[Linphone-developers] Is there any references papers on quality indicato
From:
Fu Jiantao
Subject:
[Linphone-developers] Is there any references papers on quality indicator
Date:
Fri, 23 Sep 2011 16:53:36 +0800
Hi all,
I'm using mediastreamer now, it's easy to use, even compiling it was painful in windows. When testing with mediastreamer.exe, I've seen it will print audio quality when processing rtcp, I've seen there's a file named qualityindicator which does the work, but I'm wondering where the formulas comes from.
static float loss_rating(float loss){ /* the exp function allows to have a rating that decrease rapidly at the begining.
Indeed even with 10% loss, the quality is significantly affected. It is not good at all. With this formula: 5% losses gives a rating of 4/5 20% losses gives a rating of 2.2/5 80% losses gives a rating of 0.2
*/ return expf(-loss*4.0); }