Hi Alfred, I haven't actually measured the CPU load of 700 yet. Often it's just one small function that is taking all of the MIPs. The current CPU load of 700B will have no relationship to the CPU load when optimised.
Would some one on the list like to profile freedv_tx and freedv_rx and see where the MIPs are going? That would be very helpful. The SNR values should be roughly the SNR of the channel, so at the lower limit (when 700B is breaking down) about 0dB. In a fade it may drop to negative values. It reads correctly for me. The cohpsk_demod program can output SNR for you - maybe try running this program with a file of Fs=7500Hz, 16 bit samples from your off-air signal. You could also try running the FreeDV GUI program with off air samples or connected to another receiver. See what SNR values it presents. It may be some issue with the SNR routine that you have found, in that case we can track it down with some more tests. Cheers, David On 03/09/15 04:28, wully wrote: > Hi > > I am experimenting further with the 700B mode. It seems that this mode > uses quite a bit of cpu cycles during rx, substantially more than the > 1600 mode. I am using a relatively slow cpu, which runs my sdr code at > about 20-25% cpu in SSB, when I switch to 700B rx, the cpu increases to > about 45-50%. > > I assume, that the 700B makes extensive calculations? > > > Question about SNR-estimation: > > I just display the value codec2snr that I get from calling > > int codec2sync; > float codec2snr; > > freedv_get_modem_stats(freedvRx,&codec2sync,&codec2snr); > > What are the typical values that should appear? > > Thanks > Alfred, hb9epu > > > > ------------------------------------------------------------------------------ > Monitor Your Dynamic Infrastructure at Any Scale With Datadog! > Get real-time metrics from all of your servers, apps and tools > in one place. > SourceForge users - Click here to start your Free Trial of Datadog now! > http://pubads.g.doubleclick.net/gampad/clk?id=241902991&iu=/4140 > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > ------------------------------------------------------------------------------ Monitor Your Dynamic Infrastructure at Any Scale With Datadog! Get real-time metrics from all of your servers, apps and tools in one place. SourceForge users - Click here to start your Free Trial of Datadog now! http://pubads.g.doubleclick.net/gampad/clk?id=241902991&iu=/4140 _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
