[vdr] Epia tv-out methods (was: EPIA SP + budget hardware
laz at club-burniston.co.uk
Thu Mar 10 12:49:38 CET 2005
On Thu, 2005-03-10 at 11:21 +0100, Nicolas Huillard wrote:
> Your summary is good.
Cool: it's quite difficult to get answers to things I was looking for!
> What I'd say (I still didn't switch back to softdevice, so I'm not
> up-to-date wrt the latest release) :
> * use X / vdr-xine / XvMC when you have a regular PC (mouse, keyboard,
> etc.) : this is actually necessary to run Xine, VDR, X, etc. Xine needs
> 200MB memory and X approx. 40MB (a lot is shared, and works with 256MB
> RAM). Add that to the 40MB for VDR...
> * use softdevice / DirectFB / software decoding if you have a STB-like
> HTPC (no keyboard, no mouse, just the remote) : runvdr will handle
> running VDR *and* the display, restarting, etc. Software decoding is not
> a problem for your 1.2GHz processor (indeed, less a problem than running
> Xine separately)
This is probably the route I will aim for: my current box has a dxr3 for
output but it does have X for doing a bit of coding in front of the
tele'! I can live without that, though.
> Subscribe to the softdevice mailing-list (softdevice-devel at berlios.de).
> There are interesting developments and skilled developers there.
Doing it now...
> The subject of you post mentions "tv-out" : this is a great subject, and
> you should really consider the output quality in your planning.
> The TV-encoder on the EPIA board (VT162x) is driven by data tables,
> present in the frame-buffer kernel module for the CLE266, and also
> present in the X driver for the CLE266. These tables contains many
> parameters for the video output (PAL, NTSC, anti-flicker, etc.), and
> come from VIA. The parameters are actually far less than optimal (in the
> versions I have, dated a few months back) : the image has large black
> borders around (each 4 sides), is largely anti-flickered, thus blurred, etc.
> This lead to a huge loss in resolution. 720x576 should be full PAL
> display, but is actually far less with these tables. Ville Syrjälä from
> the DirectFB ML sent me the doc for the VT162x encoders, but I don't
> have time to dig into better parameters. I can send it if anyone want to
> improve that.
I saw some posts about that when I was looking for info!
> The alternate TV-out method is to generate SCART RVB signal from the VGA
> output of the board, which should be good, if one can find the correct
> timing for the frame-buffer driver and/or X driver.
This is another option I was going to look into. Presumably Epias can't
put out a composite sync signal so I would have to combine the
horizontal and vertical syncs. Component RGB output from my stand-alone
DVD player is noticeably better than S-video output from it. I have seen
modelines for doing this with a PAL or NTSC signal but have never got
around to trying it. I'm hoping that is these boards can drive a PAL or
NTSC output directly, the same sync signals are available at the SVGA
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