embARC Audio Codecs Library for ARC Processors

The embARC Audio Codecs Library is a collection of voice audio codecs implemented in software for ARC EMxD and HSxD processors. An audio codec is a hardware device or computer program capable of encoding or decoding a digital audio signal including music and human speech. In software terms, an audio codec is a computer program implementing an algorithm that compresses and decompresses digital audio data.  The embARC Audio Codecs are a set of software libraries implementing legacy and commonly used codecs standardized by ETSI/3GPP and ITU-T.

Codecs Included in the embARC Audio Codecs Library

ETSI/3GPP Codecs

Codecs of this group are designed to transmit speech over a cellular network. GSM Full Rate (GSM-FR) was the first digital speech coding standard used in early deployments of GSM digital mobile phone systems. The GSM-FR bitrate is 13 kbps and has very moderate MIPS/memory requirements.

ITU-T Codecs

These codecs are implementations of G series of ITU-T standards. They are designed for voice transmission over Plain Switched Telephone Networks, Voice over IP, and mobile networks.

Bluetooth CVSD

Continuously Variable Slope Delta Modulation (BT-CVSD) is a mandatory codec for Bluetooth to transmit speech at 8 kHz sampling rate at 64 kbps.


LDAC is an audio coding technology developed by Sony, which allows streaming audio over Bluetooth connections up to 990 kbps at 24 bit/96 kHz (also called high-resolution audio). It is used by various Sony products.