[comp.graphics] compressing images

arr@mtunf.ATT.COM (Andrew Raffman) (04/10/89)

Does anyone have any thoughts on what is the most effective way to
transmit still image video/pictures across a network, i.e. what is
the most effective method of compression, etc. I have heard of DVI,
but my impression is that it's designed for full motion video and
requires extra hardware, which may (or may not?) be overkill for this
situation. I would be interested in hearing about any other compression
techniques, both hardware and software, and about what standards exist
in this field. If I get enough interesting responses, I'll summarize to
the net.

Andy Raffman
AT&T Bell Labs
mtunf!arr 

gerry@cs.keele.ac.uk (Gerry Pratt) (06/29/89)

We have a large amount of SPOT image data here filling up our
disc and I wonder if anyone can tell me how to compress it.

Unix's compress don't do much good - about 25%-30% saving.
About a year ago there was a program call "squeeze" sent
out for doing this which I deleted to make some space on
the disc -:)

Also what about a "Linear Quadtree" algorithm for doing it.
Is there one of those out there?

Needless to say the method must work as a filter to unpack so
that it can be embedded in the application programs.

thanks,
gerry pratt - workstation support - university of keele
email: gerry@uk.ac.keele.seq1 * tel: (0782) 621111 x3290