MATLAB: Pixel Selection within a GUI

guiImage Processing Toolboximagesnanpixel selection

Okay soi have four small pictures within a GUI, i need the user select a single pixel from one of these four images. How would i go about selecting a pixel and getting the RGB value from that pixel. When i use impixel() it doesnt terminate after one click, is there a way to make it terminate after the user clicks once? I also keep getting NaN NaN NaN as the values when i use impixel() any idea why that would be happening? I would add code but its a GUI and there is just way too much to post here.

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Like I said in your duplicate question you should be able to get the RGB values once you have the row and column from ginput as

rgbTriplet = rgbImage(row, column, :);

rgbTriplet = impixel(rgbImage, column, row);

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MATLAB: How do i obtain a single pixel value in a grayscale image by clicking on it

See my interactive thresholding app : http://www.mathworks.com/matlabcentral/fileexchange/29372-thresholding-an-image. It should work beautifully for all type of grayscale images - let me know if it doesn't. Other than that, use ginput() to get the column,row coordinates

[column, row] = ginput(1);
grayLevel = image(row, column);

or use impixelinfo() to get the gray level "live" as you move the mouse around over the image.

MATLAB: Want to get these values in the code

If you just want to see the values on your GUI as you mouse around, use impixelinfo().

If you want to click on some pixels and get the values in an array, use impixel():

impixel(I) returns the value of pixels in the specified image I, where I can be a grayscale, binary, or RGB image. impixel displays the image specified and waits for you to select the pixels in the image using the mouse. If you omit the input arguments, impixel operates on the image in the current axes.
Use normal button clicks to select pixels. Press Backspace or Delete to remove the previously selected pixel. To finish selecting pixels, adding a final pixel, press shift-click, right-click, or double-click. To finish selecting pixels without adding a final pixel, press Return.
When you finish selecting pixels, impixel returns an m-by-3 matrix of RGB values in the supplied output argument. If you do not supply an output argument, impixel returns the matrix in ans. impixel always returns pixel values as RGB triplets, regardless of the image type:

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MATLAB: How do i obtain a single pixel value in a grayscale image by clicking on it

MATLAB: Want to get these values in the code

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