Audio Format Specifications

The following are the specifications for the audio capture format.

Property	Detail	Expected by SP

Property	Detail	Expected by SP
'RIFF'	RIFF file identification	‘RIFF’
'WAVE'	File Type Header. For our purposes, it always equals “WAVE”.	‘WAVE’
fmt marker	format sub-chunk identification OR Format chunk marker.	'fmt'
fmt size	length of format data or Sub-Chunk size	16
Audio format	format specifier (Type of format (1 is PCM) - 2 byte integer)	1
channels	number of channels	1
sample rate	sample rate in kHz	16 / 44.1 / 48
bit depth	bit depth (Bits per sample)	16

Summary 16000 :

RIFF (little-endian) with 'fmt' marker and fmt-size = 16, WAVE audio,16 bit-Microsoft PCM, mono, 16000 Hz

Summary 44100 :

RIFF (little-endian) with 'fmt' marker and fmt-size = 16, WAVE audio,16 bit-Microsoft PCM, mono, 44100 Hz

Summary 48000 :

RIFF (little-endian) with 'fmt' marker and fmt-size = 16, WAVE audio,16 bit-Microsoft PCM, mono, 48000 Hz

Example log

fmt_size                = 16
header_size             = 550948
format                  = 1
channels                = 1
sample rate             = 44100
blocksize               = 2
byte per sec            = 88200
bit depth               = 16
header_data_size        = 550912
sample count            = 275456
actual extracted samples extracted = 275456