readme.txt

Purpose: Explanation file of objective measure implementation for
         NS algorithm characterisation
Source:  Nokia (utilises ITU-T P.56 software for sv56 Speech Voltmeter)


NOTE 1:  The source code files implementing the ITU-T P.56 software for
         sv56 Speech Voltmeter, and their inclusion in this distribution,
         are subject to the "ITU-T SOFTWARE TOOLS' GENERAL PUBLIC LICENSE". 
	 Thereby all source code included in this distribution of the 
	 objective measure implementation for NS algorithm characterisation 
	 and all derivations of said source code are subject to the 
	 "ITU-T SOFTWARE TOOLS' GENERAL PUBLIC LICENSE".
         This licence can be found in the included text file "gen-lic.txt"
         or in the ITU-T Recommendation G.191 on "SOFTWARE TOOLS FOR SPEECH
         AND AUDIO CODING STANDARDS".


Introduction
============

This file lists the content of an ensemble files comprising a C code
implementation of two objective speech quality measures designed
for the characterisation of noise suppression (NS) algorithm effect
on noisy speech. The C code package is a part of the ETSI Techical
Specification 06.77, or "Digital cellular telecommunications system
(Phase 2+); Minimum Performance Requirements for Noise Suppresser
Application to the AMR Speech Encoder".

The included objective measures are
- SNRI (Signal-to-Noise Ratio Improvement)
- NPLR (Noise Power Level Reduction)

A formulation of the objective measures, as well as the preferred
test conditions, are given in the said standard specification.


Files
=====

Source code
-----------
DescDb.c        description of noisy speech database
main.c          main program, statistical analysis and generation
                  of report
main.h          header file for main.c and process.c
process.c       computation of objective measures

SV-P56.C        ITU-T P.56 active speech level meter (see NOTE 1 above).
SV-P56.H        header file for SV-P56.C (see NOTE 1 above).
UGST-UTL.C      ITU-T speech toolkit library utilities (see NOTE 1 above).
UGST-UTL.H      header file for UGST-UTL.C (see NOTE 1 above).

C compiler configuration files
------------------------------

snrinplr.dsp    Microsoft Visual C++ 6.0 project file of target program
snrinplr.dsw    Microsoft Visual C++ 6.0 workspace file for target program

Executable files
----------------

snrinplr.exe    Microsoft Windows NT 4.0 DOS prompt executable of target

Informational files
-------------------

Results.txt     example dummy report file


Contacts
========

Erkki Paajanen
Nokia Research Center
erkki.paajanen@nokia.com

