1.1 Glossary

This document uses the following terms:

ANSI character: An 8-bit Windows-1252 character set unit.

ARGB: A color space wherein each color is represented as a quad (A, R, G, B), where A represents the alpha (transparency) component, R represents the red component, G represents the green component, and B represents the blue component. The ARGB value is typically stored as a 32-bit integer, wherein the alpha channel is stored in the highest 8 bits and the blue value is stored in the lowest 8 bits.

AYCoCg: A color space in which each color is represented as a quad (A, Y, Co, Cg), where A represents the alpha (transparency) component, Y represents the luma (intensity) component, and Co and Cg represent the two chrominance (color) components orange and green, respectively.

color plane: A two-dimensional surface containing a collection of values that represent a single component of the ARGB or AYCoCg color space.

color space: A mapping of color components to a multidimensional coordinate system. The number of dimensions is generally two, three, or four. For example, if colors are expressed as a combination of the three components red, green, and blue, a three-dimensional space is sufficient to describe all possible colors. If transparency is considered one of the components of an RGB color, four dimensions are appropriate.

little-endian: Multiple-byte values that are byte-ordered with the least significant byte stored in the memory location with the lowest address.

run-length encoding (RLE): A form of data compression in which repeated values are represented by a count and a single instance of the value.

MAY, SHOULD, MUST, SHOULD NOT, MUST NOT: These terms (in all caps) are used as defined in [RFC2119]. All statements of optional behavior use either MAY, SHOULD, or SHOULD NOT.