From: "Yvan Gagnon" <[EMAIL PROTECTED]>
Subject: Optimizing video quality with unique RealProducer settings

I was wondering if anyone here might be willing to share their
recommendations on what the ideal settings are for the encoding of different
bitrate realvideos.  I've done quite a bit of research and experimenting,
and I'm somewhat curious about certain things.

Typically, I encode my realvideo files for 4 different bitrates: 28k, 56k,
dual isdn, & DSL/Cable Modem.  While analyzing the statistics of the some of
the videos created by encoding.com  (who I've found get some pretty
outstanding results) I noticed that they generally use the following
settings:

28k - video : 160x120 - 6 fps | audio 6.5 kbps
56k - video : 176x132 - 6 fps | audio 8.5 kbps
Dual ISDN - video : 240x180 - 12 fps | audio 8.5 kbps
DSL/Cable Modem - video : 320x240 - 15 fps | audio 16 kbps


Question #1 :

If a Dual ISDN line can, in theory, handle something like 112 or 128 kbps,
.. why use a bitrate of only 80 kbps?  I'm noticing that this is also the
default setting assigned in RealProducer, and I'm just wondering if this
bitrate, -- and if all of these specific bitrates, -- were chosen for a
specific reason, .. like to allow for overhead (web surfing, email, etc,
... ) or if there's a performance consideration of some sort.  Why not
encode at 100kbps??  Or higher even?  I mean, . isn't an ISDN line
dedicated?


Question #2 :

Obviously, the above settings can't always apply.  For example, I had to
encode a clip this afternoon that had lots of fast motion in it, and I
couldn't help but notice that it looked like total shit at the lower
bitrates (28k and 56k) .  In these cases, meaning where there is lots of
motion in the video to be encoded,  what changes can I make to my settngs to
optimize clarity and at least get some half-decent looking results ??    The
only thing that I've noticed makes a difference is when I change the "Video
Quality" setting to "Sharpest Image Video", .. though the change is barely
even noticeable.


Question #3 :

What are the actual differences between "Normal Motion Video", "Sharpest
Image Video" and "Smoothest Motion Video" and when is it best to use each ??


Question #4 :

I don't know if I'm just having some kind of technical problem or if there's
a bug in the new realplayer, .. but when I encode a video at 15 fps, and
then monitor the statistics while playing the resulting realvideo file
locally using realplayer, for some reason, the frame rate that it plays back
with is nowhere near what I encoded it at.  For example, If  I've endcoded a
realvideo file at 15fps, .. why is realplayer telling me that it's playing
back at only 6-7 fps --- locally ??  This is a PIII 500 w/ 256 mb ram we're
talking about here.  Might this have anything to do with the fact that the
AVIs I'm encoding were originally captured at 15fps?  Or should this not
make any difference?


Any tips or advice would be much appreciated.

Thanks guys,
-- [EMAIL PROTECTED]



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