Re: re. sluggish CUSeeMe with 0.80b1

Jan Engvald LDC (
Tue, 24 Jan 1995 17:50:36 -0500

>I recently upgraded from a Macintosh Centris 650, System 7.1 (CUSeeMe ran
>great with version 68k0.70b13!).
>Got a PowerMac 8100/80AV, System 7.1 (CUSeeMe version ppc.0.80b1), same
>thing... very very sluggish! Any thoughts??

Today I compared the maximum frame rate on two systems and two versions:

ver 0.70b15 ver 0.80b1
Quadra 840AV 23 22 (68k version)
PowerPC 8100/80AV -- 12 (PPC version)

The settings were the same (CAP rate was set to 150 kbps not to be
a limit). Unfortunately the PPC didn't have ver 0.70b15, and there
was no time to fetch it.

But as can be seen the slowiness is more likely to be due to the PPC
than to the new CU-SeeMe version. Why the PPC is so slow I can only
guess. The Quadra 840AV uses a special signal processor to digitize
the video, whereas the PPC uses the main processor. A general purpose
processor is usually not as good as a dedicated processor for a given
task. It could of course also be that the CU-SeeMe code is not yet
optimized as much for the PPC as it has been for the signal processor.

Jan Engvald, Lund University Computing Center
Address: Box 783 E-mail:
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