How to normalize the scale of an image to make it scaling invariant?

I want to make my image to be scaling invariant by normalizing the scale.

Answer 1

[Ayush]

Hi Abdul,

scaling invariance can be achieved in the following way through normalization:

• Normalization : You can normalize the scale of an image by making the highest dimension of the image equal to a given "target size". This way, the image also becomes scaling invariant. Here's a pseudo code for normalization of the image in order to make it scaling invariant.

function normalizedImage = normalizeScale(image, targetSize)
    % Get the dimensions of the image
    [height, width, ~] = size(image);
    
    % Calculate the scale factor
    scaleFactor = targetSize / max(height, width);
    
    % Calculate the new dimensions
    newWidth = round(width * scaleFactor);
    newHeight = round(height * scaleFactor);
    
    % Resize the image
    normalizedImage = imresize(image, [newHeight, newWidth]);
end

BONUS: Another way to achieve scaling-invariance is to use Scale-Invariant Feature Transform (SIFT). You can read more about it in the following documentation : https://in.mathworks.com/help/vision/ref/detectsiftfeatures.html

Hope it Helps!