speech codec

Pepijn van den Berkhof pepijn.vandenberkhof at gmail.com
Tue Jul 26 18:26:27 UTC 2011


Thank you Harald for the response.

It seems to be working now although the only sounds we hear are "digital sounding" clicks and pops.

Thanks again.

- Pepijn
 
Op 25 jul 2011, om 09:39 heeft Harald Welte het volgende geschreven:

> On Sun, Jul 24, 2011 at 01:02:40PM +0100, Graham Palmer wrote:
> 
>> I too was wondering how the u-plane data was passed to the codec.
>> 300-395-2 states that acelp-codec requires 2 * (137+1) 16bit samples per frame
>> and not 216 + 216 bits indicated in the tch reordering file comments.
> 
> This is the input to the codec, i.e the PCM audio data.
> 
> the 216 + 216 bits are the encoded data, i.e. the codec output (which is
> the decoder input).
> 
> The re-ordering code in osmo-tetra is untested.  You can feed the raw
> burst bits into the ETSI reference codec, as it includes the error
> correction / viterbi decoder.
> 
> -- 
> - Harald Welte <laforge at gnumonks.org>           http://laforge.gnumonks.org/
> ============================================================================
> "Privacy in residential applications is a desirable marketing option."
>                                                  (ETSI EN 300 175-7 Ch. A6)
> 





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