2009/3/27 Gang Liu <gangban.lau at gmail.com> > We used a CMedia USB device as audio input device when we did resample test > before. > > MP3 player ---- line connect -- > USB --- 44khz ---> pjmedia app(the same > code as I published at google code) > > ---> PCMU stream ---> remote > > All at local LAN. > We used wireshark to capture G.711 stream. > And then compare this file again the orignal file and the 8khz file > converted by audacity. > It seems some high frequency was cut by pjmedia resampling. the quality not > good as audacity resampling. If change to 8khz, don't do resample anymore, > audio signal showed by audacity was OK. Also we tried Realtek HD audio > input of dell desktop pc. > > As I understand it, G.711 is not really a lossless compression codec, so some signal will be lost. Also the above involves analog connectivity too. So it's not a fair comparison IMO. For apple to apple comparison of the resample, use wav to wav resampling using pjsua method like I posted previously. cheers Benny -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20090327/2f4f6b8b/attachment.html>
