Glossary for Geospatial Science

  Technical vocabulary defined by MicroImages

book Glossary

5-5-5 composite color conversion method:  16-bit color data uses 15 of the 16 bits to store the color intensity information: 5 bits to represent the intensity level for red, 5 bits for green, and 5 bits for blue (the 16th bit is typically unused).  With this scheme (32 possible levels for each color), each cell in a 16-bit raster can take any one of 32,768 possible colors.  Therefore, display boards that handle 16-bit color display data do not use color tables, since they have no need to map all the actually occurring colors into a limited set of 256 display colors.  When TNTmips displays three 8-bit raster objects that are used as an RGB set on 16-bit devices, it only needs to scale each 8-bit value into a 5-bit range.  (See also: color map, RGB.)