GIMP tools - BDA

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RGB model
Colours are represented using two main colour models: CMYK and RGB. Images of raster
graphics are described by two key parameters: colour depth and dimensions. Colour
depth is the number of colours in a single pixel of a digital image 16 .
Now, the following numbers of colours are usually used:
a) 16 (one pixel is represented by 4 bits 17 )
b) 256 (one pixel is represented by 8 bits)
c) 16 million (one pixel is represented by 24 bits)
In the RGB colour model, colours are created by adding together three primary colours:
red, green and blue. These colours are used in video devices, scanners, monitors, digital
cameras.
The table below contains eight key colours and values of the colours that make them:
Colour Red Green Blue
Black 0 0 0
White 255 255 255
Red 255 0 0
Green 0 255 0
Blue 0 0 255
Yellow 255 255 0
Magenta 255 0 255
Cyan 0 255 255
The higher the resolution is, the deeper the colour you have.
Note!
When values of all colours coincide, one of the shades of grey is created. The lower the
values are, the darker grey you have. Higher values make a light grey shade.
Images of this model are not good for printing.
Grayscale
16 Also called Bit Depth, Image Mode.
17 There are several definitions. Here are three of them: 1) a basic unit of information used in the
theory of information. It represents the quantity of information received after learning which of
the two equally likely events has occurred; 2) one segment of the binary digit (0 or 1); 3) the
smallest unit of information in a computer, represented in one element of two states.