Aliasing and Anti-aliasing

What is aliasing

• Aliasing is a phenomenon that occurs when sampling a continuous function with insufficient resolution.

What is Anti-aliasing

• Anti aliasing is the application of techniques that reduce or eliminate aliasing.

Why is it necessary

• To make the graphics look more realistic
• Anti-aliasing is nothing but add additional pixels and make best image quality.

Kinds of Anti-aliasing types

• Basically, there are only three main methods of anti-aliasing: Super-sampling, Multi-sampling and Post-Processing.

Super-sample Anti-aliasing (SSAA):

• This is the type of AA that creates the best image quality. It is “pure” AA with no compromises. All the other AA technologies exist because SSAA is very slow.

Multi-sample Anti-aliasing (MSAA):

• For years now, MSAA has been the standard method for anti-aliasing, as it has a good balance between performance and image quality.

Post-processing Anti-aliasing (PPAA):

• Instead of actively recalculating the image with pure hardware power, "PPAA" can be understood to be more of a software-based smoothing/softening filter.

Examples of Anti-aliasing

• The below figure explained about above figure.

• In the below figure edges over hidden by Anti-aliasing process.