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Image Analyst


28,688 total contributions since 2010

Senior Scientist and Inventor 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. 40+ 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

Image Analyst's Badges

  • 36 Month Streak
  • Most Accepted 2014
  • Thankful Level 4
  • Grand Master
  • Revival Level 4
  • Knowledgeable Level 4
  • First Answer

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Contributions in
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Answered
Direction gradient value of edge pixel
As you know, the gradient is a vector. So you can get magnitude and direction from imgradient(), or get the direction as x and ...

6 hours ago | 1

Answered
How to save a plot as an image with titles and x y lables
Click on the toolbar save icon (if you have the toolbar showing) or use File/SaveAs (if youhave the pulldown menu showing). Or ...

6 hours ago | 0

Answered
Trace Image from Intensity
Try mask = grayImage > someThreshold boundaries = bwboundaries(mask)

21 hours ago | 0

Answered
Can you remove certain characters from first column and each row of a table?
In a loop, get the filename and extract the last character(s) that are the number or use fileparts. Untested code: for k = 1 :...

22 hours ago | 1

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Answered
How to change the background colour of this image to 0 and foreground colour to 1 to make it binary.
You'd need mask = ~(redChannel ~= 0 & greenChannel == 0 & blueChannel == 255); % Mask the image using bsxfun() function to mul...

1 day ago | 0

Answered
Calculation of radial and tangential component of wind
Wouldn't it just be the usual trig formulas? Untested code: rComponent = sqrt(dU.^2+dV.^2); angularComponent = atand2d(dV, dU...

2 days ago | 0

Answered
How can I find out Correlation between two image?
They're probably color. Do it on one color channel at a time, or use rgb2gray() to convert them to grayscale. Untested code: ...

2 days ago | 1

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Answered
How to declare a cell array of a particular size n ?
Use cell(): ca = cell(1, n);

2 days ago | 1

Answered
Removing Noise From Image
pcolor() is not the problem. The problem is in your actual data, nitrogenCellAveraged. That's what needs to be cleaned up.

2 days ago | 0

Answered
is it okay to delete it?
You can probably delete the installation of MATLAB under C:\Program Files\ACSYS2002\MATLAB and leave the one under C:\Program Fi...

2 days ago | 0

Answered
Pixel's edge strength
Use imgradient().

2 days ago | 0

Answered
after first imshow function, image is not shown
When you double click inside the polygon, it will show the other figures.

2 days ago | 0

Answered
how to do this stat in matlab?
The homework problem does not state how many rats were in the test so it's unclear if there are a bunch of rats with zero or inf...

2 days ago | 0

Answered
Can someone please help me remove my account?
We cannot. But someone can, if you send an email to support@mathworks.com.

3 days ago | 0

Answered
Calculate average of specific values in one table column
Try extracting the last column, then reshaping so that there are only 4 rows, then using mean(). % Extract last column of table...

6 days ago | 0

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Answered
Create multiple ROI in same image in App Designer and store the data in a struct
Just append it to your structure: roiStruct(end+1).roi = yourROI; yourROI could be any form, for example an ROI object, or an ...

6 days ago | 0

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Answered
How to know maximal x and y cordinate in image
To get the maximum pixel coordinate for an image, that's simply the number of rows and columns. [rows, columns, numberOfColor...

6 days ago | 0

Answered
How to retrieve intensities of a ROI in App Designer
See attached demos for masking.

7 days ago | 0

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Answered
How do I save multiple vectors and use them to display multiple plots at once
After you call plot() the first time, call "hold on" plot(................ hold on; % more calls to plot......

7 days ago | 0

Answered
Histogram from masked area of grayscale picture
Attach a .mat file containing your grayImage and mask. Alternatively, just do histogram(grayImage(mask), 256, 'EdgeColor', 'no...

8 days ago | 0

Answered
how to combine a GUI timer with battleship game
FYI, the MATLAB Facebook page has an item on Battleship: Battleship

8 days ago | 0

Answered
Corner detection in freehand drawings
Count the vertices. See my attached demo.

9 days ago | 0

Answered
Unable to perform assignment because the size of the left side is 1-by-1 and the size of the right side is 2-by-1.
cfs and fifs are both 2 values, so you're trying to stick two values into one index. Change the fs line to this and see what yo...

9 days ago | 1

Answered
the equivalent matlab code for areg ,absorb in stata
I don't understand your code at all. If you want to fit a polynomial, use polyfit(). For something more complicated, try fitnl...

9 days ago | 0

Answered
Error in matlab codes
Try getting rid of the brackets, which concatenate all the values from all the structures into a single array of 20 values, whic...

9 days ago | 0

Answered
How to evaluate a math function?
Try this: % Specify the start of the interval. x1 = 1; % The end of the interval is 0.01 after the start of the interval. x2...

9 days ago | 0

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Answered
How to convert RGB to hsv?
Why not simply use the built-in rgb2hsv() function: % load R and G and B data clear close all clc load('RGB.mat') subplo...

9 days ago | 0

Answered
How to use blockproc by location?
Yes, you can even do that without blockproc(). Here's how yourImage = uint8(255 * ones(yourImage)); that will turn every pixe...

9 days ago | 0

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Answered
Divide a data set into 4 parts so that the sum of each part 1/4th of the total
I'd just sort them and then take the CDF and look for percentages: c = cumsum(sort(data, 'ascend')); c = c / c(end); % Normali...

9 days ago | 1

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