Doubt regarding processing of Upsampling and Downsampling Data in an Image.

Hello everyone,

I have an image of size 256 X 256. I downsampled the image row wise and column wise by 2 and my output is 128 X 128. Now if I Upsample the image by 2, then my final resultant image is of size 256 X 256. I know that upsampling means inserting zeros between the rows and columns.

If I use this upsampled image in my image processing, then is it something like I am using 50% of my original image data to represent the output?.

Answer 1

[Naman Chaturvedi]

Theoritically speaking, yes. You will actually be using just 25% of your original image's data points (50% in x, 50% in y). But this will not make any difference to how MATLAB will do computations on the original image than the computations on resultant image of the same size. It will just mean you are removing the higher frequency data from your image and then doing the processing.

[Sai Prakash Reddy Konda]

Thanks.. :) :)