25,696 total contributions since 2010

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

how can i plot 5 periods of this signal

Perhaps you mean this: samples = 500; T = 5; % Period f0 = 1/T; % Not used! t = linspace(0, T, samples); % 5 cycle...

how can i plot 5 periods of this signal

Perhaps you mean this: samples = 500; T = 5; % Period f0 = 1/T; % Not used! t = linspace(0, T, samples); % 5 cycle...

8 hours ago | 0

Answered

how can i plot 5 periods of this signal

Your linspace() is wrong. You could do this: samples = 500; T = 5; % Period f0 = 1/T; % Not used! t = linspace(0,...

how can i plot 5 periods of this signal

Your linspace() is wrong. You could do this: samples = 500; T = 5; % Period f0 = 1/T; % Not used! t = linspace(0,...

8 hours ago | 0

Answered

How do I create a mat file in a loop and store a matrix generated in that newly created mat file? (i also need to save every created mat file in the loop)

Instead of assigning a matrix to the sprintf() function, which of course you cannot do, sprintf('angry_%d%d.mat',j,k)=st_ma...

How do I create a mat file in a loop and store a matrix generated in that newly created mat file? (i also need to save every created mat file in the loop)

Instead of assigning a matrix to the sprintf() function, which of course you cannot do, sprintf('angry_%d%d.mat',j,k)=st_ma...

8 hours ago | 0

| accepted

Answered

How to write each slices from volume in MATLAB into jpg format?

You probably don't want to do that anyway, unless you use lossless jpeg2000 format. Use PNG for lossless compression for s...

How to write each slices from volume in MATLAB into jpg format?

You probably don't want to do that anyway, unless you use lossless jpeg2000 format. Use PNG for lossless compression for s...

9 hours ago | 0

| accepted

Answered

How to apply curvature(shape based features) on grayscale images in MATLAB?

Extract edges. Skeletonize. Fit lines with splines. Derivative of the spline equations give you the curvature at every point....

How to apply curvature(shape based features) on grayscale images in MATLAB?

Extract edges. Skeletonize. Fit lines with splines. Derivative of the spline equations give you the curvature at every point....

9 hours ago | 0

Answered

Saving Image with keeping the same histogram

If you save it as a .mat file, then the variable will be the same on a round trip through the file.

Saving Image with keeping the same histogram

If you save it as a .mat file, then the variable will be the same on a round trip through the file.

9 hours ago | 0

Answered

How can I warp images like to make the forehead larger in the image of a person? The transformation function? transformation for the attached image would be really helpful!

See Steve's blog: <https://blogs.mathworks.com/steve/2006/08/04/spatial-transformations-defining-and-applying-custom-transfor...

How can I warp images like to make the forehead larger in the image of a person? The transformation function? transformation for the attached image would be really helpful!

See Steve's blog: <https://blogs.mathworks.com/steve/2006/08/04/spatial-transformations-defining-and-applying-custom-transfor...

9 hours ago | 0

Answered

Calculating MAE of multiple images in different folders

It should be easy to modify the code in the FAQ slightly to do that: <http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_seque...

Calculating MAE of multiple images in different folders

It should be easy to modify the code in the FAQ slightly to do that: <http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_seque...

9 hours ago | 0

Answered

R2017a crashes every time on start in mac

Did you see this: <https://www.mathworks.com/support/bugreports/1549820?s_tid=answers_rc2-1_p4_MLT> And this: <http://matlab....

R2017a crashes every time on start in mac

Did you see this: <https://www.mathworks.com/support/bugreports/1549820?s_tid=answers_rc2-1_p4_MLT> And this: <http://matlab....

9 hours ago | 0

Answered

Replace cell text in Excel

Why not xlswrite(filename,Country,sheet,xlRange) Country should be a cell with a string inside of it, so this should wor...

Replace cell text in Excel

Why not xlswrite(filename,Country,sheet,xlRange) Country should be a cell with a string inside of it, so this should wor...

9 hours ago | 0

Answered

how to remove shadows from rgb image?

See <https://www.mathworks.com/matlabcentral/answers/?term=tag%3A%22shadow%22> and <https://www.udayton.edu/engineering/cente...

how to remove shadows from rgb image?

See <https://www.mathworks.com/matlabcentral/answers/?term=tag%3A%22shadow%22> and <https://www.udayton.edu/engineering/cente...

9 hours ago | 0

Answered

Shadow Recognition and Removal

See <https://www.mathworks.com/matlabcentral/answers/?term=tag%3A%22shadow%22>

Shadow Recognition and Removal

See <https://www.mathworks.com/matlabcentral/answers/?term=tag%3A%22shadow%22>

9 hours ago | 0

Answered

hi i am using axes in my figure to create black back ground. this figure is updated after each iteration. but problem is after 85 iteration my loop exectution time start increasing. its because of axes use . anyone knows why execution time increase

One way is you could create a new figure each time, then do your stuff, then delete it handleToFigure = figure; image(im...

hi i am using axes in my figure to create black back ground. this figure is updated after each iteration. but problem is after 85 iteration my loop exectution time start increasing. its because of axes use . anyone knows why execution time increase

One way is you could create a new figure each time, then do your stuff, then delete it handleToFigure = figure; image(im...

9 hours ago | 0

Answered

Using Vectorization to Calculate New Values Based on Surrounding Values

Just use conv2() with the valid option and then paste it onto a copy of the original. It's 3 lines of code. Hint: conv2Im...

Using Vectorization to Calculate New Values Based on Surrounding Values

Just use conv2() with the valid option and then paste it onto a copy of the original. It's 3 lines of code. Hint: conv2Im...

21 hours ago | 0

Answered

why am i getting an error for counts in histogram?

What kind of variables are HPperformance and Speed? Apparently Speed is a structure. Is HPperformance a structure array? If ...

why am i getting an error for counts in histogram?

What kind of variables are HPperformance and Speed? Apparently Speed is a structure. Is HPperformance a structure array? If ...

21 hours ago | 0

Answered

k mean clustering output with centre and solution space

Just call kmeans() like the examples in the help show you. For what it's worth, I attach another example of kmeans() to do gray...

k mean clustering output with centre and solution space

Just call kmeans() like the examples in the help show you. For what it's worth, I attach another example of kmeans() to do gray...

21 hours ago | 0

Answered

How do I take an average of fields in a structure?

One way totalMean = mean([BindingDataToSave.TotalVirusesBound]); totalStdDev = std([BindingDataToSave.TotalVirusesBound]...

How do I take an average of fields in a structure?

One way totalMean = mean([BindingDataToSave.TotalVirusesBound]); totalStdDev = std([BindingDataToSave.TotalVirusesBound]...

23 hours ago | 0

| accepted

Answered

How to translate the circle points to new co-ordinate system?

I have no idea what you're asking for. So I'll offer this. To fit a circle to x,y data, see the FAQ: <http://matlab.wikia....

How to translate the circle points to new co-ordinate system?

I have no idea what you're asking for. So I'll offer this. To fit a circle to x,y data, see the FAQ: <http://matlab.wikia....

1 day ago | 0

Answered

How do i compare vectors of images of same object that I have run through Alexnet using Euclidean Distance against other non object images

"is there certain values I have to enter between the bracketed colons?" No, it's fine as you have it. You can even use immse...

How do i compare vectors of images of same object that I have run through Alexnet using Euclidean Distance against other non object images

"is there certain values I have to enter between the bracketed colons?" No, it's fine as you have it. You can even use immse...

1 day ago | 1

| accepted

Answered

how to change the color of an image?

You can either adjust your colormap and display the gray scale image with the proper colormap. imshow(grayImage); colormap...

how to change the color of an image?

You can either adjust your colormap and display the gray scale image with the proper colormap. imshow(grayImage); colormap...

1 day ago | 0

Answered

Return max distance_transform

Post your image so we can see what pixels you want to know the distance from what _other_ pixels. At this point about all I can...

Return max distance_transform

Post your image so we can see what pixels you want to know the distance from what _other_ pixels. At this point about all I can...

1 day ago | 0

Answered

how can I make 2d auto-correlation and 2d cross-correlation for images dataset

Yes you need to have a loop. See the FAQ for code examples: <http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_f...

how can I make 2d auto-correlation and 2d cross-correlation for images dataset

Yes you need to have a loop. See the FAQ for code examples: <http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_f...

1 day ago | 0

Answered

i have to draw random dots and connect them by the shortest path between 2 certain dots.

See some of the links to the right, or try this: <https://www.mathworks.com/matlabcentral/answers/?term=tag%3A%22traveling+sales...

i have to draw random dots and connect them by the shortest path between 2 certain dots.

See some of the links to the right, or try this: <https://www.mathworks.com/matlabcentral/answers/?term=tag%3A%22traveling+sales...

1 day ago | 0

Answered

I want to obtain RGB histogram from mutiple image.Find the mean histogram for each of the 3 channel,Red, Green and Blue and store in 3 different histogram.I have created some code but it only work on ONE image..How do I proceed from this?

My attached demo plots RGB histograms for all images in a folder. Adapt as needed. <</matlabcentral/answers/uploaded_files/1...

I want to obtain RGB histogram from mutiple image.Find the mean histogram for each of the 3 channel,Red, Green and Blue and store in 3 different histogram.I have created some code but it only work on ONE image..How do I proceed from this?

My attached demo plots RGB histograms for all images in a folder. Adapt as needed. <</matlabcentral/answers/uploaded_files/1...

1 day ago | 0

Answered

could anyone tell me how to group different users of different combinations under the condition user present in one group should not be present in other group.

Not sure why you asked again, with less information, but see my answer in your duplicate question: <https://www.mathworks.com/ma...

could anyone tell me how to group different users of different combinations under the condition user present in one group should not be present in other group.

Not sure why you asked again, with less information, but see my answer in your duplicate question: <https://www.mathworks.com/ma...

2 days ago | 0

Answered

How to classify mark in answer sheet?

I did this long ago for someone. See attached example, and adapt as needed.

How to classify mark in answer sheet?

I did this long ago for someone. See attached example, and adapt as needed.

2 days ago | 0

| accepted

Answered

Could anyone tell me how to different combinations with respect to 6 users on the same coding.

If you have the Statistics and Machine Learning Toolbox, try this: >> c = combnk(1:6, 4) c = 3 4 5 6...

Could anyone tell me how to different combinations with respect to 6 users on the same coding.

If you have the Statistics and Machine Learning Toolbox, try this: >> c = combnk(1:6, 4) c = 3 4 5 6...

2 days ago | 0

| accepted

Answered

How to "plot" a surface?

Hint: [x, y] = meshgrid(..... % Then solve for z in terms of x and y. % Then call surf(x,y,z) It's literally 3...

How to "plot" a surface?

Hint: [x, y] = meshgrid(..... % Then solve for z in terms of x and y. % Then call surf(x,y,z) It's literally 3...

2 days ago | 0

| accepted

Answered

i don't know what is wrong with my code for finding edges

You can't have this: elseif I==i like the error message says. And you also switched to the badly-named j from the even ...

i don't know what is wrong with my code for finding edges

You can't have this: elseif I==i like the error message says. And you also switched to the badly-named j from the even ...

2 days ago | 2

Answered

How can I alter X axis from number of samples to a time domain?

You didn't have t be the same height as X - same number of rows. Try it this way: KneeTest2Array = rand(100, 3); % Whateve...

How can I alter X axis from number of samples to a time domain?

You didn't have t be the same height as X - same number of rows. Try it this way: KneeTest2Array = rand(100, 3); % Whateve...

2 days ago | 1

| accepted