though the deblurred result actually looks like the blurred expectation....
iBlur = Blurred result
iRes = restored
function h = generateFilter(s,img)
h = [];
[width,height] = size(img);
for y = 1:height
for x = 1:width
h(x,y) = (s/(2*pi))^(-s*sqrt(x^2+y^2));
end
end
% 'h' is the bluring filter
h = h / sum(sum(h)); % normalize
end
function [iRes,h] = applyBlurFilter(s,img);
iRes = [];
h = generateFilter(s,img);
H = fft2(h);
IMG = fft2(img);
I_BLUR = IMG .* H;
figure; imshow(uint8(I_BLUR));
iRes = ifft2(I_BLUR);
figure; imshow(uint8(iRes));
end
a =imread(filename);
a = rgb2gray(a);
s = 0.2 % the value of s can be ranged from 0.1-0.5 to observe any sort of output....
applyBlurFilter(s,a)
please help...

请先登录，再回答此问题。

回答（2 个）

Ryan
Ryan 2012-7-20
编辑：Ryan 2012-7-20
I believe your unblurred is your expected blurred, and your blurred is actually the frequency domain for the blurred image. The filter is a Gaussian of some sort, I think it's an averaging filter due to the division by the sum(sum()).
Element wise division in the frequency domain with H will deblur it.
Image Analyst
Image Analyst 2012-7-20
All you do is inverse FFT your blurred image, so of course it looks blurred back in the spatial domain. If you didn't want that you'd have to do an "inverse filter" by dividing your fourier domain image by H before you IFFT it.

类别

在 Help Center 和 File Exchange 中查找有关 Deblurring 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by