Re: Compression Codecs

Netman (eabu927@ea.oac.uci.edu)
Thu, 27 Apr 1995 14:06:04 -0700 (PDT)


One thing though, what I've been trying to say is that MPEG-2
does the ENCODING/Decoding in REAL TIME...that fast...using ONE CHIP for
ENCODING and one CHIP for Decoding...RISC based chips..at about 50 MHz ..
In my opininion, this kinda of speed IS good for videoteleconferencing...

On 27 Apr 1995 Jay_Feldis@logitech.com wrote:
>
> [Text item: Compression Codecs]
> OriginalPath:
> I am also interested to know if CUseeMe will employ any kind of video
> compression. I would think this would help reduce bandwidth and/or
> increase frame rate.
>
> I think that MPEG is not really suitable for real-time live video
> however, becasue it works by looking at several frames at once and then
> generating vectors to represent the changes to the image over a period of
> time. As a result, you must store these frames long enough to do the
> compression which would cause a significant delay in the transmitted
> signal.
>
> The emerging video conferencing standard for ISDN telephone connections
> is ITU standard H.320. This is used by PictureTel and Vivo and many
> others. I don't know if this can be used via PPP connection however.
>
> There are a number of simpler compression algorithms that can give you
> 4:1 compression or so (executed in SW), this might not be too hard to
> implement.
>
> /Jay
>
> Did ya guys read "Multimedia Today".... the article "MPGEG-2: New
> World Standard for Digital Video"???????
> WOW up to 200:1 compression!!!!!!!!!!!!!!!!!!!!
> 30:1 at TV quality....of course CD sound quality....
> BACKWARD COMPATIBle with MPEG-!...
> HEY YOU GOOD PEople at cuseeme DEvelopment, What do you think? can you
> write something compatible with that codec?
> For more information here's a number 180-IBM-0181, ext. 1502 or send an
> email to JOHN G. Stamm at JSTAMM@vnet.ibm.com
>
> CHILLS GOING UP MY SPINE!!! Exciting Stuff!
> DisplaySubject: Compression Codecs