|
Hi All,
Please let me know the actual
difference between VAD option 1 and VAD
Option 2 in the GSM AMR codec. Under what
conditions is VAD option1 or VAD
option 2 is used ?
Thanks,
Harsha
|
|
|
AMR Codec VAD
Started by ●January 30, 2002
Reply by ●January 31, 20022002-01-31
|
Hello, Vad option 1 and 2 acts on different set of input test vectors. Test sequences DTX*.* are to be used with VAD option 1. Test sequencesDT2.*.* are to be used with VAD option 2. Refer to the GSM AMR document ETSI TS 126 074, where it discusses on AMR speech codec test sequences. From: "Harsha" <> To: <> Subject: [speechcoding] AMR Codec VAD Date: Wed, 30 Jan 2002 17:09:09 +0530 Hi All, Please let me know the actual difference between VAD option 1 and VAD Option 2 in the GSM AMR codec. Under what conditions is VAD option1 or VAD option 2 is used ? Thanks, Harsha LEARN TO FORGIVE BY PRACTICING FORGIVENESS, ARPAN |
Reply by ●February 1, 20022002-02-01
|
Dear Harsha, I just started working with the ETSI NB-AMR codec (floating point). I quickly gave a look in the document (ETSI EN 301 708 V7.1.0: Voice Activity Detector (VAD) for Adaptive Multi-Rate (AMR) speech traffic channels, GSM 06.94 version 7.1.0 Release 1998). You can download this document for free at www.etsi.org VAD1 and VAD2 are two different algorithms for Voice Activity Detection, which are explained in the document. The compiler option let you decide wich of the two algorithm you will use. By the way, I guess (because I could not find it in the documentation yet) that if you run the coder and encoder using -dtx in the calling line, you will efectively use the VAD at the coder and CNG (Comfort Noise Generation) at the decoder (I think DTX stands for discontinuous transmission). I hope this helps, Sara --- In speechcoding@y..., "Harsha" <harsha@m...> wrote: > Hi All, > > Please let me know the actual difference between VAD option 1 and VAD Option 2 in the GSM AMR codec. Under what > conditions is VAD option1 or VAD option 2 is used ? > > Thanks, > Harsha |
