how to calculate image pixels shift

hello,

i have two similar images, but one has a pixels shift compare to the other. how can i calculate the the offset (amount of pixels) for axis x and y?

Answer 1

[Manish]

Hi,

I see that you want to calculate pixel offset between two similar images.

You can achieve this by following the below steps:

• Process the Images: Start by reading your images that you want to process.
• Align Usingnormxcorr2: Use the‘normxcorr2’function to perform normalized cross-correlation on the images.
• Locate the peak value and calculate the offset based on the position of the peak.

Here is the sample code of above steps:

image1 = imread('img1.png');
image2 = imread('img2.png');
crossCorrMatrix = normxcorr2(image2, image1);
[maxCorr, maxIndex] = max(abs(crossCorrMatrix(:)));
[yPeak, xPeak] = ind2sub(size(crossCorrMatrix), maxIndex);
yOffset = yPeak - size(image2, 1);
xOffset = xPeak - size(image2, 2);
fprintf('Offset in X: %d pixels\n', xOffset);
fprintf('Offset in Y: %d pixels\n', yOffset);

Refer to the documentation link below for more information on the‘normxcorr2’function:

• https://www.mathworks.com/help/images/ref/normxcorr2.html

Hope it helps!