Easy G.729A
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Easy G.729A
Technical Document
Version 2.0－ Revision 2006-11-11
@Copyright 2004-2006 Imtelephone.com
No part of this manual may be reproduced in any form, written or otherwise, without the
express written permission of Imtelephone.com.
Easy G.729A
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Table of Contents
Introduction................................................................................................................. 3
PACKAGE CONTENTS........................................................................................... 3
CODEC COMPLEXITY............................................................................................ 3
ABOUT THE ENCODER/DECODER SAMPLE PROGRAMS............................. 4
EasyG729A API FUNCTIONS.................................................................................... 4
FAQS .......................................................................................................................... 6
Easy G.729A
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Introduction
EasyG729A is an implementation of ITU G.729A. EasyG729A support multiple
channels concurrent. There is no limit in concurrent channels and it can up to thousands
channels.
EasyG729A is an 8kbps
coder that encodes/decodes speech signal. The coder operates on
speech frames of 10 ms, corresponding to 80 samples at a sampling rate of 8000
samples/sec. In addition to the 10 ms speech frame duration, there is also a look-ahead delay of
5 ms, resulting in a total initial algorithmic delay of 15ms.
EasyG729A codec specifications
Bit rate (kbps)
8
Speech sampling rate(Hz)
8000
Frame duration (ms)
10
Look-ahead delay (ms)
5ms
Samples in one Frame 80
Frame size before encode(bytes) 160
Frame size after encode(bytes) 10
EasyG729A has a binary release version on Windows and Linux. The source code of
EasyG729A is written by C/C++, so you can easily port it to UNIX, PPC,DSP, Vxworks
or other operation system that support C/C++.
PACKAGE CONTENTS
EasyG729A.pdf This document
EasyG729A.lib
Win32 statically linkable library of G729A for Pentium and
compatible processors.
libG729a.a
Linux statically linkable library of G729A for Pentium and
compatible processors.
EasyG729A.h
API prototypes and constants declarations required by the
sample programs.
test_encode directory
Microsoft VC6.0 sample application and Linux GCC sample
application. Demonstrating encoder API calls to the codec
for encoding a speech file.
test_decode directory
Microsoft VC6.0 sample application and Linux GCC sample
application. Demonstrating decoder API calls to the codec
for decoding a speech file.
The encoder requires raw 16-bit mono PCM speech data sampled at 8000 Hz as input, i.e.,
without any header information. For every speech frame, consisting of 80*16 bit (160 bytes)
samples
CODEC COMPLEXITY
The codec complexity is represented as percentage of CPU usage, and is as follows when tested
on an Intel 800 MHz Celeron-MMX:
