how to convert unit8 type images to logical type

if true

    myFolder = 'E:\\inverted\\i1';

    for PicNum = 100:-1:1;
        fullFileName = fullfile(myFolder,sprintf('%d.bmp',PicNum));
        fprintf(1, 'Now reading %s\n', fullFileName);

        imageArray{PicNum}=imread(fullFileName);
        logical(imageArray{PicNum});//here im trying to convert my images to logical but its not happening

        imshow(imageArray{PicNum});  % Display image.

    end

 end

Answer 1

[Image Analyst]

To convert a gray level image to a logical binary image you must threshold:

binaryImage = grayImage > someValue;

[neha viswanath]

my images are already converted to logical .but in the above code im getting a cell named imageArray which has 100 unit8 type 50*50 size images.so i used logical() to convert them to 0-1 type.but its not working.now i need to convert every unit8 to logical.

[Image Analyst]

The images are NOT already logical. They may have gray levels of only 0 and 1 or of only 0 and 255 but after you use imread() they are not logical - that's why you're trying to convert them. If I assume you just have the two gray levels, then you can do this:

logicalImage = imageArray{PicNum} ~= 0;

logicalImage here will truly be a logical image with values of true and false, not 0 and 255 or whatever. Then proceed to analyze or process logicalImage in whatever way you need to.

[neha viswanath]

thankyou sir

[neha viswanath]

sir,I need to access each image in cell array.

if true
  for i=1:1:100
  feature_extractor(logicalImage{i});
end
end
so i could get features of all the images in 'ans'.with the above code i could not accomplish my task.can you please help me out.

Answer 2

[Adam]

imageArrayLogical = cellfun( @(im) logical(im), imageArray, 'UniformOutput', false );

or you can just do it in a for loop if you prefer. Note the result is still a cell array of your data so you still have to index into it using cell notation.