RGB

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Related to RGB color model: CMYK color model

RGB

Red, Green, Blue. The three colours of light which can be mixed to produce any other colour. Coloured images are often stored as a sequence of RGB triplets or as separate red, green and blue overlays though this is not the only possible representation (see CMYK and HSV). These colours correspond to the three "guns" in a colour cathode ray tube and to the colour receptors in the human eye.

Often used as a synonym for colour, as in "RGB monitor" as opposed to monochrome (black and white).

RGB

(1) (Red Green Blue) A designation for motherboards and peripherals that display colors for a visual effect. For example, the backlit keys on an RGB keyboard can alternate through a rainbow of colors. See RGB keyboard, RGB motherboard and RGB RAM.

(2) (Red Green Blue) The computer's native color space and the system for capturing and displaying color images electronically. All TV, computer and electronic display screens create color by generating red, green and blue (RGB) lights. This is because our eyes are sensitive to red, green and blue, and our brain mixes the colors together (see trichromaticity). See RGBW and RGBY.

Capturing
Cameras and scanners capture color with sensors that record the varying intensities of red, green and blue at each pixel location in the frame. See 24-bit color, CCD sensor, CMOS sensor, scanner and digital camera.

Display and Printing (RGB and CMYK)
For screen display, red, green and blue subpixels (dots) are energized to the appropriate intensity. When all three subpixels are turned on high, white is produced. As intensities are equally lowered, shades of gray are derived. The base color of the screen appears when all subpixels are turned off.

For printing on paper, the CMYK color space is used, not RGB. Combinations of cyan, magenta, yellow and black ink make up the colors. White is typically derived by using white paper and no ink for those areas; however, if white is of critical importance, a white spot color can be added to the CMYK process. See CMYK and spot color.

Video Processing (RGB or YUV)
TV/video signals are mostly in the YUV color space. They are converted to RGB in the computer for editing when RGB is the desired output. If YUV is the desired output, and the video editing program supports YUV, there is no need to convert to RGB for internal processing. However, no matter which color space is used for editing, all data must be converted to RGB for screen display. See YUV, Adobe RGB, sRGB, color space and anaglyph 3D.


RGB Display and CMYK Printing
Display screens are RGB devices and have red, green and blue pixels. Printers are CMYK devices and use cyan, magenta, yellow and black inks. In theory, equal parts of cyan, magenta and yellow ink make black, but they tend to be muddy. Thus, black ink is used, making it a four color CMYK process (K for blacK). See CMYK.








RGB Color Conversions
Printing requires conversion from RGB to CMYK, and video editing requires conversion to and from RGB and YUV.
References in periodicals archive ?
3, in the RGB color model, each of the R, G and B components of a color image is referred to as a matrix, where m and n are the number of rows and the columns of a color matrix, and r, g and b are the values of R, G and B color matrixes, respectively.
2 presents the linear relationships between luminosity and intensity of the color components of the RGB color model derived from the rooftop profiling.
This intermediate property of RGB yellow is indicated as its spectral peak between those of G and R in the RGB color model (Smith, 1999).
He supplemented the more common, subtractive CMYK color model--the acronym referring to cyan, magenta, yellow, and key, or black--with the rarer additive RGB color model, which is premised on red, green, and blue.
The popular RGB color model corresponds most closely to the human vision.
The RGB color model is an additive color model in which red, green, and blue light are added together in various ways to reproduce a broad array of colors.
A RGB image is represented by three arrays of color numbers one for each of the color components of the RGB color model. In contrast, a GIF image is stored as two arrays.
Therefore, the RGB color model that assumed equal importance on the three components of Red, Green, and Blue does not meet the sensitivity of human visual perception and is not very suitable to be used for the sharpening purpose.
GlobalVision Color Inspection compares Pantone colors as well as references that use LAB, CMYK, and RGB color models. First, users select color points to compare against the printed component; then the software reports any estimated color differences beyond a defined threshold.