User`s manual
Page 37
DVSI Confidential Proprietary
USB-3000™
User’s Manual
Version 1.6a
Section 3- Operation
Digital Voice Systems, Inc.
The Speech Compression Specialists
<file name>.pcma -- (a-law format audio file 8 bit audio file sampled at 8kHz.)
file name>.pcmu -- (µ-law format audio file 8 bit audio file sampled at 8kHz.) <
Encoded Files
Encoded Files are files that have been encoded using the USB-3000™. They are located in each of
ated with a .bit extension in the file
ame as show
file name>.bitu -- (encoded data file from a µ-law audio format file.)
e Table 16 Standard Rate Table for AMBE-3000™ Vocoder Chip (by
index number).
in directory r39 is a compressed data file encoded at rate index 39, which is a data rate of
600bps.
r<rate_index> subdirectories of the tv directory. Encoded files are indic
n belown
<file name>.bit -- (encoded data file from a pcm audio format file.)
<file name>.bita -- (encoded data file from an a-law audio format file.)
<
The encoder data rate is indicated by the rate index v
alue that is part of the directory name. Rate index values
are referenced in th
For example,
the file clean.bit
3
where as,
the file clean.bit in directory r42 is a compressed data file encoded at rate index 42, which is a data rate of
4800bps.
Processed files (Encoded / Decoded)
Processed files are files that have been Encoded / Decoded through the USB-3000™. They are located in each
with a .pcm extension in
e file name n below
me>.pcmu -- (encoded/decoded data file from a µ-law audio format file.)
er data rate is indicated by the rate index value that is part of the directory name. Rate
m in directory r39 is a pcm file that was encoded/decoded at rate index 39, which is a data
te of 3600bps.
here as,
oded/decoded at rate index 42, which is a data
act, yet includes all necessary code to communicate with the USB-3000™, provide interrupts
r ti es the channel packet protocol. The source code for the program is provided as an
of r<rate_index> subdirectories of the tv directory. Processed files are indicated
as showth
<file name>.pcm -- (encoded/decoded data file from a pcm audio format file.)
<file name>.pcma -- (encoded/decoded data file from an a-law audio format file.)
<file na
The encoder/decod
index values are referenced in the Table 16 Standard Rate Table for AMBE-3000™ Vocoder Chip (by index
number).
For example,
the file clean.pc
ra
w
the file clean.pcm in directory r42 is a pcm file that was enc
te of 4800bps. ra
3.4. USB3kcom.exe Program Description
The usb3kcom.exe program is written entirely in C and C++ to facilitate easy modification by customers. The
software is comp
fo ming and arrang
example to assist in the creation custom programs. This software demonstrates useful features of the AMBE-