Specific image intensity for further processing.

How do i select a specific intensity of an image? For example i would like to process only the intensity of 150 on grayscale image.

Answer 1

[Ben11]

Try this:

PixelsofInterest = (YourImage == 150); % get the location of the pixels you want to analyze

imshow(PixelsofInterest)

Answer 2

[Image Analyst]

What does "process" mean? It's trivial to find a "map" - a binary image - that says where the pixels with value 150 are.

binaryImage = grayImage == 150;

But what you do after that depends on what you want to do. If you just want a 1D list of pixel values, you can do

pixelValues = grayImage(binaryImage); % Of course they will all equal 150.

If you want the sum of the pixels (the count), do

totalArea = sum(binaryImage(:));

If you want the perimeter, Solidity, Equivalent circular Diameter, or something like that, you'll have to do

labeledImage = bwlabel(binaryImage);
measurementsStructure = regionprops(labeledImage, grayImage, 'all');

You can pass in specific measurements instead of 'all' if you know what they are.

See the Image Segmentation Tutorial in my File Exchange for a better discussion and demo. http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862

[kwan karmeng]

I want to perform bilinear interpolation on the image intensity.

[Image Analyst]

What are you interpolating between? And what does the 150 have to do with that???

[kwan karmeng]

I want to interpolate the specific intensity, to remove specular reflection actually.

[Image Analyst]

That didn't answer either question. But maybe you want roifill().