stretching or compressing part of a matrix

I have 400 by 400 pixels data set as in the attached txt file. When plotting it, the final figure is having a trapezoidal shape.

Is it possible in matlab to stretch the lower part of the figure or to compress the uppper part to have a square final shape.

Thanks for help.

[Stephen23]

https://www.mathworks.com/help/images/image-registration-and-geometric-transformation.html

M = readmatrix('Evsky.txt');
imshow(M,[])