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
>
>
>
>
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