Polycom 3725-70003-009F Manuale Utente

Customizing & Branding Your ReadiVoice System

Proprietary & Confidential 

175

  

Details About the WAVE File Format 

A WAVE file stores digital (sampled) audio data in Microsoft’s Resource 

Interchange File Format (RIFF). RIFF is a variant of Electronic Arts’ Interchange 
File Format (IFF). Unlike IFF, the Intel-oriented RIFF uses Little Endian byte 

order. For more information about RIFF, visit the Microsoft Developer 
Network (

RIFF files consist of logical units of data called chunks. The first chunk in a RIFF 
file is the RIFF chunk. All other chunks in the file are subchunks of the RIFF 
chunk. 
At a minimum, all WAVE files contain: 
• The top-level RIFF chunk, which consists of three parts: 

— The chunk identifier, which is the four-character code RIFF. 
— The size of the data member chunks, a DWORD (four-byte integer). The 

size is everything after the first eight bytes (the chunk identifier and 
the size DWORD itself). 

— The data member, which begins with a DWORD that specifies the form 

type of the chunk (in this case WAVE). All other chunks in the file are 

considered part of the data member of the RIFF chunk. 

• A Format subchunk that describes the data (sample rate, bit resolution, 

type of compression, and so forth). 

• A Data subchunk that contains the actual sampled audio data. 
But, RIFF (like IFF) is extensible. WAVE files can contain, and developers can 
define, additional types of chunks to provide additional data and 
functionality. 
Polycom added two new chunks to the WAVE file format to create its indexed 
WAVE files. They’re described in the “

section.