[mythtv] Any single-board solutions?

Stephen Davies mythtv-dev@snowman.net
Fri, 13 Sep 2002 18:21:20 +0100 (BST)


On Fri, 13 Sep 2002, Grant Taylor wrote:

>  - Dual CPU.  The overall quantity of data sloshing about can be
>    greatly reduced by using the mpeg4 code, and it looks like that
>    will only be full-featured (particularly for the forthcoming pip
>    features) when there is substantially more CPU available.  Mythtv's
>    coder/player threads won't split the work optimally in two, but it
>    should still work out better.

My box currently uses mpeg1 format (not with mythtv).  It captures and
encodes to mpeg1 using about 20% of my Athlon 1.13GHz CPU.  Playback
(mplayer) is very light (<5%).  I generally capture at 352x288.  I can
capture two sources at once at that resolution, whilst playing back one or
two at the same time.

CPU isn't a problem for 2 simultaneous 720x576 captures, but I seem to hit
PCI bus latency problems with that much data on the bus.

Disk throughput is no problem because the mpeg1 gives high compression - I
generally capture at around 1.5GB per hour.

mpeg1 is quite a bit lighter CPU-wise than mpeg4.  I'd suggest mythtv
should experiment with mpeg1.

A second advantage is its simpler to get from that the (S)VCD format
disks.

Steve