Monday, September 16, 2019

AMBE and Codec2

About 10 years ago, when D-Star was really the only Digital Voice radio in ham radio, there was a bunch of fuss over how AMBE was not open like the rest of the D-Star protocol.

This may have very well started the Codec 2 project.  Its still a noble effort.  The problem is the VHF/ UHF dilemma has grown with the introduction of the digital voice radios like DMR and Yeasu's Fusion.  By the time these other modes came around, than initial fuss had simmered.

There were hopes initially that Codec2 could be a drop in replacement for AMBE.  And presumably if this happened perhaps manufactures would include this in future radio?

So here we are, 2019.  Back in Oct 2017, the patents surrounding AMBE for D-Star expired.  There is a crude sounding open-source AMBE code in mbelib that has been around for a while.

It appears in late 2018, Antony, SV9OAN started creating a vocoder extension "pydv" that allows the use of the open source Codec 2 with D-STAR.

"Provides Python interfaces to manage DExtra and DPlus connections (protocols used by reflectors), convert from network data to D-STAR streams (header and frames) and vice versa, as well as encode and decode voice data using mbelib (decode only) and codec2, and transcode using an AMBEd server (the version included in my xlxd fork)"

Sadly without some sort of D-Star radio firmware hacking project like Travis, KK4VCZ did with the MD-380 for DMR, I see Antony's work being a vain effort unless there is something I am missing?