Aliasing vs AntiAliasing

ALIASING:

Aliasing is an effect that causes different signals to become indistinguishable from each other during sampling.It is used in the field of digital signal processing.

• Aliasing is the term defined in different subjects like physics and computing.
• In physics aliasing means misidentification of a signal frequency, introducing distortion or error.
• In computing aliasing means the use of aliases to designate files, commands, addresses, or other items.

DESCRIPTION:

• Aliasing is an effect that causes different signals to become indistinguishable (or aliases of one another) when sampled. It also refers to the distortion or artifact that results when the signal reconstructed from samples is different from the original continuous signal.
• Aliasing is generally avoided by applying low pass filters- anti-aliasing filters to the analog signal before sampling.
•  If the 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.

IMAGES FOR ALIASING:

• Aliasing is the visual stair-stepping of edges that occurs in an image when the resolution is too low. Anti-aliasing is the smoothing of jagged edges in digital images by averaging the colors of the pixels at a boundary.
• The letter on the left is aliased.The letter on the right hand side is anti aliased applied to make the edges appear more smoother.

ANTIALIASING:

In computer graphics, antialiasing is a software technique for diminishing jaggies - stairstep-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.

• Anti-aliasing may refer to any of a number of techniques to combat the problems of aliasing in a sampled signal such as a digital image or digital audio recording.
• Anti-aliasing is a technique used in digital imaging to reduce the visual defects that occur when high-resolution images are presented in a lower resolution. 
• Anti-aliasing removes jagged edges by adding subtle color changes around the lines, tricking the human eye into thinking that the lines are not jagged.

Antialiasing is often seen as anti-aliasing or AA, and is sometimes called oversampling.

How Does Antialiasing Work?

• when rendering images for display on a monitor, they're broken down into tiny square elements called pixels. This process results in lines and edges that often appear jagged.
• Anti-aliasing reduces this problem by applying a particular technique to smooth out the edges for a better overall picture.
• By sampling pixels around the edges, antialiasing adjusts the color of the surrounding pixels, blending away the jagged appearance.Although the pixel blending removes the sharp edges, the antialiasing effect might make the pixels fuzzier.

Types of Antialiasing:

Super sample Antialiasing(SSAA)

Multi sample Antialiasing(MSAA)

Adaptive Antialiasing

Coverage Sampling Antialising(CSAA)

Enhanced Quality Antialiasing(EQAA)

Fast Approximate Antialiasing(FXAA)

Temporal Antialiasing(TXAA)

IMAGES FOR ANTIALIASING