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The RGB color model for HTML was formally adopted as an Internet standard in HTML 3.2,[17] though it had been in use for some time before that. Initially, the limited color depth of most video hardware led to a limited co

An RGB triplet (r,g,b) represents the three-dimensional coordinate of the point of the given color within the cube or its faces or along its edges. This approach allows computations of the color similarity of two given RGB colors by simply calculating the distance between them: the shorter the distance, the higher the similarity. Out-of-gamut computations can also be performed this way.

The RGB color model for HTML was formally adopted as an Internet standard in HTML 3.2,[17] though it had been in use for some time before that. Initially, the limited color depth of most video hardware led to a limited color palette of 216 RGB colors, defined by the Netscape Color Cube. With the predominance of 24-bit displays, the use of the full 16.7 million colors of the HTML RGB color code no longer poses problems for most viewers.

The web-safe color palette consists of the 216 (63) combinations of red, green, and blue where each color can take one of six values (in hexadecimal): #00, #33, #66, #99, #CC or #FF (based on the 0 to 255 range for each value discussed above). These hexadecimal values = 0, 51, 102, 153, 204, 255 in decimal, which = 0%, 20%, 40%, 60%, 80%, 100% in ter

The web-safe color palette consists of the 216 (63) combinations of red, green, and blue where each color can take one of six values (in hexadecimal): #00, #33, #66, #99, #CC or #FF (based on the 0 to 255 range for each value discussed above). These hexadecimal values = 0, 51, 102, 153, 204, 255 in decimal, which = 0%, 20%, 40%, 60%, 80%, 100% in terms of intensity. This seems fine for splitting up 216 colors into a cube of dimension 6. However, lacking gamma correction, the perceived intensity on a standard 2.5 gamma CRT / LCD is only: 0%, 2%, 10%, 28%, 57%, 100%. See the actual web safe color palette for a visual confirmation that the majority of the colors produced are very dark.[18]

The syntax in CSS is:

rgb(#,#,#)

where # equals the proportion of red, green, and blue respectively. This syntax can be used after such selectors as "background-color:" or (for text) "color:".

Proper reproduction of colors, especially in professional environments, requires color management of all the devices involved in the production process, many of them using RGB. Color management results in several transparent conversions between device-independent and device-dependent color spaces (RGB and others, as CMYK for color printing) during a typical production cycle, in order to ensure color consistency throughout the process. Along with the creative processing, such interventions on digital images can damage the color accuracy and image detail, especially where the gamut is reduced. Professional digital devices and software tools allow for 48 bpp (bits per pixel) images to be manipulated (16 bits per channel), to minimize any such damage.

ICC-compliant applications, such as Adobe Photoshop, use either the Lab color space or the CIE 1931 color space as a Profile Connection Space when translating between color spaces.ICC-compliant applications, such as Adobe Photoshop, use either the Lab color space or the CIE 1931 color space as a Profile Connection Space when translating between color spaces.[19]

All luminancechrominance formats used in the different TV and video standards such as YIQ for NTSC, YUV for PAL, YDBDR for SECAM, and YPBPR for component video use color difference signals, by which RGB color images can be encoded for broadcasting/recording and later decoded into RGB again to display them. These intermediate formats were needed for compatibility with pre-existent black-and-white TV formats. Also, those color difference signals need lower data bandwidth compared to full RGB signals.

Similarly, current high-efficiency digital color image data compression schemes such as JPEG and MPEG store RGB color internally in YCBCR format, a digital luminance-chrominance format based on YPBPR. The use of YCBCR also allows computers to perform data compression schemes such as JPEG and MPEG store RGB color internally in YCBCR format, a digital luminance-chrominance format based on YPBPR. The use of YCBCR also allows computers to perform lossy subsampling with the chroma channels (typically to 4:2:2 or 4:1:1 ratios), which reduces the resultant file size.