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Computer graphic effect
Digital artifact
in
information science
, is any undesired or unintended alteration in data introduced in a digital process by an involved technique and/or technology.
Digital artifact can be of any content types including text,
audio
,
video
,
image
,
animation
or a combination.
Information science
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In information science, digital artifacts result from:
- Hardware malfunction: In
computer graphics
,
visual artifacts
may be generated whenever a hardware component such as the
processor
,
memory chip
, cabling malfunctions, etc., corrupts data. Examples of malfunctions include physical damage, overheating, insufficient voltage and
GPU
overclocking
. Common types of hardware artifacts are
texture
corruption and
T-vertices
in
3D graphics
, and
pixelization
in
MPEG
compressed video.
- Software malfunction: Artifacts may be caused by algorithm flaws such as decoding/encoding audio or video, or a poor
pseudo-random number generator
that would introduce artifacts distinguishable from the desired noise into statistical models.
- Compression
: Controlled amounts of unwanted information may be generated as a result of the use of
lossy compression
techniques. One example is the artifacts seen in
JPEG
and
MPEG
compression algorithms that produce
compression artifacts
.
- Quantization
: Digital imprecision generated in the process of converting analog information into digital space, is due to the limited granularity of digital numbering space. In computer graphics, quantization is seen as
pixelation
.
- Aliasing
: As a consequence of
sampling
or
sample-rate conversion
, energy from frequencies outside of the signal
frequency band
of interest are folded across multiples of the
Nyquist frequency
. This is typically mitigated by using an
anti-aliasing filter
.
- Filtering
: The process of filtering a signal, such as using an
anti-aliasing filter
, causes undesired alterations to the signal due to imperfections in the
frequency response
magnitude and phase, and due to the
time domain
impulse response
.
- Rolling shutter
, the line scanning of an object that is moving too fast for the image sensor to capture a unitary image.
- Error diffusion
: poorly-weighted kernel coefficients result in undesirable visual artifacts.
References
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External links
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