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Image Analyst


28,583 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
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Answered
Add SINGLE element to array or vector
For an existing vector x, you can assign a new element to the end using direct indexing. For example x = [1 2 3] x(4) = 4 Ano...

1 hour ago | 2

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Answered
How to improve optic disc removal code?
Find algorithms in papers listed here in Vision Bibliography

12 hours ago | 0

Answered
how to calculate the area of an object?
You shouldn't calculate areas based on the grayscale image. You must segment it first into foreground and background areas and ...

1 day ago | 0

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Answered
Swap first and last word in a string
Here's one way: % Create sample string. str = 'one two three four five'; % Split apart into individual words without spaces. ...

5 days ago | 0

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Grouping small pixels to make larger usable cells.
Try superpixels(). Or try my attached RGB classifier demo. Or try my blockproc() demo.

5 days ago | 1

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Answered
Filtering outlier in 2D coordinate data
Well this works for "the problem I have at the moment", though there are even simpler methods, and more sophisticated methods. ...

5 days ago | 0

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Answered
subtract each pixel from average pixel value
Try (for an integer gray level image): newImage = double(yourImage) - meanValue; where you said you already have the meanValue...

5 days ago | 1

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User defined minimum Function
Try this: function colMins = GetColumnMins(m) % m is a matrix colMins = min(m, [], 1); You can rename GetColumnMins, m, and ...

5 days ago | 0

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Is the .jpg image one-dimensional and two-dimensional?
JPG images are already demosaiced. I think you're using a raw image. Raw images usually are not demosaiced - they're just red,...

8 days ago | 1

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Counting the number of a specific word in text.
Instead of A=input(filename,'s'); try this: [folder, baseFileName] = uigetfile('*.*'); filename = fullfile(folder, baseFileN...

9 days ago | 0

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How to plot like a movie this 30 heatmaps
See attached demo where I plot some stuff in a series, then construct a movie from the series of plots.

9 days ago | 0

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How can I find an image in its miniature form in another image ?
Use normxcorr2() with the template being the mini-image. See my canned demo, attached. Change my template to yours, which is t...

10 days ago | 0

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Answered
Pad empty spaces in matrix with 0
Try this: c1m_wrf = [1 4 6 3 7 3 ] c2m_wrf = [4 6 2 9] c3m_wrf = [5 5 8 2 5] c4m_wrf = [4 8 1 3 9 4 ] maxLength = max([leng...

10 days ago | 1

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Answered
Array indices must be positive integers or logical values.
It's a FAQ so see the FAQ for complete info: Click here for the FAQ In short, you can't start with x(0) since 0 is not an allow...

10 days ago | 0

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or operation on the columns of a matrix ?
Try rowHasOnes = any(S, 2); If not, then supply an example S and the expected result.

10 days ago | 0

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Answered
How to find pixel connect in column matlab
This will give you result = 1 1 1 2 2 0 0 0 0 0 exactly as you wanted (in your curr...

10 days ago | 1

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Answered
passing variable from one callback to another callback in gui
This is a FAQ, so See the FAQ document

10 days ago | 0

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How can I get the number between 2 numbers?
If you have the Image Processing Toolbox, you can simply use ismember() followed by regionprops() and in 2 lines of code be done...

10 days ago | 0

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stretch histogram for comparison
Try imhistmatch(). Or multiply the dark image by 2. Or imadjust().

10 days ago | 0

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Changing the brightness of an image using slider in Matlab GUI
It probably really is RGB even though it looks like RGB to you. You can cast all images to gray scale like this: ImageFile=imr...

10 days ago | 0

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Answered
How can I change the pixel RGB value of each frame of the video?
Just read in each frame into a variable, and then change it in whatever way you want. See attached examples.

11 days ago | 0

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inter distance between point to be more than a certain number
You can try my demo, that I've posted before. It's a pretty simple "try and reject or accept" method, but it's intuitive and we...

12 days ago | 0

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Answered
Problem of 2 images with different scale and orientation
You will need to spatially calibrate your images to real world units. See my attached demo for an example that you can adapt. ...

13 days ago | 1

Answered
Using inbuilt RANSAC function for circle fit in 2D data
Why RANSAC? Why not use the FAQ: https://matlab.fandom.com/wiki/FAQ#How_can_I_fit_a_circle_to_a_set_of_XY_data.3F

13 days ago | 0

Answered
How to take maximum vector from the image? Can anyone name the function
With g1 = g at time 1, and g2 = g at time 2, try t=0.1 bw1 = 255 / (1-t) + (1/(1-t)) * double(g1); t=0.2 bw2 = 255 / (1-t) +...

15 days ago | 0

Answered
I asked before but i can not reach the solution, so how can we plot our 4th order polynomial with given data by using polyval()?
Try this, where I fit both the original training points, and then a larger number of points to get a smoother curve, including i...

16 days ago | 0

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Conversion pixel size into mm ?
See my attached spatial calibration demo.

16 days ago | 0

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Matrix into Sub matrix of length 8
What did you try for reshape? Did you try reshape(A, [], 8)? A=[1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24...

17 days ago | 0

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Answered
How change Image/2d array proportions?
Use imresize(): [rows, columns, numberOfColorChannels] = size(yourImage) newWidth = round(columns * (210/25.4)) yourImage = i...

17 days ago | 1

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