[mythtv-users] Suggested Encoding Rates

[Brad Templeton]

On Fri, Apr 29, 2005 at 12:20:00AM -0400, Donavan Stanley wrote:
> On 4/28/05, Alexander Varakin <avarakin at optonline.net> wrote:
> > Quality of PVR-?50 hardware encoder is very poor and it requires very high bit
> > rates for decent quality (about 6Mb/s).
> > Software MPEG2 encoders are much better, in Windows world CCE and TmpGenc are
> > very good(they can also run on Linux with wine). On linux mpeg2enc is also
> > very good.
> > I always reencode using software encoder.
> 
> If you're reencoding already encoded files it's too late.

To some extent.  But I think if you record 720x480 at a high bitrate (8mbit)
on your pvr-250, you can then reduce that to something lesser like 480x480
mpeg4 without doing too much worse than having done it from the raw.

Trying to go to the same resolution or not using a nice high bitrate
for the source would be bad news.  If, however, you plan to transcode
immediately, you might as well use a very high bit rate on the source
encoding to remove artifacts from the 1st step, it won't cost you anything
since the file is vanishing pretty soon.

This could make sense on a machine with not enough cpu to software encode
mp4 in real time (or not wanting to spare the cpu to leave it available for
watching.)

If you have the cpu to record mp4 in real time I suppose it makes more
sense to get a good raw capture card and do that, but it seems you
might not be able to do things like play HDTV and encode mp4 sdtv at
the same time even on a very fast system.