[mythtv-users] Higher-quality archive to DVD (interlacing)

[John Pilkington]

On 11/05/15 22:10, Will Dormann wrote:
> Hi folks,
>
> I've recently revisited the concept of burning a MythTV-recorded program
> to DVD.   In this case it was a long (just over 2 hours) recording.
>
> The first thing I noticed was that mythburn.py would stop with a "MySQL
> server has gone away" error after encoding the recording with ffmpeg.
> My hunch here is that mythburn.py opens a database connection at the
> beginning and re-uses that connection for the rest of its operation.
> Since my mythtv box is quite anemic (Atom/ION), it can be over 12 hours
> for a 2-pass encoding of an HD h.264 recording.   My workaround was in
> my /etc/mysql/my.cnf to specify:
>
> connect_timeout         = 100000
> wait_timeout            = 100000
>
> I'm not certain if both are required though.
>
>
> The other thing is that cutlists still don't work with HD-PVR (h.264)
> recordings.  So I'm using my old patch still:
> http://lists.mythtv.org/pipermail/mythtv-users/2014-May/363676.html
>
>
> Now on to the issue in the subject.  Due to a glitch in the recording
> itself, the DVD that mytharchive produced a DVD that was only about 48
> minutes.  So I investigated an alternative: avstodvd
> <http://sourceforge.net/projects/avstodvd/>
>
> When comparing the mytharchive-produced vs. the avstodvd-produced
> output, it became clear that the former was deinterlaced and the latter
> was interlaced.  My source is 1080i, and the ffmpeg route just
> re-encodes it which looks to deinterlace it.   While the deinterlacing
> seems to look good, the outcome is that the smoothness suffers (to the
> picky eye at least).    A 1080i recording displays 59.94 pictures
> (frames) per second.   The ffmpeg route throws away half of that
> smoothness to end up with a DVD-compatible 29.97 fps.
>
> Now consider the avstodvd scenario.  It uses avisynth split the fields,
> resize, and then re-interlace the fields together.  The end result is an
> interlaced DVD that has 59.94 pictures per second.
>
> I'm not sure if there's a GNU/Linux equivalent of avisynth is, but I'm
> wondering if anybody has put any thought into some way of improving the
> quality of produced DVDs through the use of interlacing (when
> appropriate)?    Or is the concept of burning recordings to DVD archaic
> enough that it's not worth the effort?
>
>
> -WD

It seems to me that DVDs still provide an inexpensive way of carrying 
small collections of recordings that can be played on generic hardware. 
But I suspect that many players now come with 'enhancements' in various 
flavours that might not all be compatible with specific forms of 
'enhanced' DVD; YMMV?

John P