Codec question


although g729 uses a fraction of the bandwith of ulaw, i understood the sound quality should be better.

in reality i found it to be worse. is this to be expected?




long version- ulaw is the best quality codec you will get. Ulaw/alaw are also the only ones that will correctly represent fax or modem traffic as well as DTMF tones. g.729 is heavily compressed, mangles fax, modem and DTMF. Its primary use is to save bandwidth at the expense of CPU, as it offers pretty good quality, higher CPU usage and veyr low BW.

I agree with just about everything you said except the part about G-729 not handling DTMF that well, it handles DTMF pretty well actually but not faxing which i have discovered which for that we use uLaw to look after.

My preferrence in any case is to try and use uLaw where ever possible, however carriers these days want to push it down as low as possible even G.723 which i find to poses worse quality then G-729 (My opinion that is).

Just my 2/cents worth :wink: