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# Image noise

Image noise is random variation of brightness or color information in images, and is usually an aspect of electronic noise. [1]

58 relations: Acutance, Analog-to-digital converter, Aperture, Binomial distribution, Canon EOS 400D, Circuit noise level, Compression artifact, Dark-frame subtraction, Digital camera, Digital image, Digital single-lens reflex camera, Discretization, Dither, EMVA1288, Exposure (photography), F-number, Fat-tailed distribution, Film grain, Fixed-pattern noise, Four Thirds system, Full-frame digital SLR, Gain (electronics), Gaussian noise, Illuminance, Image, Image scanner, Image sensor, Interference (communication), Isotropy, Johnson–Nyquist noise, Leakage (electronics), Linda Shapiro, Median filter, Noise (electronics), Noise (radio), Noise (video), Noise reduction, Normal distribution, Photodiode, Photographic film, Photon, Pixel, Poisson distribution, Posterization, Quantization (image processing), Quantization (signal processing), Radio astronomy, Root mean square, Sensor, Shadow noise, ... Expand index (8 more) »

## Acutance

In photography, the term "acutance" describes a subjective perception of sharpness that is related to the edge contrast of an image.

## Analog-to-digital converter

In electronics, an analog-to-digital converter (ADC, A/D, or A-to-D) is a system that converts an analog signal, such as a sound picked up by a microphone or light entering a digital camera, into a digital signal.

## Aperture

In optics, an aperture is a hole or an opening through which light travels.

## Binomial distribution

In probability theory and statistics, the binomial distribution with parameters n and p is the discrete probability distribution of the number of successes in a sequence of n independent experiments, each asking a yes–no question, and each with its own boolean-valued outcome: a random variable containing a single bit of information: success/yes/true/one (with probability p) or failure/no/false/zero (with probability q.

## Canon EOS 400D

The EOS 400D, called Digital Rebel XTi in North America and EOS Kiss Digital X in Japan, is an entry-level digital single-lens reflex camera introduced by Canon on 24 August 2006.

## Circuit noise level

At any point in a transmission system, the ratio of the circuit noise at that point to an arbitrary level chosen as a reference.

## Compression artifact

A compression artifact (or artefact) is a noticeable distortion of media (including images, audio, and video) caused by the application of lossy compression.

## Dark-frame subtraction

In digital photography, dark-frame subtraction is a way to minimize image noise for photographs shot with long exposure times, at high ISO sensor sensitivity or at high temperatures.

## Digital camera

A digital camera or digicam is a camera that captures photographs in digital memory.

## Digital image

A digital image is a numeric representation, normally binary, of a two-dimensional image.

## Digital single-lens reflex camera

A digital single-lens reflex camera (also called digital SLR or DSLR) is a digital camera that combines the optics and the mechanisms of a single-lens reflex camera with a digital imaging sensor, as opposed to photographic film.

## Discretization

In mathematics, discretization is the process of transferring continuous functions, models, variables, and equations into discrete counterparts.

## Dither

Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images.

## EMVA1288

EMVA1288 is an electronic measurement standard developed by the European Machine Vision Association (EMVA).

## Exposure (photography)

In photography, exposure is the amount of light per unit area (the image plane illuminance times the exposure time) reaching a photographic film or electronic image sensor, as determined by shutter speed, lens aperture and scene luminance.

## F-number

The f-number of an optical system (such as a camera lens) is the ratio of the system's focal length to the diameter of the entrance pupil.

## Fat-tailed distribution

A fat-tailed distribution is a probability distribution that has the property, along with the other heavy-tailed distributions, that it exhibits large skewness or kurtosis.

## Film grain

Film grain or granularity is the random optical texture of processed photographic film due to the presence of small particles of a metallic silver, or dye clouds, developed from silver halide that have received enough photons.

## Fixed-pattern noise

Fixed-pattern noise (FPN) is the term given to a particular noise pattern on digital imaging sensors often noticeable during longer exposure shots where particular pixels are susceptible to giving brighter intensities above the general background noise.

## Four Thirds system

The Four Thirds System is a standard created by Olympus and Eastman Kodak for digital single-lens reflex camera (DSLR) and mirrorless camera design and development.

## Full-frame digital SLR

The term full frame or ff is used by users of digital single-lens reflex cameras (DSLRs) as a shorthand for an image sensor format which is the same size as 35mm format film.

## Gain (electronics)

In electronics, gain is a measure of the ability of a two-port circuit (often an amplifier) to increase the power or amplitude of a signal from the input to the output port by adding energy converted from some power supply to the signal.

## Gaussian noise

Gaussian noise is statistical noise having a probability density function (PDF) equal to that of the normal distribution, which is also known as the Gaussian distribution.

## Illuminance

In photometry, illuminance is the total luminous flux incident on a surface, per unit area.

## Image

An image (from imago) is an artifact that depicts visual perception, for example, a photo or a two-dimensional picture, that has a similar appearance to some subject—usually a physical object or a person, thus providing a depiction of it.

## Image scanner

An image scanner—often abbreviated to just scanner, although the term is ambiguous out of context (barcode scanner, CT scanner etc.)—is a device that optically scans images, printed text, handwriting or an object and converts it to a digital image.

## Image sensor

An image sensor or imaging sensor is a sensor that detects and conveys the information that constitutes an image.

## Interference (communication)

In communications and electronics, especially in telecommunications, interference is anything which modifies, or disrupts a signal as it travels along a channel between a source and a receiver.

## Isotropy

Isotropy is uniformity in all orientations; it is derived from the Greek isos (ἴσος, "equal") and tropos (τρόπος, "way").

## Johnson–Nyquist noise

Johnson–Nyquist noise (thermal noise, Johnson noise, or Nyquist noise) is the electronic noise generated by the thermal agitation of the charge carriers (usually the electrons) inside an electrical conductor at equilibrium, which happens regardless of any applied voltage.

## Leakage (electronics)

In electronics, leakage may refer to a gradual loss of energy from a charged capacitor.

## Linda Shapiro

Linda G. Shapiro is a professor in the Department of Computer Science and Engineering, a Professor of Electrical Engineering, and Adjunct Professor of Biomedical Informatics and Medical Education at the University of Washington.

## Median filter

The median filter is a nonlinear digital filtering technique, often used to remove noise from an image or signal.

## Noise (electronics)

In electronics, noise is an unwanted disturbance in an electrical signal.

## Noise (radio)

In radio reception, noise is the superposition of white noise and other disturbing influences on the signal, caused either by thermal noise and other electronic noise from receiver input circuits or by interference from radiated electromagnetic noise picked up by the receiver's antenna.

## Noise (video)

Noise, in analog video and television, is a random dot pixel pattern of static displayed when no transmission signal is obtained by the antenna receiver of television sets and other display devices.

## Noise reduction

Noise reduction is the process of removing noise from a signal.

## Normal distribution

In probability theory, the normal (or Gaussian or Gauss or Laplace–Gauss) distribution is a very common continuous probability distribution.

## Photodiode

A photodiode is a semiconductor device that converts light into an electrical current.

## Photographic film

Photographic film is a strip or sheet of transparent plastic film base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals.

## Photon

The photon is a type of elementary particle, the quantum of the electromagnetic field including electromagnetic radiation such as light, and the force carrier for the electromagnetic force (even when static via virtual particles).

## Pixel

In digital imaging, a pixel, pel, dots, or picture element is a physical point in a raster image, or the smallest addressable element in an all points addressable display device; so it is the smallest controllable element of a picture represented on the screen.

## Poisson distribution

In probability theory and statistics, the Poisson distribution (in English often rendered), named after French mathematician Siméon Denis Poisson, is a discrete probability distribution that expresses the probability of a given number of events occurring in a fixed interval of time or space if these events occur with a known constant rate and independently of the time since the last event.

## Posterization

Posterization or posterisation of an image entails conversion of a continuous gradation of tone to several regions of fewer tones, with abrupt changes from one tone to another.

## Quantization (image processing)

Quantization, involved in image processing, is a lossy compression technique achieved by compressing a range of values to a single quantum value.

## Quantization (signal processing)

Quantization, in mathematics and digital signal processing, is the process of mapping input values from a large set (often a continuous set) to output values in a (countable) smaller set.

## Radio astronomy

Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies.

## Root mean square

In statistics and its applications, the root mean square (abbreviated RMS or rms) is defined as the square root of the mean square (the arithmetic mean of the squares of a set of numbers).

## Sensor

In the broadest definition, a sensor is a device, module, or subsystem whose purpose is to detect events or changes in its environment and send the information to other electronics, frequently a computer processor.

## Shadow noise

Shadow noise or luminescence noise is an effect that digital lightening has on an image, specifically on the darker, or shadowed areas of the image.

## Shot noise

Shot noise or Poisson noise is a type of electronic noise which can be modeled by a Poisson process.

## Shutter speed

In photography, shutter speed or exposure time is the length of time when the film or digital sensor inside the camera is exposed to light, also when a camera's shutter is open when taking a photograph.

## Signal-to-noise ratio

Signal-to-noise ratio (abbreviated SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise.

## Television

Television (TV) is a telecommunication medium used for transmitting moving images in monochrome (black and white), or in colour, and in two or three dimensions and sound.

## Thin-film-transistor liquid-crystal display

A Thin-film-transistor liquid-crystal display (TFT LCD) is a variant of a liquid-crystal display (LCD) that uses thin-film-transistor (TFT) technology to improve image qualities such as addressability and contrast.

## Uniform distribution (continuous)

In probability theory and statistics, the continuous uniform distribution or rectangular distribution is a family of symmetric probability distributions such that for each member of the family, all intervals of the same length on the distribution's support are equally probable.

## Video

Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media.

## Visible-light astronomy

Visible-light astronomy encompasses a wide variety of observations via telescopes that are sensitive in the range of visible light (optical telescopes).

## References

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