Re: Determine brightness of colour/Convert to GrayLevel
- To: mathgroup at smc.vnet.net
- Subject: [mg89509] Re: [mg89485] Determine brightness of colour/Convert to GrayLevel
- From: Carl Woll <carlw at wolfram.com>
- Date: Wed, 11 Jun 2008 03:19:12 -0400 (EDT)
- References: <200806101114.HAA18927@smc.vnet.net>
Szabolcs Horvát wrote: >Colours have several representations, such as RGBColor, CMYKColor, >GrayLevel, etc. > >Is there a way to convert between these representations? More >specifically is there a way to convert a colour to GrayLevel? I would >like to determine the "brightness" of a colour to decide whether to >display text in black or in white on top of it. > >Also, is there a way to convert a colour to some canonical >representation? A workaround I found is Lighter[colour, 0], which >converts to RGBColor, but I was hoping that there exists a function >meant specifically for conversion (and not >blending/lightening/darkening). > > Try ToColor: ?ToColor ToColor[color, form] converts color to form if form is GrayLevel, RGBColor or CMYKColor. Otherwise form[color] is evaluated and the result \ is expected to be a valid color directive. Carl Woll
- References:
- Determine brightness of colour/Convert to GrayLevel
- From: "Szabolcs HorvÃt" <szhorvat@gmail.com>
- Determine brightness of colour/Convert to GrayLevel