Sending fax through g729

the only thing i’ve been able to do is through g711 choosing t.38 on the ata (wordaccxx), and choosing ulaw on sip.conf. What kind of configuration must i make to send through g729? thanks

G729 and fax do not ever, ever go together ! … dCODECsnot

From the wiki

Using Compressed CODECs (not)
Can I fax over a call with GSM codec compression? What about G.729? Other complex codecs?

See Steve Underwoods excellent document about how fax over IP works. Quoting from the page:
“The commonest problem with sending a FAX over VoIP networks is the easiest to deal with. A low bit rate voice codec is unable to carry a fast modem signal without severe distortion. Would you really expect an 8kbps G.729 codec to convey a 9.6kbps FAX modem signal correctly?”

Therefore, the GSM codec is never going to be appropriate for sending faxes. Besides, if you need low bitrates for your IP connection, you’re likely to experience delays in the fax negotiation ? which will probably result in a failed fax attempt. If you want to be able to send faxes in this way, then negotiate the fax at one end, and email the resulting TIFF graphics file to the other end.

Hello all, xtremeclones what config do you have for your working fax setup with g711?

Hi, preety much what i put above, did you mean anything in specific?

Yes, I mean for the fax setup what did you put where in which config files?