[mythtv-users] mythtv darkens dark scenes on video playback and on desktop

[Bill Williamson]

On Thu, Sep 10, 2009 at 1:16 PM, Dave Richardson <mythtv at derdev.com> wrote:
> I swear this to be true (!)...
>
> The Mythbuntu desktop and all video playback seems to darken on video
> playback that involves darker scenes.  It then brightens to what I regard
> as normal brightness when the scene has more color or brightness.
>
> For instance on the plain mythbuntu desktop (Gnome?) I use a dark theme.
> If there's nothing else being displayed, the screen is darkened by, say,
> 40%.  If I right click to open the mouse menu, or open a menu navigation,
> the whole screen brightens up again.
>
> It's kind of like that feature (that I hate) on car stereos that raises
> and lowers the audio level based upon the speed of the car.
>
> I've disabled all power saving options on my LCD HD TV.  Is there any
> chance there's a setting somewhere in mythbuntu, myth, or the nvidia
> driver that I don't know about that is causing this behavior?
>
> kit: mythbuntu 9.04, myth 0.21, ionitx a-u w/geforce 9400, nvidia driver
> 180 series (from their website a week ago), HDMI output.
>
> (Cable tv playback directly into the TV does not have this "feature".
>
> Thanks in advance!


Your tv has "contrast" set to "dynamic".  It likely doesn't do it for
the onboard cable tuner, but probably has it turned on for hdmi.'

It's not a power saving thing, it's so that they can lie and say the
TV has 328493248932:1 contrast ratio.

I actually keep it on for my TV as I watch with the lights off (it's
only on the tv in the bedroom) but I can see how it'd be annoying in a
lit room.