[mythtv] nuv formats for mpeg4? mythtranscode?
subbyz at kinison.puremagic.com
Tue Mar 20 00:45:49 UTC 2007
I've been doing a lot of looking for something to allow conversion of
already transcoded (from mpeg2 to mpeg4 format) recordings into a plain-jane
avi container for playing on other platforms, without having to reencode and
incur another level of quality loss.
Unfortunately, the only thing I've found that looks like it fills this need
is nuvtools nuv2avi, which has some problems that I won't go into here since
they are unrelated to mythtv. I'm surprised more people aren't concerned
with having to go through another full transcode and associated generational
loss to get the recordings out of .nuv format.
I've read on the wiki that the NUV container is used internally to Myth to
solve sync issues between the audio and video. I understand why that might
be necessary for RTJPEG recordings, but am not clear on why that is
necessary for mpeg4 recordings, wether they are transcoded or not.
So, here's my questions: Is NUV format still necessary for mpeg4 original
or transcoded recordings? Could the .nuv container be replaced internally
to make the recordings more compatible with other systems without
functionality loss within mythtv? Is the nuv container for mpeg4 just an
artifact of that being the way it was originally done for RTJPEG, and an
attempt to keep the container format consistent with the older format, or
are there still technical reasons for keeping mpeg4 in the non-standard nuv
As a semi-related question, I see that mythtranscode has the --mpeg2 option
for what I'm assuming is a non-lossy transcode (except for the GOP's after
cutpoints). Is there anyone working towards doing the same thing for mpeg4?
Has there been interest in such a feature?
More information about the mythtv-dev