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webwonk
18th June 2007, 17:47
I've search about and found some info - but nothing that directly addresses live encoding:

What are some recommended settings for encoding live (off an Osprey-230 card a/v) if I want to do 320x240 h.264/faac rtp streaming to a single source?

I'm thinking:
CABAC = on
Loop Filter = on (-2,0)
Ref = 4
--aq-strength 0.5
--no-fast-pskip
H.264: 320x240 @ 29.97 (de-int at source) fps @ 450 kbs?
FAAC: stereo 48 kHz @ 96 kbs

The other thing I need *real* help with is a recommendation of a live encoder. I believe I can use VLC to encode & stream - correct?

Dark Shikari
18th June 2007, 20:01
If you're encoding live DON'T use --no-fast-pskip, it slows things down a good bit for very little quality gain.

If your CPU can handle it use --subme 6 and --trellis 2.

Hellworm
18th June 2007, 20:17
You can use everything that is fast enough with your cpu and with a resolution of 320x240 thats propably pretty much (I would enable bframes, else --no-fast-pskip doesnt't make sense anyway) You can use vlc to do transcoding or you can for example transcode with ffmpeg to a file and stream the file. I remember having some problems with vlc's internal transcoder, but try it yourself.

btw did you mean 'from a single source' or 'to a single destination'?

webwonk
18th June 2007, 21:12
Thanks for the input fellas. The input is from an Osprey-230 (audio & video) across the bus - I've done this with windows media encoder/windows media services a lot - just never with h.264 before. the other difference will be that this is a Debian Etch linux box.

What I meant about single-source to single-destination is that there will be only one client attaching to this stream.

Any more experienced users willing to chime in? Most appreciated.

pandy
21st June 2007, 14:39
Additional advice - if You can, use a 640x480 downscaled to the 320x240 not directly 320x240 (lower quantization noises)