[mythtv-users] Minimizing bandwidth with MPEG-4
andy at kuan.net
Wed Mar 31 10:52:38 EST 2004
I've been trying to come up with encoder settings for MPEG-4 that
provide the lowest possible bandwidth utilization. This is in the hopes
of being able to watch (grainy) TV on my desktop at work. It _almost_
runs smoothly for me right now.
My current settings are 160x160 MPEG-4 at 100kbps, max qual 2, min qual
15, qual diff 3, 4MV and hi-qual checked, MP3 sampled at 32000 at a
quality of 9. These settings will produce a 50M file for a 30 minute
show. That's around 200kbps which is 2/3 of the upstream capacity on my
cable modem (which makes me wonder why it isn't 100kbps as set -- ah
well). I tried watching some baseball from the office yesterday and
experienced momentary drop outs (~1-2 sec) every 10 seconds or so -- so
I know I'm close. I figure I'll never get the full 300kbps upstream from
my cable modem, so my target should be around 150kbps for my encoding
I don't believe the 4MV and hi-qual MPEG-4 settings will make a
difference. That leaves changes to the max qual, min qual, and qual diff
settings for MPEG-4 and the audio settings. Unfortunately I haven't seen
any documentation whatsoever on how to adjust those MPEG-4 quality
settings (except for warnings _not_ to touch the settings) and there
isn't a control to alter the bitrate of the MP3 audio.
Has anyone else attempted this or have any suggestions? Thanks!
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