Thanks Andreas, Very cool that demo can run on the command line! Such a great way of prototyping. A lot of the work in FreeDV (e.g. sound cards to modems to codecs, sample rate changes, fifo buffering) is simply to reproduce what the Linux command line does for us.
Good point from others re bit errors and encryption. However I imagine there are cipher systems that can work over HF, after all encrypted speech is a major application for HF DV. Once you get a few dB over the min SNR the bit error rate drops to zero with FEC. There is another application for SmartMic - secure telephony over the GSM voice channel. The idea is we develop a modem that can pass 1200 bit/s or so through the GSM _voice_ codec. This channel is pervasive around the world, reliable, and low latency (unlike mobile data). Cheers, David On Thu, 2014-05-29 at 14:37 +0200, Andreas Weller wrote: > > > On 21.05.2014 14:01, David Rowe wrote: > > I just posted an introduction to SmartMic - an embedded version of > > FreeDV that doesn't need a PC: > > Hi. > Great idea. What about adding an optional encryption layer - for non > Amateur Radio usage? This will make it an alternative for radio systems > used by many NGO relief orgs (UNHCR, UNICEF, Omar, Red cross). AFAIK > they are currently bound to Codan radios... > > Very simple example: > ./c2enc 1400 hts1a.raw - |openssl enc -rc4 -k Test|openssl enc -rc4 -d > -k Test| ./c2dec 1400 - - |play -t raw -r 8000 -s -2 - > > > Regards, > Andreas > > > > ------------------------------------------------------------------------------ > Time is money. Stop wasting it! Get your web API in 5 minutes. > www.restlet.com/download > http://p.sf.net/sfu/restlet > _______________________________________________ > Freetel-codec2 mailing list > Freetel-codec2@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 ------------------------------------------------------------------------------ Time is money. Stop wasting it! Get your web API in 5 minutes. www.restlet.com/download http://p.sf.net/sfu/restlet _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2
