dsPIC DSC Speex Speech Encoding/Decoding Library
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dsPIC DSC Speex Speech Encoding/Decoding Library 
Part Number: SW300070

Summary

The dsPIC® DSC Speex Speech Encoding/Decoding Library performs toll-quality voice compression and voice decompression. The library is a modified version of the Speex speech coder and is optimized specifically for the dsPIC DSC family of Digital Signal Controllers (DSCs). It uses Code Excited Linear Prediction (CELP), which is a popular coding technique. The library supports both Narrowband and Wideband modes. It samples speech at 8 kHz or 16 kHz and compresses it to a selectable bit rate. The compressed speech data now requires less memory for storage or less bandwidth for communication.

Applications:

Answering machines
Building and home security systems
Intercoms
Smart appliances
Voice recorders
Walkie-talkies
Toys & Robots
Any application using message playback

Features


The dsPIC DSC Speex Speech Encoding/Decoding Library has the following features:


Simple user interface – only one library file and one header file.
All functions called from a C application program
Full compliance with the Microchip C30 Compiler, Assembler and Linker
Highly optimized assembly code that uses DSP instructions and advanced addressing modes.
Compact and concise API for easier integration with application
Four modes:
8 kbps at 8 kHz sampling rate (Narrowband) – 16:1 compression ratio
11 kbps at 8 kHz sampling rate (Narrowband) – 11.63:1 compression ratio
9.8 kbps at 16 kHz sampling rate (Wideband) – 26.12:1 compression ratio
12.8 kbps at 16 kHz sampling rate (Wideband) – 20:1 compression ratio
Library contains a Speex version optimized for 8 kbps mode
Speex PC Encoding Utility for recording and encoding speech through a PC with output files generated for program memory, data EEPROM or RAM
Audio bandwidth: 0-8 kHz with sampling rate of up to 16 kHz
● Multiple encoders and/or decoders can be instantiated
● F
ull-duplex and half-duplex operations
● Encoder and decoder can share scratch memories for optimal RAM usage

Can be integrated with Microchip’s Noise Suppression, Acoustic Echo Cancellation and Line Echo Cancellation Libraries
Library delivered on CD which includes:
Sample demo applications with complete source code
User’s guide
HTML help files for PC Encoding Utility (PCEU)

Resource Requirements


Please refer to user’s guide for resource requirements



Other Related Resources:

16bit Speech & Audio Solutions
Web Seminar
Audio & Speech Solutions Design Center

 

This library is available for free download and there are no associated royalties for this library.

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