Image Analyst

Last seen: Today

31,268 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

View details...

Answered
count of times if condition is met
Try this (no for loop needed): rowsInRange = ptarget(:,1) >= -0.5 & ptarget(:,1) <= 0.5 & ptarget(:,2) >= -0.5 & ptarget(:,2) <...

10 hours ago | 0

Answered
Index in position 2 is invalid. Array indices must be positive integers or logical values.
A thorough explanation of the error is given in the FAQ: https://matlab.fandom.com/wiki/FAQ#.22Subscript_indices_must_either_be_...

10 hours ago | 0

Answered
Use of Imagesc to show more than one image on a single figure
Try stitching them together if they're the same number of rows and color channels: wideImage = [rgbImage1, rgbImage2]; imagesc...

10 hours ago | 0

Answered
Matlab Newbie here / I want to multiselect files but it always gives me an error
Just make sure you include the folder because the user did not necessarily pick files in the current folder: [filename, folder]...

19 hours ago | 0

Answered
command window no output
I'd call tech support. https://matlab.fandom.com/wiki/FAQ#After_installation.2C_MATLAB_crashes_or_gives_an_error_message_when_I...

20 hours ago | 0

Answered
How can I get the slope of the peak?
Try this: % Your existing code: data=xlsread('data.xlsx',1,'A:B'); %import data,column A means the frame number; column B mean...

22 hours ago | 0

Answered
Unrecognized function or variable when reading an excel file.
Salinda: You can see from my code that your min pulse is 90.09 and the max is 138.2. That is why it always says critical. cl...

22 hours ago | 1

| accepted

Answered
How can i compute an interpolated curve?
Since the blue and yellow x,y vectors may not be the same length, you can't simply use interp1(). An approach I think might wor...

23 hours ago | 0

Answered
error with indices and vectors
A is not a vector so there is no (1 + 1/12)th element of it. A is a scalar. Maybe you meant A * (1 + i/12)??? i= 7.5; A= 300...

1 day ago | 0

Answered
I don't receive the error message I'm supposed to
That code is perfectly fine. Perhaps the bad code is mat=[3,5,7;1,2] % Preferred - commas between or mat = [3 5 7; 1 2] % No...

1 day ago | 0

Answered
Initialization of centroid for kmeans++ algorithm
I believe you can use the 'Replicates' and 'Start' options of kmeans().

2 days ago | 0

Answered
hello, any one help me , the function pop_loadset didn't work
Is that in it's own m-file, or is it a function in a program with a bunch of other functions in it? Are you sure you don't have...

2 days ago | 0

Answered
Regarding how to remove oscillations
Use medfilt1() or sgolayfilt() to get rid of small local oscillations.

2 days ago | 0

Answered
How to find four most repeated time ntervals?
Your stackoverflow code does not run. Good thing you came he to where the real experts are: >> test6 Error using matlab.io.Im...

2 days ago | 0

Answered
Splitting a binary image into 2 parts
Why not simply scan your image column by column with find() finding the topmost and bottommost row?

3 days ago | 0

Answered
Read text file and display binary
See the dec2bin() function.

3 days ago | 0

| accepted

Answered
Unrecognized function or variable when reading an excel file.
You need to initialize p because on the first time, you reference p but it never got inside the if block to be assigned: for L ...

3 days ago | 1

Answered
Convert red portion to white and the background to black . Second part is to detect road sign and put bounding box on it.
Try the Color Thresholder on the Apps tab of the tool ribbon. Otherwise look in the Computer Vision Toolbox or Automated Drivin...

4 days ago | 0

| accepted

Answered
how to convert double to uint8
Try this: % First convert G to a 3-D variable. G = cat(3, G, G, G); % Now convert it to uint8. It will clip values outside t...

5 days ago | 0

Answered
how to black out part of an image ?
See my masking and copy and paste demos. Also check out the Color Thresholder on the Apps tab or the tool ribbon.

5 days ago | 0

| accepted

Answered
How to change only the subsequent variables?
No. You'd have to use control-H and basically replace or skip them one at a time.

6 days ago | 1

Answered
Finding minima using for loop and if construct
You also need to start at 2 and end at the end-1 for i = 2 : length(zpoint)-1 if zpoint(i) < zpoint(i+1) && zpoint(i) < zp...

6 days ago | 0

Answered
How do I prompt a user for their name and age, then display a sentence
Hint: Use input() and fprintf(): userResponse = input(........................... fprintf('Hello %s in ......................\...

6 days ago | 0

Answered
Image Processing Toolbox exist or not
It may be installed but you may not have a license for it. For example if you are using a shared pool of licenses with 5 licens...

6 days ago | 0

Answered
The probability of winning
For even more fun, why not run a Monte Carlo experiment to empirically determine the probability and then plot the probability a...

6 days ago | 1

Answered
how to use mouse scroll to zoom in/out when using imtool?
I don't think you can, unfortunately. You have to either: Use the + and - magnifying glass icons above the image at the upper ...

6 days ago | 0

Answered
Averaging fluctuating curves in a single one
Assuming they all have values at the same set of x coordinates, just average them: yMean = (y1+y2+y3+y4+y5+y6+y7+y8+y9) / 9; o...

6 days ago | 0

| accepted

Answered
How do i find the location by using max and find function?
Don't use max() - it only gives the location of the first global max, not all of them (in the case the max occurs in more than o...

7 days ago | 0

| accepted

Answered
Fitting a nonlinear curve to a small dataset
Any idea of what curve you want to fit it to? Like a polynomial, or an exponential decay (demo attached), or something else? T...

7 days ago | 1

| accepted

Answered
Find the column names and total number of columns having all the entries as NaNs
If abc is your matrix, try this nanMap = isnan(abc(2:end, :)); % Ignore first row. columns = find(all(nanMap, 1)); Not sure w...

7 days ago | 0