Analysing frequency components
显示 更早的评论
Hi,
which frequency components are responsible for texture in an image?
I heard lot of people saying high frequency components are resposible for texture in an image
But how?
I cannot find anything except complex values and spectrum by using fft2 command
How this can be analysed from the fft
Can anybody suggest something about this?
Thanks in advance
回答（2 个）
Walter Roberson
2012-5-23
Why don't you construct an artificial image and start playing?
bar = zeros(64,64,'uint8');
bar(:) = 128;
bar(:,10:10:end) = 255;
bar(10:10:end,:) = 255;
colormap(gray(256));
imagesc(bar);
Now you can start exploring the fft() and fft2() properties with a "best-case" image.
foo = fft2(bar);
DC = foo(1,1);
foo(1,1) = 0;
imagesc(real(foo));
What do you see? Can you explain why?
Image Analyst
2012-5-23
0 个投票
Yeah but that lot of people may not know what they're talking about, or you may have oversimplified what they said. We talked about this before, remember? Remember when I explained how periodic texture will show up as periodic patterns (i.e. spikes) in the spectrum. Walter's suggestion of playing around with different images to see their spectrum is a good one.
类别
在 帮助中心 和 File Exchange 中查找有关 Timing and presenting 2D and 3D stimuli 的更多信息
产品
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
