= TETRA Speech Codec =

The TETRA speech codec is part of the family of ACELP codecs.

For more information, please check out the following specifications: * ETSI EN 300 395-1 (General description of speech functions) * ETSI EN 300 395-2 (TETRA Codec) * ETSI EN 300 395-3 (Specific operating features) * ETSI EN 300 395-4 (Codec conformance testing)

ETSI has published a reference implementation of the codec implemented in C.

It is freely available together with ETSI EN 300 395-2.

In order to obtain it, follow the following procedure: * go to http://pda.etsi.org/ * enter "en 300 395-2" as search term * execute the search, there should only be one result in the list * click on the 'Download' link (top right part of the result table) * enter your e-mail address in the 'users without an ETSI account' field * click submit * click on the folder-like symbol on the bottom left side of the result table (see below) * you should now have a file called ''en_30039502v010301p0.zip''

Image(etsi_codec_download.png, 75%)