Pixelation on my sketches

Hi There, total beginner to processing!

I’ve been playing around with the program and all of a sudden my sketches have become pixelated when I preview them (please see screenshot attached). I’m using the exact same code as I previously was. The only thing I’ve changed which I can think of is, I’ve installed, ‘ffmpeg’. The pixelation is quite minimal however it’s still driving my nuts as my initial sketches where previewing and exporting crisply.

Any help much appreciated!!

Screenshot 2021-08-23 at 15.51.37|498x500

Another example of my sketch window appearing more pixelated, is when I compare the quality between my preview window and the sketch running in the link below,

In the link the quality is far crisper then when I run it. Why would this be?

Again any help much appreciated!