[mythtv-users] Issues with new DVB card (aspect ratio and interlacing)

[Marlor LPE]

> > 1. I can't use filters such as "kerneldeint" when
> > encoding. This seems strange, since MythTV is
> > encoding the stream to MPEG-4, just as it did 
> > with the analogue card.
> 
> I dont think its being deinterlaced because with
> DVB you are capturing the raw data, not frame 
> grabbing.

As far as I can see MythTV is encoding this raw data
straight to MPEG-4 (or RTJpeg). It would be nice if
there was some way to deinterlace during this encoding
process, as the OS X version of MythTV is extremely
inefficient when it comes to zooming or deinterlacing
during playback (it results in >3x the CPU
utilization).

The MythTV docs actually mention the limitations for
filtering with DVB: 
"These [filters] may be used when encoding in software
(MPEG-4, RTjpeg) but do not apply when using a capture
card with hardware encoding such as those supported by
the ivtv driver, DVB, HDTV or MJPEG cards". 
However, in my case, I am still encoding the video
stream in software, as I don't believe that my DVB
card has a hardware MPEG encoder built in.

> > 2. The aspect ratio is stuck at 16:9. This means
> > that when a show is broadcast in 4:3, there are 
> > black bars at the top, bottom and sides.
> 
> Check your mythfrontend settings to make sure you
> don't have override aspect ratio on.

As Ben de Luca noted, all broadcasts (even those with
a 4:3 aspect ratio) are broadcast in 16:9 here in
Australia. AFAIK, our digital set-top-boxes simply
zoom these to 4:3 when the "aspect" button is pressed
on the remote. It would be great if there is a way to
do this on the server side (via transcoding or via the
recording filter chain), since the Mac mini chokes
when trying to do it (and the XBox struggles a bit too).

Find local movie times and trailers on Yahoo! Movies.
http://au.movies.yahoo.com