How to realize the ZOOM IN function to compare the results in the paper?

[finger1517]

in many images restoration papers and image super resolution papers,
the images showed like below, are there any code provided in python or matlab there to do the ZOOM IN job?
I am a rookie in this area, so I would like to thank you all for giving advice or responces

[cszn]

https://github.com/cszn/KAIR/tree/master/matlab