All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Ville Syrjälä" <syrjala@sci.fi>
To: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: spock@gentoo.org,
	Linux-fbdev-devel <linux-fbdev-devel@lists.sourceforge.net>
Subject: Re: Fix 8bpp RGB fields length
Date: Mon, 2 Mar 2009 15:02:02 +0200	[thread overview]
Message-ID: <20090302130202.GA6298@sci.fi> (raw)
In-Reply-To: <20090301215556.8631c63c.krzysztof.h1@poczta.fm>

On Sun, Mar 01, 2009 at 09:55:56PM +0100, Krzysztof Helt wrote:
> Hi,
> 
> I found that some fbdev drivers set RGB field's lengths incorrectly
> to 6 bits. This is incorrect as the field's length says how many bits
> has a color index when using color palette (6 bits = 64 colors).

A slight omission in the fbdev API I suppose since the LUT entries are
nearly always 3*8bits wide. VGA being the exception.

> Fix this error in uvesafb by dropping DAC switching to 8 bits 
> completely. Advantage of this approach is making the driver shorter,
> disadvantage is that some color fidelity is lost.

I don't see much point in dropping this. It would reduce the image
quality and it looks like after your first fix this code would amount
to less than a dozen lines. But not my call anyway.

-- 
Ville Syrjälä
syrjala@sci.fi
http://www.sci.fi/~syrjala/

------------------------------------------------------------------------------
Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA
-OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise
-Strategies to boost innovation and cut costs with open source participation
-Receive a $600 discount off the registration fee with the source code: SFAD
http://p.sf.net/sfu/XcvMzF8H

  reply	other threads:[~2009-03-02 13:02 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-01 20:55 Fix 8bpp RGB fields length Krzysztof Helt
2009-03-02 13:02 ` Ville Syrjälä [this message]
2009-03-02 17:02   ` Krzysztof Helt
2009-03-02 17:40     ` Ville Syrjälä
2009-03-29 19:14     ` Michal Januszewski
2009-03-29 19:26       ` Geert Uytterhoeven
2009-03-29 21:18         ` Ville Syrjälä

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20090302130202.GA6298@sci.fi \
    --to=syrjala@sci.fi \
    --cc=krzysztof.h1@poczta.fm \
    --cc=linux-fbdev-devel@lists.sourceforge.net \
    --cc=spock@gentoo.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.