How do I call BLOCKPROC with more than one input image?

8 visualizzazioni (ultimi 30 giorni)
i have two images,and have a function which requires 3x3 sliding window data from both image A and image B. Is there a way to get it done with blockpro function. Any hint would be useful.

Risposte (2)

Image Analyst
Image Analyst il 8 Ott 2013
See demos attached below.
  4 Commenti
Sukuchha
Sukuchha il 15 Ott 2013
its because the result of the function depends on both 3x3 blocks of both image A and image B. I finally managed to get around with combining images like cat)3, imageA, imageB). then using blockproc with combine image. In the functin i have extracted imageA and imageB part to proceed with further processing. thx.
Image Analyst
Image Analyst il 15 Ott 2013
Sounds sort of complicated. What type of image are A and B? If they're color then you have 6 color channels on the cat'ed array, if they're grayscale, then you have 2. Usually image processing works with 1 or 3 color channels, not 2 or 6, so I'd be careful that it's doing what you expect. Why would you not do it like I said where you do it on A and then do it on B and then combine the results? That seems much more straightforward and less risky.

Accedi per commentare.


Ashish Uthama
Ashish Uthama il 10 Ott 2013
Modificato: Ashish Uthama il 10 Ott 2013
Have a look at the Definitions section of the blockproc doc. Consider using the 'location' and 'blockSize' fields to index into the second variable.
>> im1 = ones(10);
>> im2 = ones(10)*2;
>> type myfun.m
function o = myfun(bs, im2)
im1Block = bs.data;
startInd = bs.location;
endInd = bs.location+bs.blockSize-1;
im2Block = im2(startInd(1):endInd(1), startInd(2):endInd(2));
o = im1Block+im2Block;
end
% This is the tricky part. Here, all of im2 gets 'snapshot'ed inthe function handle, so its available inside myfun when called via funcHandle inside blockproc (!).
>> funcHandle = @(bs)myfun(bs,im2);
>> blockproc(im1,[5 5],funcHandle)
ans =
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
3 3 3 3 3 3 3 3 3 3
>>
  1 Commento
Sukuchha
Sukuchha il 15 Ott 2013
hi , i never knew ther is location properties. cheers. But i just combine mz images and extract part of imageA and imageB in my function handle for blockproc. thx.

Accedi per commentare.

Community Treasure Hunt

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

Start Hunting!

Translated by