a_law.h File Reference

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Functions
uint8_t	sofm_a_law_encode (int16_t sample)
	sofm_a_law_encode() - Encode sample with A-law coding
int16_t	sofm_a_law_decode (int8_t byte)
	sofm_a_law_decode() - Decode A-law encoded code word

Function Documentation

sofm_a_law_decode()

int16_t sofm_a_law_decode

(

int8_t

byte

)

sofm_a_law_decode() - Decode A-law encoded code word

Parameters

byte	Encoded code word

The A-law decoder expands a 8 bit code word into a 13 bit sample value. In the SOF the high 13 bits are aligned to the most significant bits to be compatible with normal s16 Q1.15 samples.

Returns

: Sample value in s16 format

sofm_a_law_encode()

uint8_t sofm_a_law_encode

(

int16_t

sample

)

sofm_a_law_encode() - Encode sample with A-law coding

Parameters

sample

A s16 sample value

The A-law codec is defined in ITU-T G.711 standard and has been used in telecommunications in e.g. Europe. The A-law coding compresses 13 bit samples to 8 bit data stream. In SOF the high 13 bits of s16 format are used for compatibility with normal audios.

Returns

: Compressed 8 bit code value