- Visible or audible distortion introduced into digital information, such as images or audio signals, caused when a continuous line or transition is not smoothly captured or represented because of the low resolution or sampling rate of a digital medium.
- The appearance of jagged distortions in curves and diagonal lines in computer graphics.
- Present participle of alias.
- (signal processing, graphics, sound recording) Distortion caused by a low sampling rate, as Moire effect or stair-stepped edges.
aliasing - Computer Definition
A phenomenon that occurs when different analog continuous signals overlap and become indistinguishable. If the sampling of the analog waveform is too infrequent (less than half the highest frequency present), the digitally encoded signal cannot reliably be decoded faithfully. Rather, it can be reconstructed as an alias of the true signal. Aliasing is a major concern in the digital encoding of analog audio and video signals. Aliasing in video signals results in artifacts in video images that can manifest as jagged blockings or a tiling effect. See also analog, digital, encoding, PCM, and waveform.
In computer graphics, the stair-stepped appearance of diagonal lines when there are not enough pixels in the image or on screen to represent them realistically. Also called "stair-stepping" and "jaggies." See anti-aliasing.