Answer:
Pixel distortion or how you will find on the internet Piexelation.
Step-by-step explanation:
In computer graphics, pixelation is caused by the display of a bitmap or a section of a bitmap so large that individual pixels, small colored square display elements that make up the bitmap, are visible. This image is said to be pixelated. This effect is more visible in circular images, especially in circles and circumferences, which are slightly oval in shape when presented.