I'm working on a simple cover art and I initially designed it like this:
This image is 400 x 400 pixels. However, now I have upscaled it and added some cool stuff to the image to make it look like this:
This image is 1920 x 1080 as it's the right size for video's. I've also have some other sizes for various other uses.
The problem is that there are little upscaling arteffects from upscaling the small image. As you can see all of the squares in the bottom image have little "spikes" instead of a straight line. I tried removing these spikes by hand using the pen tool in paint.net however it's slow and I was hoping it could be done better.
As far as I know you cannot diagonally select inside paint.net otherwise I could use that to select all the spikes and then delete them.
Is there a simple way to delete the spikes and smothe the squares inside the image in paint.net?