Question

How can I apply a hanning window to 3D matrix ?

a = rand(10,11,12); w = hanning(10)*hanning(11)'; w3 = repmat(w,1,1,12); aw = a.*w3; Is this the correct method ?

6 mesi ago | 0 answers | 0

Question

How much should you zero pad an image before taking the fft ?

If i have an image that is 200x200 and I want to take the FFT how much zero padding is required ?

6 mesi ago | 1 answer | 0

Question

check for keyboard press in while loop

I'd like to check for a keyboard press and increment a number if the right arrow key is pressed and decrement if the left array ...

7 mesi ago | 1 answer | 0

Question

using imresize in the fourier domain

x = rand(200,200); y = imresize(x,2); v1 = fftn(y); v = fftn(x); v2 = imresize(v,1/2) ./ 2; My question is would v1 and v2 ...

8 mesi ago | 1 answer | 0

Question

Does imtranslate do subpixel shifts ?

x = randi(256,200,200); y = imtransalte(x,[-20.5 10.3]); I know that you can specify a decimal when using imtranslate, but wi...

8 mesi ago | 1 answer | 0

Question

Pad array to certain size

I would like to pad my matrix x so that the resulting size of the matrix is 425x425. How would I achieve this ? x = randi(256,...

8 mesi ago | 1 answer | 0

Question

Does fftn do post padding ?

x = randi(256, 200,200,200); x = fftn(x,[256,256,256]); Is this post padding by 56 ?

8 mesi ago | 1 answer | 0

Question

Upsampled image FFT contains NaNs.

I upsampled images and when I take the FFT I get NaN values. How can I prevent NaN values from showing when I take the fourier t...

8 mesi ago | 1 answer | 0

Question

imshow not working when going from unit8 to double

I converted an image from uint8 to double but when I use imshow on the matrix type double, it shows a white box. Why does that h...

9 mesi ago | 2 answers | 0

Question

How can I convert an image to polar coordinates ?

Hi I have attached the lena image, and I wanted to convert this image to polar coordinates. Could anyone guide me. Thanks.

9 mesi ago | 2 answers | 0

Question

How can I smooth out an image but keep the detail ?

I have an image of different exposures, and there are clear boundaries between the exposures. How could I remove the boundaries ...

10 mesi ago | 1 answer | 0

Question

How to average more than 50 3D matrices using nanmean

Hi, I am trying to average a lot of 3D matrices using NaNmean. I have tried using cat but my 3D matrices are huge (351x400x400) ...

11 mesi ago | 1 answer | 0

Question

How to make a video of two plots rather than one

I am iterating frame by frame between two different volumes of images, I want to make a video so that there is a side by side co...

11 mesi ago | 1 answer | 0

Question

change a logical array value based on the index of another matrix

I have a logical matrix the same size as matrix A. If A has a value above a threshold, I want to change the corresponding index...

11 mesi ago | 1 answer | 0

Question

Do you lose information when processing images that have been grayscaled?

I have a comple double matrix and I mat2gray the matrix for registration. Am I losing information in terms of the image ? Should...

12 mesi ago | 1 answer | 0

Question

Will imtranslate 'Fill Values' to NaN rather than an actual color ?

I want to fill values as NaN to the resulting image matrix rather than the default 0. Is this possible ?

circa un anno ago | 0 answers | 0