[mythtv-users] Can you play 720p mpeg 4 files?

[Brad Templeton]

Recently I was doing some experiments transcoding HDTV shows using
myths internal transcoder.  I have been able to do it myself with
mencoder but you don't get cutlists when you do this.

My first experiment had surprisingly bad results.  I transcoded a half
hour 720p program.   The transcoder can be set to adjust the bitrate
with the number of pixels.  That turns out to be not the best ratio
since 720p, while it has 3 times the pixels of the 640x480 reference
size, should not really go at 3 times the bitrate for comparable quality.

Note I was transcoding 720p to 720p -- no drop in size, just a convert
to mp4.

However, to my surprise the resulting file, aside from being no smaller
due to the higher bitrate, also was too much for myth or mencoder to
play.  Myth plays it back dropping frames like crazy, even on a 3ghz P4,
and even though it shows 60% idle.  Same result on an Athlon-3000 -- even
worse, but still not saturating the CPU by any stretch.

Any similar experiences or thoughts?   My hand transcodes, usually of
1080i programs to 1280x540p, tended to be just fine.