[mythtv-users] A Few Transcoder Questions

Patrick Reynolds reynolds at cs.duke.edu
Fri Apr 2 01:51:30 EST 2004

On Wed, 31 Mar 2004, Nowhere wrote:

> 1. When I got to setting / recording profiles there are two options.
> MPEG2 Encoders and Transcoders. MPEG2 Encoder I get and settings are
> fine, I have two PVR 250's .  Under the transcoders section there are
> TWO transcoders listed RTJPEG/MPEG4 and MPEG-2. I have no idea when I
> hit the "T" key which is being used. Since it replaces the episode when
> done recording, I would like to know before transcoding. I cant seem to
> find any settings anywhere to tell mythtv which transcoder to use.

The RTJPEG/MPEG4 and MPEG-2 entries refer to which format you're
transcoding _from_.  So configure the MPEG-2 entry to your liking.  It
will encode as either MPEG4 or RTJPEG -- even though its source is MPEG-2.

> 3. The one show I did transcode was much smaller in size (so I suspect
> RTJPEG/MPEG4 was used) but the video is very blocky now.

RTJPEG would be bigger, so it probably used MPEG4.  Raise the bitrate if
it's too blocky.  I find 2200 to be much too low.  4000 looks OK for me.
Ymmv -- with a cleaner signal, lower bitrates do better.

> 5. If I use MPEG2 as the transcoder, and I rename the extension to .mpg
> after transcoding, will it be SVCD compatible (assuming I have the
> resolution and such set correctly).

Afaik, no.  Use nuvexport.  Coming from MPEG-2, you may be able to use
avidemux or similar if SVCD is anything like DVD.  Search the archives for
DVD encoding.

> 6. If I hit "T" for several videos, are the queued? Or does it fire the
> transcoding off in parallel? (I assume queued...)

I think they're queued.  Running them in parallel would be slower in the
long run, because of disk and CPU contention.


More information about the mythtv-users mailing list