Aliasing & Anti-aliasing

Before knowing anti-aliasing we should know what is aliasing.
Aliasing:-

• When a digital image is viewed, a reconstruction is performed by a display or printer device, and by the eyes and the brain.
• If image data is processed in some ways during sampling or reconstruction, the reconstructed image will differ from the original image, and an alias is seen.
• Aliasing can be caused either by the sampling stage or the reconstruction stage.
• If aliasing happens at sampling stage we can call it pre-aliasing and if it happens at reconstruction stage we can call it post-aliasing.

Anti-aliasing:-

• Anti-aliasing is a software technique for diminishing jaggies-stair step-like lines that should be smooth
• Jaggies occur because the output device, the monitor or printer, doesn't have a high enough resolution to represent a smooth line.
• To create high quality images we should understand anti-aliasing

Notes