Re: [PLUG] Faxing Technology...

["William H. Magill" <magill@isc.upenn.edu>]

>       I was intresting in getting some more information about the Technology 
>   that goes into faxing.  More along the lines of is there a software package 
>   that would allow us to recive a incoming fax in a Computer.. be it windows or 
>   linux... and then send that fax to a printer.  We are tired of poor quality 
>   print that our fax machine gives out and that it ties up the line as well.  
>   Anyone know of such a peice of softwear?
>

There are a bunch of such products out there, basically divided into two
camps....

First off... a fax is an image. Second, it is NOT digital, it is analog.
There are also 2 major speeds/standards of FAX - Group 2 (old) and Group 3, 
contemporary.

That said, the two camps are -- receive the fax and store it as an image;
receive the fax and attempt to do OCR on the document.

The bulk of the "cheap" ($$-$$$) products receive the fax via your fax
modem, (which handles all of the fax-machine to fax-machine protocol
dialog), and store that received image as (all pages received) in one tif
or gif file, (a fax is a continuous transmission, which has no knowledge of
form-feed.) Newer software gives you more image storage formats. You then
view the fax via whatever software viewer matches the image type. Since
it's a "standard" (and I use the word loosely) image file, it can be
emailed, printed, or otherwise processed like any other file... except you
can't edit the text with an ASCII text editor, but you can do so (sort of)
with PhotoShop, or other image editing program. This style program
eliminates the fact that most "old" fax printers are lousy printers.
Usually being thermal printers, and all that implies for lousy image
quality. However, the problem of the scanner still exists.  If the
originating fax is a poor quality image, you can't improve upon it. 

So the second thing these cheap programs do is to "rasterize" your outgoing
fax for you. If you are sending an ASCII text file, that file is first
rasterized (converted to an image) and then shipped off to the modem for
transmission. Depending upon the quality of the program, this eliminates
the general problem of lousy fax quality on transmission.

The second group of products are usually quite expensive ($$$$), and even
their success is limited. Basically the idea that one can take an incoming
fax and convert it to a true digital source file (that is therefore
search-able) is still the holy grail of "Document Imaging Solutions."

If you have very specific criteria, like order forms or similar things, you
can actually set-up one of these systems to work reliably. However, you do
have to get the sender on-board to use the correct format for the OCR
scanner to recognize... etc.

Your reference to "ties up the line as well," kind of implies that you want
to do "fax over IP." Such things exist, but keep in mind, that any fax sent
over IP cannot be sent to a telephone connected fax! (Yes, there are
gateways, but that is the whole point, the IP network and the telephone
network are two different technologies which need a gateway between them,
so it isn't really worth the effort in the first place.

Any incoming fax is going to tie up the fax line for as long as it takes to
receive the fax. Today's machines all receive the complete fax first, hang
up the phone, and then print it. If it is taking a long time to receive a
FAX, and the print quality is poor, the implication is that you have an OLD
fax machine (a group 2 machine is S L O W compared to a group 3
machine!!!)! Just replace it.

And while incoming faxes can be received by computer, for $200 you can get a
brand new fax machine that will free up your computer for more useful
things. Unless you have an office where people are too lazy to go pick up
faxes from a central machine, it probably isn't worth the effort to use a
computer. And if you office is large enough to require distribution on
multiple floors, you probably have more than enough money to spend on 2 or
3 fax machines.

Just because you CAN do something with a general-purpose computer, does not
mean it makes practical, economic or operational sense to do so. The idea
that "special purpose devices" (even single purpose devices) can usually do
something much more efficiently, and normally much-much cheaper than a
general purpose device seems to get lost far too often. [And if you doubt
the cheaper argument, just try instructing your secretary on the intricacies
of keeping your Linux based fax server working, when all he needs to do
with the one from Xerox is to read the manual, that doesn't even exist for
the PC based one.]

-- 
                        www.tru64unix.compaq.com
                              www.tru64.org
                             comp.unix.tru64
                        
T.T.F.N.
William H. Magill                          Senior Systems Administrator
Information Services and Computing (ISC)   University of Pennsylvania
Internet: magill@isc.upenn.edu             magill@acm.org
http://www.isc-net.upenn.edu/~magill/

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