25,386 total contributions since 2008

Senior Scientist in one of the world's 10 largest industrial corporations doing image analysis full time. Ph.D. in Optical Sciences specializing in imaging, image processing, and image analysis. 37+ years of military, academic, and (mostly) industrial experience with image analysis programming and algorithm development. Experience designing custom light booths and other imaging systems. Experience with color and monochrome imaging, video analysis, thermal, ultraviolet, hyperspectral, CT, MRI, radiography, profilometry, microscopy, NIR and Raman spectroscopy, etc. on a huge variety of subjects. Be sure to click "View All" in my File Exchange to see ALL of my demos and tutorials: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862

Professional Interests: Image analysis and processing

Answered

Find double repetitions in a (sorted) array.

If you have the Image Processing Toolbox, you can use regionprops(): % Assignment of a struct with a field containing integ...

Find double repetitions in a (sorted) array.

If you have the Image Processing Toolbox, you can use regionprops(): % Assignment of a struct with a field containing integ...

9 hours ago | 0

Answered

Projection matrix equation equivalent?

To reproduce in C you'd need for loops. I believe this explains it: B = rand(10,3); i = 4; % Whatever.... % Method 1...

Projection matrix equation equivalent?

To reproduce in C you'd need for loops. I believe this explains it: B = rand(10,3); i = 4; % Whatever.... % Method 1...

9 hours ago | 0

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Answered

How to remove pictoral muscle and other artifacts from breast color image not grayscale image

You can segment the image to find the parts you want to mask out. Then do this: % Mask the image using bsxfun() function to...

How to remove pictoral muscle and other artifacts from breast color image not grayscale image

You can segment the image to find the parts you want to mask out. Then do this: % Mask the image using bsxfun() function to...

10 hours ago | 0

Answered

How to plot the exponentional function in matlab

You need to use the plot() function.

How to plot the exponentional function in matlab

You need to use the plot() function.

12 hours ago | 0

Answered

How can iI stretch my image histogram?

Try stretchlim(). See my answer to someone else for code: <https://www.mathworks.com/matlabcentral/answers/362425-how-would-i-i...

How can iI stretch my image histogram?

Try stretchlim(). See my answer to someone else for code: <https://www.mathworks.com/matlabcentral/answers/362425-how-would-i-i...

12 hours ago | 0

Answered

how to determine n lowest value of an array and display it on a table.

Sort them then take the lowest 10 %templatefiles = dir('*.m') %hammingdist = randi(1000, length(templatefiles), 1) ...

how to determine n lowest value of an array and display it on a table.

Sort them then take the lowest 10 %templatefiles = dir('*.m') %hammingdist = randi(1000, length(templatefiles), 1) ...

12 hours ago | 0

Answered

Wait for a condition to be met...

Try putting it in a while loop: nIn = 3; numPoints = 0; instructions = sprintf('Please click on exactly %d points', n...

Wait for a condition to be met...

Try putting it in a while loop: nIn = 3; numPoints = 0; instructions = sprintf('Please click on exactly %d points', n...

13 hours ago | 1

| accepted

Answered

Save bode diag as an image

Use export_fig. See the FAQ <http://matlab.wikia.com/wiki/FAQ#How_do_I_save_my_figure.2C_axes.2C_or_image.3F_I.27m_having_troub...

Save bode diag as an image

Use export_fig. See the FAQ <http://matlab.wikia.com/wiki/FAQ#How_do_I_save_my_figure.2C_axes.2C_or_image.3F_I.27m_having_troub...

24 hours ago | 0

Answered

Help For Engineering plotting

Figure out fuel flow rate and angular speed from your equations. Then use plot(): fuelFlowRate = ....... % Q angularSpe...

Help For Engineering plotting

Figure out fuel flow rate and angular speed from your equations. Then use plot(): fuelFlowRate = ....... % Q angularSpe...

1 day ago | 0

Answered

How would i implement contrast stretching that will have 5% of lowest and highest pixel values to be excluded? I know i have to use histogram and cdf to check the intensities but how would i do it without using matlab functions?

Try this: clc; % Clear command window. clear; % Delete all variables. close all; % Close all figure windows except th...

How would i implement contrast stretching that will have 5% of lowest and highest pixel values to be excluded? I know i have to use histogram and cdf to check the intensities but how would i do it without using matlab functions?

Try this: clc; % Clear command window. clear; % Delete all variables. close all; % Close all figure windows except th...

1 day ago | 0

Answered

Merge two data sets/matrices from different sources

You can use readtable() and innerjoin() or outerjoin(). You forgot to attach the files so that's about all I can suggest.

Merge two data sets/matrices from different sources

You can use readtable() and innerjoin() or outerjoin(). You forgot to attach the files so that's about all I can suggest.

1 day ago | 0

Answered

How would i implement contrast stretching that will have 5% of lowest and highest pixel values to be excluded? I know i have to use histogram and cdf to check the intensities but how would i do it without using matlab functions?

Use stretchlim(): Low_High = stretchlim(I,Tol) returns Low_High, a two-element vector of pixel values that specify lower and ...

How would i implement contrast stretching that will have 5% of lowest and highest pixel values to be excluded? I know i have to use histogram and cdf to check the intensities but how would i do it without using matlab functions?

Use stretchlim(): Low_High = stretchlim(I,Tol) returns Low_High, a two-element vector of pixel values that specify lower and ...

1 day ago | 0

Answered

Find double repetitions in a (sorted) array.

You didn't tag it as homework. Is it? This will do it: % Assignment of a struct with a field containing integer numbers ...

Find double repetitions in a (sorted) array.

You didn't tag it as homework. Is it? This will do it: % Assignment of a struct with a field containing integer numbers ...

1 day ago | 0

Answered

Skin segmentation/ Skin detection

Try the Color Thresholder on the Apps tab of the tool ribbon. Also, see my attached skin detection demo.

Skin segmentation/ Skin detection

Try the Color Thresholder on the Apps tab of the tool ribbon. Also, see my attached skin detection demo.

1 day ago | 0

Answered

How to find local minima in a image histogram?

Use diff() to get the difference between the n+1st bin and the nth bin. Then use find to get the index [counts, grayLevels...

How to find local minima in a image histogram?

Use diff() to get the difference between the n+1st bin and the nth bin. Then use find to get the index [counts, grayLevels...

2 days ago | 0

Answered

Hi guys, I am working on Barrel distortion correction using MATLAB. I have written code as per correction algorithm. I am unable to mathematically compare corrected output with original image can you suggest me some parameter for it..

Formulas for correction are given here: <https://en.wikipedia.org/wiki/Distortion_(optics)#Software_correction>

Hi guys, I am working on Barrel distortion correction using MATLAB. I have written code as per correction algorithm. I am unable to mathematically compare corrected output with original image can you suggest me some parameter for it..

Formulas for correction are given here: <https://en.wikipedia.org/wiki/Distortion_(optics)#Software_correction>

2 days ago | 0

Answered

Different answer using inbuilt function and own code for entropy

Simply edit entropy.m and you'll see _*exactly*_ how they do it: % calculate histogram counts p = imhist(I(:)); %...

Different answer using inbuilt function and own code for entropy

Simply edit entropy.m and you'll see _*exactly*_ how they do it: % calculate histogram counts p = imhist(I(:)); %...

2 days ago | 0

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Answered

log-scaled histogram intersection

That code will only tell you if the histograms are similar, not if the images are similar. You could take your image and rearra...

log-scaled histogram intersection

That code will only tell you if the histograms are similar, not if the images are similar. You could take your image and rearra...

2 days ago | 0

Answered

how to calculate the entropy of an image?

Post your image where you get zero. If it's a uint8 image, try casting to double() before sending it into entropy().

how to calculate the entropy of an image?

Post your image where you get zero. If it's a uint8 image, try casting to double() before sending it into entropy().

2 days ago | 1

| accepted

Answered

Loop through hundreds of matrices to change values larger than 1 to 0

If you want a *_loop_* and your images are in the *cell array*, you can do it like this: for k = 1 : length(images) % E...

Loop through hundreds of matrices to change values larger than 1 to 0

If you want a *_loop_* and your images are in the *cell array*, you can do it like this: for k = 1 : length(images) % E...

2 days ago | 1

| accepted

Answered

Can I extract brown lines from one image?

Try this: % Extract the individual red, green, and blue color channels. redChannel = rgbImage(:, :, 1); greenChannel = rg...

Can I extract brown lines from one image?

Try this: % Extract the individual red, green, and blue color channels. redChannel = rgbImage(:, :, 1); greenChannel = rg...

3 days ago | 1

| accepted

Answered

I wonder how rgb data are inserted in matlab

Of course. Any given color plane (channel) is just a 2-D array of numbers, just like a gray scale image. If you want, you can ...

I wonder how rgb data are inserted in matlab

Of course. Any given color plane (channel) is just a 2-D array of numbers, just like a gray scale image. If you want, you can ...

3 days ago | 0

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Answered

Resizing an image that is half as large in both height and width without imresize

Try this: kernel = ones(2)/4; out = conv(double(grayImage), kernel, 'same'); out = out(1:2:end, 1:2:end);

Resizing an image that is half as large in both height and width without imresize

Try this: kernel = ones(2)/4; out = conv(double(grayImage), kernel, 'same'); out = out(1:2:end, 1:2:end);

3 days ago | 0

Answered

How do I resize an irregular matrix?

Try this: A = [3,1,4,1,3,6,9,3,1,3] [~, indexOfMax] = max(A); B = A(indexOfMax:end)

How do I resize an irregular matrix?

Try this: A = [3,1,4,1,3,6,9,3,1,3] [~, indexOfMax] = max(A); B = A(indexOfMax:end)

3 days ago | 0

Answered

Can I make bwareafilt keep any ties for n-th place?

Please post your binary image where this happens. Also state the criteria where you'd delete one. For example, if you take the...

Can I make bwareafilt keep any ties for n-th place?

Please post your binary image where this happens. Also state the criteria where you'd delete one. For example, if you take the...

3 days ago | 1

| accepted

Answered

noise removal from the part of the medical image where noise is actually present, not the whole image

I agree with Bjorn - the radiologist will be able to mentally filter out the noisy areas. If you still want to do it for some...

noise removal from the part of the medical image where noise is actually present, not the whole image

I agree with Bjorn - the radiologist will be able to mentally filter out the noisy areas. If you still want to do it for some...

3 days ago | 0

Answered

i'm trying to pixelated image using nested for loops what wrong here?regardless it's in comments

Two more things wrong, other than what Matt said # All lines are commented out # The size call is wrong for a color image. ...

i'm trying to pixelated image using nested for loops what wrong here?regardless it's in comments

Two more things wrong, other than what Matt said # All lines are commented out # The size call is wrong for a color image. ...

4 days ago | 0

Answered

How to extract contour line from my image

Why? What's the "use case"? All I can suggest is bwselect() but your contour lines are very very broken so you may just get ...

How to extract contour line from my image

Why? What's the "use case"? All I can suggest is bwselect() but your contour lines are very very broken so you may just get ...

4 days ago | 0

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Answered

Hi everyone, Can I have some help plotting a projectile motion graph of x vs. y?

Sorry, I have no time tonight to go over your code, but I'm attaching my projectile demo that calculates and plots virtually any...

Hi everyone, Can I have some help plotting a projectile motion graph of x vs. y?

Sorry, I have no time tonight to go over your code, but I'm attaching my projectile demo that calculates and plots virtually any...

4 days ago | 0

| accepted