* Chrominance or chroma, one of the two components of a television signal

In systems historically based on NTSC standards, for reasons originally related to the Chrominance subcarrier in analog NTSC TV systems, the exact frame rate is often the nominal frame rate divided by 1. 001 — so, for example, a nominal 30 fps sequence is actually shot at 30 / 1. 001 = 29. 97002997 ... fps.

Chrominance is usually represented as two color-difference components: U

Chrominance is represented by the U-V color plane in PAL and SECAM video signals, and by the I-Q color plane in NTSC.

Chrominance is measured using two methods — color saturation, encoded as the amplitude, or gain, of the subcarrier signal, and hue, encoded as the subcarrier's phase.

For NTSC, Beta HiFi worked by placing a pair of FM carriers between the chroma ( C ) and luminance ( Y ) carriers, a process known as frequency multiplexing.

Y ′ is the luma component and C < sub > B </ sub > and C < sub > R </ sub > are the blue-difference and red-difference chroma components.

Y ′ CbCr is used to separate out a luma signal ( Y ′) that can be stored with high resolution or transmitted at high bandwidth, and two chroma components ( C < sub > B </ sub > and C < sub > R </ sub >) that can be bandwidth-reduced, subsampled, compressed, or otherwise treated separately for improved system efficiency.

where S < sub > ab </ sub > is the saturation, L * the lightness and C *< sub > ab </ sub > is the chroma of the color.

M is proportional to the chroma C (), thus the CIECAM02 definition bears some similarity to the CIELUV definition.

In the CIE 1976 L * a * b * and L * u * v * color spaces, the unnormalized chroma is the radial component of the cylindrical coordinate CIE L * C * h ( lightness, chroma, hue ) representation of the L * a * b * and L * u * v * color spaces, also denoted as CIE L * C * h ( a * b *) or CIE L * C * h for short, and CIE L * C * h ( u * v *).

The chroma in the CIE L * C * h ( a * b *) and CIE L * C * h ( u * v *) coordinates has the advantage of being more psychovisually linear, yet they are non-linear in terms of linear component color mixing.

Because video signals are recorded in component form instead of the S-Video ( Y / C ) color under method used by S-VHS, standard definition image quality for W-VHS is typically much higher, due to the lack of noise caused by a chroma sub-carrier.

** High-quality Y / C ( S-Video ) ( 8-pin DIN plug ) with chroma / luma out and sound in + out, used with some Commodore video monitors ( DIN-to-phono plug converter delivered with monitor ).

Chromatography ( from Greek χρῶμα chroma " color " and γράφειν graphein " to write ") is the collective term for a set of laboratory techniques for the separation of mixtures.

Digital video and digital still photography systems sometimes use a luma / chroma decomposition for improved compression.

Another example is chroma subsampling: the use of color spaces such as YIQ, used in NTSC, allow one to reduce the resolution on the components to accord with human perception – humans have highest resolution for black-and-white ( luma ), lower resolution for mid-spectrum colors like yellow and green, and lowest for red and blues – thus NTSC displays approximately 350 pixels of luma per scanline, 150 pixels of yellow vs. green, and 50 pixels of blue vs. red, which are proportional to human sensitivity to each component ...

In color systems that use chroma subsampling, the multi-component concept of a pixel can become difficult to apply, since the intensity measures for the different color components correspond to different spatial areas in such a representation.

The first " magazine-cover " chroma key was a photo of two helmeted policemen ( for the Clark interview segment ).

Chroma key compositing, or chroma keying, is a special effects / post-production technique for compositing ( layering ) two images or video streams together based on color hues ( chroma range ).

Film set for The Spiderwick Chronicles ( film ) | The Spiderwick Chronicles, where a special effects scene using bluescreen chroma key is in preparation.

Unlike baseline DV, DVCPRO uses locked audio and 4: 1: 1 chroma subsampling for both 50 Hz and 60 Hz variants to decrease generation losses.

In time, it featured synthesized music and, toward the end of its run, early chroma key technology added a new dimension to the story settings sometimes used for the musical numbers.

Today, only high-end equipment processing uncompressed signals uses a chroma subsampling of 4: 4: 4 with identical resolution for both brightness and color information.

The professional CCIR 601 digital video format also uses Y ' CbCr at the common chroma subsampling rate of 4: 2: 2, primarily for compatibility with previous analog video standards.

The show is most noted for its use of blue screen chroma key ( an idea borrowed by Tim Child from weather forecasts, where it had just started to be used ) and use of ' virtual reality ' interactive gameplay on television.

It comprises various tools for video switching, chroma keying, character generation, animation, and image manipulation.

This led to a wide range of possible chroma levels — up to the high 30s for some hue – value combinations ( though it is difficult or impossible to make physical objects in colors of such high chromas, and they cannot be reproduced on current computer displays ).

Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance.

That there is some " bleeding " of luminance and color information between the luma and chroma components in video, the error being greatest for highly saturated colors and noticeable in between the magenta and green bars of a color bars test pattern ( that has chroma subsampling applied ), should not be attributed to this engineering approximation being used.

Both its saturation and brightness falling short of 100 %, red-violet is not a pure chroma.

Typically, the chrominance bandwidth is reduced in analog composite video by reducing the bandwidth of a modulated color subcarrier, and in digital systems by chroma subsampling.

Since the theory of electric charge is dubbed " electrodynamics ", the Greek word " chroma " Χρώμα ( meaning color ) is applied to the theory of color charge, " chromodynamics ".

Though most of the pattern is removed from PAL and NTSC-encoded signals with a comb filter ( designed to segregate the two signals where the luma spectrum may overlap into the spectral space used by the chroma ) by modern displays, some can still be left in certain parts of the picture.

The chroma keying technique is commonly used in video production and post-production.

In analog color TV, color is represented by the phase of the chroma subcarrier relative to a reference oscillator.

A usable green screen example, which matches how chroma key was done on an optical printer, is f ( r, g, b )

The Munsell system describes a color in three dimensions, hue, value ( lightness ), and chroma ( color purity ), where chroma is the difference from gray at a given hue and value.

Using this knowledge allowed RCA to develop a system in which they discarded most of the blue signal after it comes from the camera, keeping most of the green and only some of the red ; this is chroma subsampling in the YIQ color space.

VHS tapes have approximately 3 MHz of video bandwidth and 400 kHz of chroma bandwidth, which is achieved at a relatively low tape speed by the use of helical scan recording of a frequency modulated luminance ( black and white ) signal, with a down-converted " color under " chroma ( color ) signal recorded directly at the baseband.

In modern-day digital terminology, NTSC VHS is roughly equivalent to 333x480 pixels luma and 40x480 chroma resolutions ( 333x480 pixels = 159, 840 pixels or 0. 16MP ( 1 / 6 of a MegaPixel ))., while PAL VHS offers the equivalent of about 335x576 pixels luma and 40x240 chroma ( the vertical chroma resolution of PAL is limited by the PAL color delay line mechanism ).

The frequency modulation of the VHS luminance signal is limited to 3 megahertz which makes higher resolutions technically impossible even with the highest-quality recording heads and tape materials, but an HQ branded deck includes luminance noise reduction, chroma noise reduction, white clip extension, and improved sharpness circuitry.