28,793 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

Answered

How can make a vector from a structure?

T(100).xi already IS a vector. You can simply use it as x: plot(T(100).xi, T(100).yi, 'b-'); grid on; Or you can take all of...

How can make a vector from a structure?

T(100).xi already IS a vector. You can simply use it as x: plot(T(100).xi, T(100).yi, 'b-'); grid on; Or you can take all of...

약 8시간 ago | 0

| accepted

Answered

How to find x and y value of top corner of the image

See my attached Optical Mark detection demo.

How to find x and y value of top corner of the image

See my attached Optical Mark detection demo.

약 23시간 ago | 0

Answered

How to select images from nested folder?

Have you looked at imageDatastore()? Or dir() using two asterisks as the file pattern?

How to select images from nested folder?

Have you looked at imageDatastore()? Or dir() using two asterisks as the file pattern?

약 23시간 ago | 0

Answered

How to find the area of a segmented image in matlab?

You need to invert your image so that your black region of interest is white. Then call sum() to get the number of pixels: num...

How to find the area of a segmented image in matlab?

You need to invert your image so that your black region of interest is white. Then call sum() to get the number of pixels: num...

1일 ago | 2

Answered

Image Segmenter app - Manual Threshold - how is calculated?

The threshold while using the "Manual Threshold" option is set by you moving the slider. If it makes a guess at the threshold to...

Image Segmenter app - Manual Threshold - how is calculated?

The threshold while using the "Manual Threshold" option is set by you moving the slider. If it makes a guess at the threshold to...

1일 ago | 0

| accepted

Answered

getting coordinates from a picture

Well, you could use image analysis: clc; % Clear the command window. close all; % Close all figures (except those of imtoo...

getting coordinates from a picture

Well, you could use image analysis: clc; % Clear the command window. close all; % Close all figures (except those of imtoo...

3일 ago | 1

| accepted

Answered

How to use the sum command to get both the sum and output in the same array

Try this: clc % How to get the 4th col to have summation of cols 1:3? %% Input % Array initalization samp(10,4) = zeros % ...

How to use the sum command to get both the sum and output in the same array

Try this: clc % How to get the 4th col to have summation of cols 1:3? %% Input % Array initalization samp(10,4) = zeros % ...

4일 ago | 0

| accepted

Answered

how to define the location of points within a shape that is invariant to shape transformation?

There are lots of points inside the triangle that are still inside it after you transform the triangle's shape and location. ...

how to define the location of points within a shape that is invariant to shape transformation?

There are lots of points inside the triangle that are still inside it after you transform the triangle's shape and location. ...

4일 ago | 0

Answered

Measuring distance of an object using 2 stereo vision cameras

Do you have the Computer Vision Sytem Toolbox? If so, use the camera calibration functionality. See the links on the right han...

Measuring distance of an object using 2 stereo vision cameras

Do you have the Computer Vision Sytem Toolbox? If so, use the camera calibration functionality. See the links on the right han...

4일 ago | 0

| accepted

Answered

area of many cracks in image

What I'd do is: Take a photo of a completely uniform white sheet to get a background that you can use for lens shading correcti...

area of many cracks in image

What I'd do is: Take a photo of a completely uniform white sheet to get a background that you can use for lens shading correcti...

4일 ago | 0

| accepted

Answered

How to find the median filtered image after doing subtracting averaged image from original image

filteredImage = medfilt2(differenceImage, [7, 7]); Adapt as needed. I've never heard of or used the fibermetric() function.

How to find the median filtered image after doing subtracting averaged image from original image

filteredImage = medfilt2(differenceImage, [7, 7]); Adapt as needed. I've never heard of or used the fibermetric() function.

5일 ago | 0

Answered

How can data gradually be exported to an Excel file?

You could just read in the existing worksheet and find out the last row: if isfile(filename) % Read in existing file to ge...

How can data gradually be exported to an Excel file?

You could just read in the existing worksheet and find out the last row: if isfile(filename) % Read in existing file to ge...

5일 ago | 0

Answered

Gaussian noise on dicom images

Try changing the input parameters for imnoise() so that it adds less noise. Attach your image if you need more help.

Gaussian noise on dicom images

Try changing the input parameters for imnoise() so that it adds less noise. Attach your image if you need more help.

5일 ago | 0

Answered

how to add jpeg toolbox?

The answer is in the link you posted: If you find this software useful, or if you would like to contribute to the proj...

how to add jpeg toolbox?

The answer is in the link you posted: If you find this software useful, or if you would like to contribute to the proj...

5일 ago | 0

Answered

Why does the image after subtracting the original image from average image displays a black screen

Some or all of your values may be small (too dark to see) or would be negative (and so they will be clipped to zero if you have ...

Why does the image after subtracting the original image from average image displays a black screen

Some or all of your values may be small (too dark to see) or would be negative (and so they will be clipped to zero if you have ...

5일 ago | 1

Answered

How to fit ellipse equation through segment of ellipse?

Have you tried the FAQ: https://matlab.fandom.com/wiki/FAQ#How_can_I_fit_an_ellipse_or_other_shape_to_a_set_of_XY_data.3F

How to fit ellipse equation through segment of ellipse?

Have you tried the FAQ: https://matlab.fandom.com/wiki/FAQ#How_can_I_fit_an_ellipse_or_other_shape_to_a_set_of_XY_data.3F

5일 ago | 0

Answered

extract each ten values

Try a loop to get the contents of the cells in your cell array, then extract 10 elements and move back towards the beginning of ...

extract each ten values

Try a loop to get the contents of the cells in your cell array, then extract 10 elements and move back towards the beginning of ...

5일 ago | 2

| accepted

Answered

How to transform a unit8 variable into a double one?

doubleVar = double(uintVar); Replace with your actual variable names, of course.

How to transform a unit8 variable into a double one?

doubleVar = double(uintVar); Replace with your actual variable names, of course.

5일 ago | 0

Answered

How can I solve this problem?

You chose a threshold where there were no blobs. Pick a threshold where you actually have some blobs present. But you can't be...

How can I solve this problem?

You chose a threshold where there were no blobs. Pick a threshold where you actually have some blobs present. But you can't be...

5일 ago | 1

| accepted

Answered

MATLAB Answers Wish-list #5 (and bug reports)

In Firefox v67, if you click on the m-file attached to a question, it offers to open it in MATLAB. But if I say to open it in M...

MATLAB Answers Wish-list #5 (and bug reports)

In Firefox v67, if you click on the m-file attached to a question, it offers to open it in MATLAB. But if I say to open it in M...

5일 ago | 0

Answered

I need to create a cell array initializing each element in it to 3*1 null matrix.

I don't know about null. How about nan? for k = 1 : numel(F) F(k) = {nan(3, 1)}; end

I need to create a cell array initializing each element in it to 3*1 null matrix.

I don't know about null. How about nan? for k = 1 : numel(F) F(k) = {nan(3, 1)}; end

6일 ago | 0

Answered

How can I extract/detect, separate the wall from the window using vertical and horizontal line detection?

Try edge() and imfill(). Is it your assignment?

How can I extract/detect, separate the wall from the window using vertical and horizontal line detection?

Try edge() and imfill(). Is it your assignment?

6일 ago | 0

| accepted

Answered

For loop, Subscript indices must either be real positive integers or logicals ?

See the FAQ https://matlab.fandom.com/wiki/FAQ#How_do_I_fix_the_error_.22Subscript_indices_must_either_be_real_positive_integers...

For loop, Subscript indices must either be real positive integers or logicals ?

See the FAQ https://matlab.fandom.com/wiki/FAQ#How_do_I_fix_the_error_.22Subscript_indices_must_either_be_real_positive_integers...

6일 ago | 0

Answered

Coloring the desired specific region bounded by curves drawn using insert button and text using 'gtext'?

Try fill() or patch().

Coloring the desired specific region bounded by curves drawn using insert button and text using 'gtext'?

Try fill() or patch().

6일 ago | 0

| accepted

Answered

How to get edge line of from binary Image?

I suggest you improve your segmentation algorithm first. After that it will be so much easier to get the outlines with bwbounda...

How to get edge line of from binary Image?

I suggest you improve your segmentation algorithm first. After that it will be so much easier to get the outlines with bwbounda...

6일 ago | 0

Answered

(UPDATED) Need to find area of an image at half length

Why not just find the right and left half edges and fit lines through them, col1 = zeros(1, rows); col2 = zeros(1, columns); ...

(UPDATED) Need to find area of an image at half length

Why not just find the right and left half edges and fit lines through them, col1 = zeros(1, rows); col2 = zeros(1, columns); ...

6일 ago | 0

| accepted

Answered

Specify What to Edit for User

I'd just use app designer or guide and make a gui with either 3 radio buttons or a drop down list (popup) with three selections....

Specify What to Edit for User

I'd just use app designer or guide and make a gui with either 3 radio buttons or a drop down list (popup) with three selections....

7일 ago | 0