From: Lars Magne Ingebrigtsen <larsi@gnus.org>
To: ding@gnus.org
Subject: Re: Colour manipulation
Date: Sun, 21 Nov 2010 20:02:33 +0100 [thread overview]
Message-ID: <m3lj4mijp2.fsf@quimbies.gnus.org> (raw)
In-Reply-To: <8739quh5gk.fsf@keller.adm.naquadah.org>
Julien Danjou <julien@danjou.info> writes:
>> To bikeshed a bit, color.el is kinda very general name. Perhaps
>> color-calc.el or something would be better...
color-lab.el would be punnier.
>> My use case would be that I have a set background colour (eg., "black"),
>> and then the CSS says "text-color: blue". I then want to modify the
>> latter to be a colour that is visible enough to read. How would I do
>> that?
>
> Hum the easiest way would be to convert RGB to Lab and then change L, a
> or b.
>
> To have a good understanding of how colors are represented in Lab, just
> take a look at the Wikipedia[1] page, the image are pretty explicit.
I'm always interested in avoiding learning new things. :-)
> There's no easy way to know by how much you should increase L, a or b,
> or what would be the best choice.
>
> FWIW L is always between 0 and 100, and there's a good chance that just
> changing it to 0 or 100 (depending on the other color L value) would
> give for sure a good result. One has to try.
It's all Greek to me...
--
(domestic pets only, the antidote for overdose, milk.)
larsi@gnus.org * Lars Magne Ingebrigtsen
next prev parent reply other threads:[~2010-11-21 19:02 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <E1PArgx-0006dS-00@quimby.gnus.org>
2010-10-26 23:58 ` [gnus git] branch master updated: =1= shr.el (shr-tag-div): Added Lars Magne Ingebrigtsen
2010-10-27 0:15 ` Katsumi Yamaoka
2010-10-27 0:22 ` Katsumi Yamaoka
2010-10-27 0:28 ` Lars Magne Ingebrigtsen
2010-10-27 0:43 ` Katsumi Yamaoka
2010-10-27 18:06 ` Ted Zlatanov
2010-10-29 23:18 ` Lars Magne Ingebrigtsen
2010-11-09 22:25 ` Ted Zlatanov
2010-11-09 22:47 ` Lars Magne Ingebrigtsen
2010-11-09 23:02 ` Steinar Bang
2010-11-10 9:54 ` Julien Danjou
2010-11-10 17:49 ` Colourspace (was: [gnus git] branch master updated: =1= shr.el (shr-tag-div): Added.) Lars Magne Ingebrigtsen
2010-11-10 19:09 ` Colourspace Julien Danjou
2010-11-10 19:44 ` Colourspace Ted Zlatanov
2010-11-10 19:56 ` Colourspace Julien Danjou
2010-11-10 20:22 ` ELPA and Gnus (was: Colourspace) Ted Zlatanov
2010-11-10 20:48 ` ELPA and Gnus Lars Magne Ingebrigtsen
2010-11-10 21:23 ` Ted Zlatanov
2010-11-10 21:32 ` Lars Magne Ingebrigtsen
2010-11-11 13:19 ` Ted Zlatanov
2010-11-14 16:07 ` Lars Magne Ingebrigtsen
2010-11-15 15:43 ` Julien Danjou
2010-11-11 9:06 ` Julien Danjou
2010-11-14 16:07 ` Lars Magne Ingebrigtsen
2010-11-10 20:48 ` Colourspace Lars Magne Ingebrigtsen
2010-11-10 20:55 ` Colourspace Lars Magne Ingebrigtsen
2010-11-11 8:59 ` Colourspace Julien Danjou
2010-11-18 18:49 ` Colourspace Ted Zlatanov
2010-11-10 13:14 ` [gnus git] branch master updated: =1= shr.el (shr-tag-div): Added Ted Zlatanov
2010-11-19 16:13 ` Julien Danjou
2010-11-21 4:40 ` Lars Magne Ingebrigtsen
2010-11-21 13:55 ` Julien Danjou
2010-11-21 18:38 ` Colour manipulation (was: [gnus git] branch master updated: =1= shr.el (shr-tag-div): Added.) Lars Magne Ingebrigtsen
2010-11-21 18:55 ` Colour manipulation Julien Danjou
2010-11-21 19:02 ` Lars Magne Ingebrigtsen [this message]
2010-11-21 19:26 ` Julien Danjou
2010-11-21 19:42 ` Lars Magne Ingebrigtsen
2010-11-22 14:49 ` Julien Danjou
2010-11-24 2:27 ` Katsumi Yamaoka
2010-11-24 5:45 ` Katsumi Yamaoka
2010-11-24 6:39 ` Lars Magne Ingebrigtsen
2010-11-24 8:43 ` Julien Danjou
2010-11-24 20:37 ` Lars Magne Ingebrigtsen
2010-11-24 20:48 ` Lars Magne Ingebrigtsen
2010-11-24 21:18 ` Julien Danjou
2010-11-24 21:27 ` Lars Magne Ingebrigtsen
2010-11-24 8:52 ` Julien Danjou
2010-11-24 6:39 ` Lars Magne Ingebrigtsen
2010-11-24 8:37 ` Julien Danjou
2010-11-22 15:37 ` Julien Danjou
2010-11-22 15:59 ` Lars Magne Ingebrigtsen
2010-11-23 1:38 ` Lars Magne Ingebrigtsen
2010-11-23 9:15 ` Julien Danjou
2010-11-23 23:50 ` Lars Magne Ingebrigtsen
2010-11-23 9:48 ` Julien Danjou
2010-11-23 23:52 ` Lars Magne Ingebrigtsen
2010-11-21 19:57 ` Frank Schmitt
2010-11-22 19:47 ` Ted Zlatanov
2010-11-23 9:10 ` Julien Danjou
2010-11-23 14:52 ` Ted Zlatanov
2010-11-23 15:54 ` Julien Danjou
2010-11-23 16:15 ` Ted Zlatanov
2010-11-23 18:32 ` Colour blindness correction (was: Colour manipulation) Julien Danjou
2010-11-23 23:50 ` Colour manipulation Lars Magne Ingebrigtsen
2010-11-24 8:32 ` Julien Danjou
2010-11-26 20:17 ` Adam Sjøgren
2010-11-24 1:09 ` Greg Troxel
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