[mythtv-users] DVI v. Component
papenfuss at juneau.me.vt.edu
Fri Aug 13 07:40:59 EDT 2004
> Hey, Cory: which make and model of funky transcoder box did you pick?
I built one using an AD724 chip that will modulate an appropriate VGA
signal (15.7kHz/30Hz/interlaced) into NTSC composite or S-VID. I didn't do
much else than what the other homebrew designs on the 'net do. Quality is
outstanding... better than I've ever seen out of the mediocre-quality TVOUT
cards I've tried. The only problem is a slight "tearing" of mythtv ivtv
records (probably from vsync beat frequencies). Turning on kerneldeint greatly
I was originally planning on making a "swiss-army-trancoder," that
would take VGA in and output buffered VGA, composite, s-vid, and component.
You would (of course) have to send out a modeline that's compatible with
anything that you were going to use (no scanline conversion). I just did a
prototype with the hardest part (AD724), and I never got around to adding the
few additional components. Part of the reason is that from what I understand,
component HDTV uses bi-level sync (at least for interlaced modes), rather than
the more TTL-like on VGA and NTSC. To build the VGA->component part of the
transcoder would then require some more work. The TV I'm using only supports
480i on its component anyway.
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