Hi David Aha, now it starts getting clear. I was thinking about using two different samplingrates but, since I had not read anything about that, I was completely confused. But now I hope to have the first solution during this weekend.
dc6ny, helmut, and I, are very eager, to see, wether the new mode can be used when SSB does not bring any understandable signal anymore. When this would be the case, the 700mode could bring a revolution like from AM to SSB. Alfred On 20.08.2015 22:05, David Rowe wrote: > Hi Wully, > > The input sample rate for the speech samples is 8000Hz, output sample > rate for modem (in 700(B) mode) is 7500Hz. > > So with the 80ms frames that 700 uses: > > input speech: 8000 samples/s * 0.08s = 640 samples > modem output: 7500 samples/s * 0.08s = 600 samples > > - David > > On 20/08/15 22:57, wully wrote: >> Hi >> >> I am implementing the 700 mode now. First, I want to transmit. >> But I have a problem: >> >> When i ask for the speech- and modemsamples by >> >> speechsamplecount = freedv_get_n_speech_samples(freedv); >> modemsamplecount = freedv_get_n_nom_modem_samples(freedv); >> >> >> I get 640 for the speech, which is ok for processing the data at 7500 Hz >> samplerate. >> (Starting from 48kS/s downsampling). >> >> But the modemsamplecount reads 600. >> >> So, this would mean, that in my flow of speech at 7500Hz I would not get >> the necessary amount of >> samples (the same). I don't understand this. When I get only 600 >> modemsamples, my flow >> comes into starvation. >> >> What do I miss here? >> 73, hb9epu, Alfred >> >> >> >> >> ------------------------------------------------------------------------------ >> _______________________________________________ >> Freetel-codec2 mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 >> > ------------------------------------------------------------------------------ > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 ------------------------------------------------------------------------------ _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
