I have constructed t38->g711 decoder using opal+spandsp_util.exe(t38->tiff).
The idea: ->t38(sip)->Opal(t38enpoint)->(t38->tiff)->Opal(FaxEndpoint)->audio-fax(G711-sip)
It works, but there is one small problem, if I use this construction with t38modem in NON-ECM mode.
T38modem(NON-ECM!!!)->t38(sip)->Opal(t38enpoint)->(t38->tiff)->Opal(FaxEndpoint)->audio-fax(G711-sip,NON-ECM)
It looks, as all is OK from t38modem side:good connect, good sending , and good end.
But there ane no fax picture at distination side. So, the distination is not recieving picture data(only picture data, all commands looks like well). If the fax picture is small, There is a chance that it will pass, but somehow with the very long delay. Or can get that will be a very small part (end of page).
At the same time in the ECM mode this construction works perfectly, almost simultaneously.
I would not write to you, if not for one circumstance.
If to replace T38modem to FaxOpal (t38), Zoiper, Hardware device with FXS and t38, with the same SIP-settings, then everything works perfectly (in ECM, and in NON ECM).
I tryed different versions of T38modem (with difference opal's), at different PC's, with different boundrates(14400-9600-...2400), I tryed t38 version 1 and 0 (old asn, with changening version in spandsp also),I tryed another programs instead of com0com, but rezult is very stable: with ECM-OK, no ECM- not OK. And only with t38modem.
May be it is possible to try to change something in t38modem-code. Some timeout,some delay, some buffer size. What difference in data sending between ECM and non ECM in this case? Something differ in t38modem from other t38-soft. What? I can not find.
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I have constructed t38->g711 decoder using opal+spandsp_util.exe(t38->tiff).
The idea: ->t38(sip)->Opal(t38enpoint)->(t38->tiff)->Opal(FaxEndpoint)->audio-fax(G711-sip)
It works, but there is one small problem, if I use this construction with t38modem in NON-ECM mode.
T38modem(NON-ECM!!!)->t38(sip)->Opal(t38enpoint)->(t38->tiff)->Opal(FaxEndpoint)->audio-fax(G711-sip,NON-ECM)
It looks, as all is OK from t38modem side:good connect, good sending , and good end.
But there ane no fax picture at distination side. So, the distination is not recieving picture data(only picture data, all commands looks like well). If the fax picture is small, There is a chance that it will pass, but somehow with the very long delay. Or can get that will be a very small part (end of page).
At the same time in the ECM mode this construction works perfectly, almost simultaneously.
I would not write to you, if not for one circumstance.
If to replace T38modem to FaxOpal (t38), Zoiper, Hardware device with FXS and t38, with the same SIP-settings, then everything works perfectly (in ECM, and in NON ECM).
I tryed different versions of T38modem (with difference opal's), at different PC's, with different boundrates(14400-9600-...2400), I tryed t38 version 1 and 0 (old asn, with changening version in spandsp also),I tryed another programs instead of com0com, but rezult is very stable: with ECM-OK, no ECM- not OK. And only with t38modem.
May be it is possible to try to change something in t38modem-code. Some timeout,some delay, some buffer size. What difference in data sending between ECM and non ECM in this case? Something differ in t38modem from other t38-soft. What? I can not find.
Sorry, I use t38->fax mode(gateway-mode) in spandsp_util.exe, not to->tiff, but ->to fax
Send me log files please.