Re: flexfax: Incoming faxes trashed

["James R. Hay" <jrhay@HayA.QC.CA>]

On 30 Apr 2000, Dmitry Bely wrote:

> "James R. Hay" <jrhay@HayA.QC.CA> writes:
> 
> > We have hylafax 4.0pl2 compiled on a Red Hat 6.1 system where we also
> > compiled tiff version 3.4 (we also tried 3.5).
> 
> Don't ever try 3.5 -- it will not work!

It had some sort of install error when I tried it.  I then tried 3.4 and
it appeared to install without complaint.
 
> > When a fax is received all
> > goes well.  When I try to print it the log contains several lines like:
> > 
> > Bad code word at scanline 265 (x 247)
> > 
> > When the job goes to the printer I get garbage.  I've tried opening the
> > tif file with various different viewers all of which complain about the
> > file being corrupted or an error occurring. 
> 
> This is pretty normal. Fax protocol (without ECM) is unreliable, and broken 
> scan lines sometimes happen. Hylafax by default stores them to TIFF file
> "as is".

Well, broken scan lines have happened with every test fax we've tried on
this machine so its a problem I have to fix.
 
> > Any suggestions of where to look for this?
> 
> You have a number of options to change this behaviour:
> 
> 1. If you use Class2/2.0 modem, and it supports quality checking, try to
> enable "receive copy quality correction" in the modem (man config for
> Class2CQCmd parameter and your modem's manual). E.g. for Zyxel Elite Class
> 2.0 the appropriate command would be "AT+FCQ=2,2". Note that many modems
> incorrectly reports that they support copy quality checking, although in
> fact they do not!

I'll have a look.  We have a MultiTech MT5634ZPX in this machine.
 
> (or)
> 
> 2. Force Hylafax to check/correct copy quality itself. By default it does
> not enabled in Class2/2.0 (if your modem reports CQ capabilities) and can
> be achieved with
> 
> Class2CQQueryCmd: "!(0),(0)"
> 
> in your config.<modem device>
> This way Hylafax will reencode the received image, and your viewer will be
> quite happy (although visible transmission errors will not disappear).

Ok, I'll have a look at that also.
 
> (or)
> 
> 3. Write ECM implementation for Hylafax (what I think about from time to
> time) :-)))

I'll need 48 hours days first:-(
 
> Hope to hear from you soon,

Thanks very much for your help.  I'll let you know what happens.

TTFN,
Jim.

James R. Hay				jrhay@haya.qc.ca
James R. Hay and Associates
P.O. Box 46003				ax25: ve2ve@ve2tcp#mtl.pq.can.noam
Pointe Claire, QC			amprnet: ve2ve@ve2tcp.ampr.org
H9R 5R4