true colour

Also found in: Idioms.

true colour

A system where the red, green, and blue components of a colour are stored in display memory, as opposed to storing logical colours and using a colour palette to convert them to red, green, blue components.

The advantage of true colour over a palette is that it does not restrict the range of colours which can be displayed on screen simultaneously. For example, if eight bits are used to store each component of each pixel then a total of 2^24 (about 17 million) different colours can be displayed at once which would require a (very expensive) palette with 3 * 2^24 bytes (about 50 megabytes) of memory.

The disadvantage of true colour is that image transformations which would normally be done by changing the palette must be done to every pixel of the image which can be much slower.

Compare high colour.
This article is provided by FOLDOC - Free Online Dictionary of Computing (
References in classic literature ?
What Emma Haredale and Dolly would have done, or how long Miss Miggs, now that she had hoisted her true colours, would have gone on waving them before their astonished senses, it is impossible to tell.
In our profession we know something of human nature, and take my word for it, that the feller that came back to work out that shilling, will show himself one of these days in his true colours. He's a low thief, sir.
Then the great hour struck,[*] and every man showed himself in his true colours."
Littimer, rubbing his hands uneasily, 'which anybody might have supposed would have been, at all events, appreciated as a kind intention, then the young woman came out in her true colours. A more outrageous person I never did see.
Business development manager at Zeiss, Claire Martin, told 07 that the Clarus is an ultra-widefield camera that "uses true colour and it has a very high resolution whether you are looking in the peripheral area or whether you are looking in the central optic nerve head area."
However, under UV light it exhibits a brilliant true colour half tone image that can only be achieved with foil, and not on paper surfaces.
Icy blue eyes Dust the teal colour from the Avon True Colour Eyeshadow Quad in Arctic Goddess over the eyelids using a MAC 217 brush, blending the colour into the top of the brow.
Among the key product features of the GW Series include 5000:1 ultra high native contrast adding astonishing colour depth and definition to darkened, complex images with better subtlety and clarity; and True 8-bit colour performance rendering a total of 16.7 million colour shades with interpolated 24-bit true colour to deliver smoother and more stable transitions from one colour to the next.
The new FZ Omron Vision Sensor makes it possible to automate inspection of low contrast colour objects at high speed with reliable results by using true colour technology and intelligent cameras.
Not only offering the means to achieving differential gradations of colour and opacity, the process can also achieve true colour reproduction of photographs and complex graphics.