question: How do pixels know when and what color to display?
comment: They don't. The computer sets the pixel to whatever color is needs. I'm not quite sure why you think a pixel needs to "know" anything. Could you perhaps explain how you arrived at that idea? I should be able to better explain what's going on then.
passages: Windows Color System features a "Color Infrastructure and Translation Engine" (CITE) at its core. It is backed up by a color processing pipeline that supports bit-depths more than 32 bits per pixel, multiple color channels (more than three), alternative color spaces and high dynamic range coloring, using a technology named "Kyuanos" developed by Canon. The color processing pipeline allows device developers to add their own gamut mapping algorithm into the pipeline to customize the color response of the device. The new pipeline also supports floating point calculations to minimize round-off errors, which are inherent in integer processing. Once the color pipeline finishes processing the colors, the CITE engine applies a color translation according to a color profile, specific to a device to ensure the output color matches to what is expected.
   Section::::Information flow and output distortion.
  
  Input data can come from device sources like digital cameras, image scanners or any other measuring devices. Those inputs can be either monochrome (in which case only the response curve needs to be calibrated, though in a few select cases one must also specify the color or spectral power distribution that that single channel corresponds to) or specified in multidimensional color - most commonly in the three channel RGB model. Input data is in most cases calibrated against a profile connection space (PCS).
   Section::::Color separation.
  
  There are several main types of color image sensors, differing by the type of color-separation mechanism:
   In the output stage when exporting to a viewing device such as a CRT or LCD screen or a digital projector, the computer sends a signal to the computer's graphic card in the form RGB [Red,Green,Blue]. The dataset [255,0,0] signals only a device instruction, not a specific color. This instruction [R,G,B]=[255,0,0] then causes the connected display to show Red at the maximum achievable brightness [255], while the Green and Blue components of the display remain dark [0]. The resultant color being displayed, however, depends on two main factors:
   Some LCDs may use temporal dithering to achieve a similar effect. By alternating each pixel's color value rapidly between two approximate colors in the panel's color space (also known as Frame Rate Control), a display panel which natively supports only 18-bit color (6 bits per channel) can represent a 24-bit "true" color image (8 bits per channel).
   Additive color models are applied in the design and testing of electronic displays that are used to render realistic images containing diverse sets of color using phosphors that emit light of a limited set of primary colors. Examination with a sufficiently powerful magnifying lens will reveal that each pixel in CRT, LCD, and most other types of color video displays is composed of red, green, and blue light emitting phosphors which appear as a variety of single colors when viewed from a normal distance.
   After this the data is often circulated in the system translated into a working space RGB for viewing and editing.
   There are 2 types of monitors, they are "Monochrome & Colored Monitors". "Monochrome" monitors actually display two colors, one for the foreground and one for the background. The colors can be black and white, green and black, or amber and black. The "Colored Monitor" is a display device capable of displaying many colors. The Color monitors can display anywhere from 16 to over 1 million different colors.
  
  Section::::Display devices about-.:Types of Display (Monitor).:Monochrome Display.
   Color management
  
  In digital imaging systems, color management (or colour management) is the controlled conversion between the color representations of various devices, such as image scanners, digital cameras, monitors, TV screens, film printers, computer printers, offset presses, and corresponding media.
   Parts of this technology are implemented in the operating system (OS), helper libraries, the application, and devices. A cross-platform view of color management is the use of an ICC-compatible color management system. The International Color Consortium (ICC) is an industry consortium that has defined:
  
  BULLET::::- An open standard for a "Color Matching Module" (CMM) at the OS level
  
  BULLET::::- color profiles for:
  
  BULLET::::- Devices, including devicelink-profiles that represent a complete color transformation from source device to target device
  
  BULLET::::- "Working spaces", the color spaces in which color data is meant to be manipulated
   For creating a scanner profile it needs a target source, such as an IT8-target, an original with many small color fields, which was measured by the developer with a photometer. The scanner reads this original and compares the scanned color values with the target's reference values. Taking the differences of these values into account an ICC profile is created, which relates the device specific color space (RGB color space) to a device independent color space (L*a*b* color space). Thus, the scanner is able to output with color fidelity to what it reads.
  
  Section::::Calibration techniques and procedures.:Display.
   Color scanners typically read RGB (red-green-blue color) data from the array. This data is then processed with some proprietary algorithm to correct for different exposure conditions, and sent to the computer via the device's input/output interface (usually USB, previous to which was SCSI or bidirectional parallel port in older units).
  
  Color depth varies depending on the scanning array characteristics, but is usually at least 24 bits. High quality models have 36-48 bits of color depth.
   For multi-coloured printing, the image is broken up into multiple layers representing each of the spot colors or the CMYK process colors, this may be split manually by the designer or separated by software in the imagesetter itself. Each color is made into its own piece of film and plate, there can be 12 or more colors used in a single production run, however 1-6 colors are typical.
   Section::::Comparison to traditional pixel arrays.
   Color is also supported using the character, followed by a number referring to one of a number of color registers, which varied from device to device. The colors in the registers are defined using either RGB or HLS values in a peculiar DEC format. To create a color image on a printer, a line of sixels is sent several times, each representing a single bitplane from the register-based colors on the terminals (normally 2 or 4 bits). Since the capabilities of the hardware vary widely, a color sixel drawing can only be output to targeted devices. Non-graphics terminals generally silently ignore sixel escape sequences.
   Hqx uses the YUV color space to calculate color differences, so that differences in brightness is weighted higher to mimic human perception. It is possible to use a look-up table for the color space conversion if the source image is 16 bit per pixel.
   An array of elements that all reflect the same color when turned on produces a monochromatic display, for example black and red (in this example using IMOD elements that reflect red light when "on"). As each element reflects only a certain amount of light, grouping several elements of the same color together as subpixels allows different brightness levels for a pixel based on how many elements are reflective at a particular time.
   Color on the Apple II series uses a quirk of the NTSC television signal standard, which made color display relatively easy and inexpensive to implement. The original NTSC television signal specification was black-and-white. Color was added on later by adding a 3.58-MHz subcarrier signal that was partially ignored by black-and-white TV sets. Color is encoded based on the "phase" of this signal in relation to a reference "color burst" signal. The result is that the position, size, and intensity of a series of pulses define color information. These pulses can translate into "pixels" on the computer screen, with the possibility of exploiting composite artifact colors.
   For visually acceptable results, it is necessary (and almost sufficient) to provide three samples ("color channels") for each pixel, which are interpreted as coordinates in some color space. The RGB color space is commonly used in computer displays, but other spaces such as YCbCr, HSV, and are often used in other contexts. A color image has three values (or channels) per pixel and they measure the intensity and chrominance of light. The actual information stored in the digital image data is the brightness information in each spectral band.
  
  Section::::Color image representation.
   Section::::History.:Additive color.
  
  Creating colors by mixing colored lights (usually red, green and blue) in various proportions is the additive method of color reproduction. LCD, LED, plasma and CRT (picture tube) color video displays all use this method. If one of these displays is examined with a sufficiently strong magnifier, it will be seen that each pixel is actually composed of red, green and blue sub-pixels which blend at normal viewing distances, reproducing a wide range of colors as well as white and shades of gray. This is also known as the RGB color model.
  
  Section::::History.:Subtractive color.
   BULLET::::1. Characterize. Every color-managed device requires a personalized table, or "color profile," which characterizes the color response of that particular device.
  
  BULLET::::2. Standardize. Each color profile describes these colors relative to a standardized set of reference colors (the "Profile Connection Space").
  
  BULLET::::3. Translate. Color-managed software then uses these standardized profiles to translate color from one device to another. This is usually performed by a color management module (CMM).
  
  Section::::Hardware.
  
  Section::::Hardware.:Characterization.
   BULLET::::1. Apply the first test pattern to the electrical interface of the display under test and wait until the optical response has settled to a stable steady state,
  
  BULLET::::2. Measure the luminance and/or the chromaticity of the first test pattern and record the result,
  
  BULLET::::3. Apply the second test pattern to the electrical interface of the display under test and wait until the optical response has settled to a stable steady state,
  
  BULLET::::4. Measure the luminance and/or the chromaticity of the second test pattern and record the result,
   Every pixel from the secret image is encoded into multiple subpixels in each share image using a matrix to determine the color of the pixels. 
  
  In the (2,N) case a white pixel in the secret image is encoded using a matrix from the following set, where each row gives the subpixel pattern for one of the components:
  
  While a black pixel in the secret image is encoded using a matrix from the following set:
   During digital image processing each pixel can be represented in the computer memory or interface hardware (for example, a "graphics card") as binary values for the red, green, and blue color components. When properly managed, these values are converted into intensities or voltages via gamma correction to correct the inherent nonlinearity of some devices, such that the intended intensities are reproduced on the display.
  
  The Quattron released by Sharp uses RGB color and adds yellow as a sub-pixel, supposedly allowing an increase in the number of available colors.
  
  Section::::RGB devices.:RGB and displays.:Video electronics.
   For example, the Bayer filter (shown to the right) gives information about the intensity of light in red, green, and blue (RGB) wavelength regions. The raw image data captured by the image sensor is then converted to a full-color image (with intensities of all three primary colors represented at each pixel) by a demosaicing algorithm which is tailored for each type of color filter.
  
presuppositions: Pixels know when and what color to display. A pixel knows what color it should be.
corrections: Pixels don't "know" - the computer sets the pixel to whatever color is needed. The computer controls pixel color.
raw_presuppositions: Pixels know when and what color to display. A pixel knows what color it should be.
raw_corrections: Pixels don't "know" - the computer sets the pixel to whatever color is needed. The computer controls pixel color.