Answered
How to find the "true" perimeter of objects in a binary image?
One possible way is like this: % Example binary image with 3 non-zero pixels img = false(5); % Use zeros(5) if you pref...

10 years ago | 0

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Answered
Please help me to convert opencv matrix multiplication into matlab
Your code is fine, it's just rounding error. Note that the differences are smaller, by many orders of magnitude, than the larges...

10 years ago | 0

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Answered
Matrix Dimensions Must Agree Error, Error using +
It's necessary to put spaces in the expression for |f| so that |+| and |-| are interpreted as binary operators rather than unary...

10 years ago | 0

Submitted

Sinkhorn-Knopp algorithm for matrix normalisation
Normalises a matrix so that the row and column sums are all unity

10 years ago | 2 downloads |

4.0 / 5

10 years ago | 0

Answered
Adding constant if the pixel intensity is greater than 50?
Assuming your image is stored in a variable called |img|: highValues = img > 50; img(highValues) = img(highValues) + 200...

10 years ago | 0

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Answered
How do I get a median filtered image?
If you have the Image Processing Toolbox, you can use <http://uk.mathworks.com/help/images/ref/medfilt2.html medfilt2>.

10 years ago | 1

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which one is faster? defining a variable as a global variable or as an input of function?
It is usually a bad idea to use global variables. There are many papers, going back over 40 years or more, explaining why. One e...

10 years ago | 2

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Creating discrete variables within a for loop
I'm not quite sure what you want to do, but it feels like <http://uk.mathworks.com/help/matlab/cell-arrays.html cell arrays> mig...

10 years ago | 0

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How to run mex files in MATLAB?
I've found <http://uk.mathworks.com/help/matlab/matlab_external/introducing-mex-files.html this documentation> to be very helpfu...

10 years ago | 0

Answered
rounding problem after decimal point in image processing
If you convert to class uint8 you lose everything after the decimal point. Is that perhaps the problem? If so, don't cast to uin...

10 years ago | 0

Answered
How to extract 24 binary images from one RGB image which is of 24-bit/pixel color depth?
Try this: % example rgb 24-bit image img = imread('peppers.png'); % Make the binary array array corresponding to ea...

10 years ago | 0

Answered
Why does translation with imwarp + affine2d-object enlarges the object?
The reason for the enlargement is the interpolation rule that |imwarp| uses - 'linear' by default. Because the image is binary, ...

10 years ago | 0

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Answered
Ignoring empty arrays when using arrayfun on a structure?
Try this (not yet tested): west_east = arrayfun(@(d) ~isempty(d.TTA) && 110 >= d.TTA(1) && d.TTA(1) >= 70, data); data =...

10 years ago | 0

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Answered
How the following code works in image denoising?
To understand this properly, I think you may need to consult the author of the <http://www.mathworks.com/matlabcentral/fileexcha...

10 years ago | 0

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Answered
How can I convert back correctly a 2D matrix to 3D one?
First, the resulting array *will* be the same as the original. Here's a demonstration (making the arrays rather smaller to avoid...

10 years ago | 0

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Saving structures from each iteration into a structure? Good idea? How?
Not sure what you've tried already and had problems with, but I'd have thought it was as simple as putting the results into stru...

10 years ago | 0

Answered
How to compare the intensity of the central pixel with its 8 neighboring pixel in an image? Can anyone help me with its matlab code? Also I have to save my central pixel if its intensity value is greater than other pixels.
Some of the answers <http://uk.mathworks.com/matlabcentral/newsreader/view_thread/266606 here> should help.

10 years ago | 0

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Answered
Gaussian and Laplacian Random Variables
You can generate random values from a Gaussian distribution with the |randn| function. This <https://en.wikipedia.org/wiki/Lapla...

10 years ago | 0

Answered
How to use a while loop with irregular step?
You can do it with a |for| loop very simply: for i = [1,2,3, 5,7,9, 12,15,18] % < process using i > end By the w...

10 years ago | 0

Answered
Perform conv2 on a batch of images
|convn| does exactly what you describe, given a 3-D array and a 2-D kernel.

10 years ago | 1

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Answered
Is it possible to create a histogram with fractional entries for each bin?
If all the samples are positive integers, and the bins are all centred on the positive integers and with unit width, as in the i...

10 years ago | 0

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Answered
Can anybody help with persistant errors? (Matlab beginer)
The assignment to |wPtr| in the first line of the function has been commented out. This means that no value has been given to th...

10 years ago | 0

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Answered
How to interpolate and leave NaNs if long gaps?
I'd adopt a slightly different approach. I'd quantize the times first to get an array of just the times you want, then interpola...

10 years ago | 2

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Answered
Can a function which works well for grayscale images be applied for RGB images also?
In general, yes. You can either apply it to each of the R, G and B planes in turn, and then recombine the results, or you may be...

10 years ago | 0

Answered
Question about the image resampling
It's just, I think, because we are told near the start of the article: _An important factor is that the sampling intervals ar...

10 years ago | 0

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Answered
Gray(scale) image with a colormap - how to turn into double?
This works OK: [imInd, cmap] = imread('10.bmp'); imGrayUint8 = ind2gray(imInd, cmap); imGrayDouble = im2double(imGray...

10 years ago | 0

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Answered
accessing indexed values in a 3D array
[rows, cols] = ndgrid(1:size(Z,1), 1:size(Z,2)); Zindex = sub2ind(size(Z), rows, cols, ind); s = Z(Zindex);

10 years ago | 2

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Answered
How can I use 'impixelinfo' function?
Perhaps you don't have the Image Processing Toolbox (IPT), or perhaps you have a very old version (before R14). Give the command...

10 years ago | 0

Answered
How can I assign a value to a variable in the first iteration of a loop and for the rest of iterations the variable's value should be the outcome of the script?
Make y an argument to your function, and also remove unnecessary code: function y = fcn(v, u, y) y = y+(u-v); end ...

10 years ago | 1