SW300070-EVAL Microchip Technology, SW300070-EVAL Datasheet
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SW300070-EVAL
Manufacturer Part Number
SW300070-EVAL
Description
SOFTWARE LIBR ENC/DEC EVAL ONLY
Manufacturer
Microchip Technology
Type
Speech Encoding/Decoding Libraryr
Datasheet
1.SW300070-EVAL.pdf
(2 pages)
Specifications of SW300070-EVAL
Tool Function
Library
Tool Type
Library
Processor Series
dsPIC30F
Core Architecture
dsPIC
Lead Free Status / RoHS Status
Not applicable / Not applicable
For Use With/related Products
dsPIC30F
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
dsPIC30F Speech Encoding/Decoding Library
Summary
The dsPIC30F Speech Encoding/Decoding Library performs
toll-quality voice compression and voice decompression. The
library is based on a modified version of Speex source code
and features a 16:1 compression ratio. It samples speech
at 8 kHz and compresses it to a rate of 8 kbps. Storing
compressed speech for playback requires approximately
1 KByte of memory for each second of speech. The library is
especially suitable for the following voice-based applications:
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Description
The Speech Encoding/Decoding Library is a modified
version of the Speex speech coder made specifically for
the dsPIC30F family of Digital Signal Controllers (DSCs).
Encoding uses Code Excited Linear Prediction (CELP), which
is a popular coding technique. CELP provides a reasonable
trade-off between performance and computational complexity.
The library samples speech at 8 kHz and compresses it to
a rate of 8 kbps. The library is appropriate for half-duplex
systems, such as answering machines, intercoms and walkie-
talkies. With the decoder’s small footprint, the library is also
ideal for playback-only applications, such as building safety
systems and smart appliances.
Predominantly written in assembly language, the Speech
Encoding/Decoding Library optimizes computational
performance and minimizes RAM usage. A well-defined API
makes it easy to integrate with your application.
A flexible analog interface gives your design several
options to consider. The speech encoder samples speech
at 8 kHz using either an external codec or the on-chip
12-bit analog-to-digital converter. The speech decoder
plays decoded speech through an external codec or the
on-chip pulse-width-modulator (PWM).
A PC-based Speech Encoder Utility program (pictured above)
allows you to create your own encoded speech files for
playback. Encoded speech files are made from either a PC
microphone or existing WAV file. Once you create the encoded
speech files, they are added to your MPLAB® C30 project, just
like a regular source file, and built into your application.
The Speech Encoder Utility allows you to select four target
memory areas to store your speech file: program memory,
data EEPROM, RAM and external flash memory. External flash
memory allows you to store many minutes of speech
(1 minute of speech requires 60 KB) and it is supported
through a dsPIC30F general purpose I/O port.
Answering machines
Building and home safety systems
Intercoms
Smart appliances
Voice recorders
Walkie-talkies
Any application using message playback
M i c r o c h i p T e c h n o l o g y I n c o r p o r a t e d
Features
Key features of the Speech Encoding/Decoding Library include:
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Encoder Utility. It allows you to make encoded speech
files from your desktop using a PC microphone or WAV file
second of speech
Guide is provided to help the user understand and use
the library (DS70154)
Development Board (DM300014)
Fixed 8 kHz sample rate
Fixed 8 kbps output rate
PESQ-based Mean Opinion Score: 3.7 – 4.2 (out of 5.0)
Code Excited Linear Prediction (CELP)-based coding
Two analog input interfaces – codec or on-chip 12-bit ADC
Two analog output interfaces – codec or on-chip PWM
Optional Voice Activity Detection
Playback-only applications will benefit from the Speech
Storing compressed speech requires 1 KB of memory per
Off-chip support for playback of long speech samples
Royalty free (only one-time license fee)
Full compliance with Microchip MPLAB® C30 Language
Tools
dsPIC30F Speech Encoding/Decoding Library User’s
Designed to run on dsPICDEM™ 1.1 General Purpose
Related parts for SW300070-EVAL
SW300070-EVAL Summary of contents
Page 1
Speech Encoding/Decoding Library Summary The dsPIC30F Speech Encoding/Decoding Library performs toll-quality voice compression and voice decompression. The library is based on a modified version of Speex source code and features a 16:1 compression ratio. It samples speech at 8 ...
Page 2
... Half-duplex support is now possible and requires 6 RAM. Part Numbers and Ordering Information dsPIC30F Speech Encoding/Decoding Library Part Number SW300070-EVAL dsPIC30F Speech Encoder/Decoder Library Software License (Evaluation Only) SW300070-5K dsPIC30F Speech Encoder/Decoder Library Software License ( Units) SW300070-25K ...