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[hts-users:03599] Re: HTS-demo pulsenoise


Hi,

Hmm... You're probably right.
I think HTS-2.2 normal demo excitation can be considered as a kind of
'mixed excitation.'

Regards,
Keiichiro Oura


2013/2/6 Csapo Tamas Gabor <csapot@xxxxxxxxxxx>:
> Dear Keiichiro,
>
> Thank you very much for your answer.
>
> In the MELP standard that you cited it is written that "The pulse and noise
> excitation signals are then filtered and summed to form the mixed
> excitation." It is clear now that the voiced excitation in HTS-2.2 is a mix
> of impulses and noise. Does this mean that the HTS-2.2 normal demo system
> should be denoted / referred as 'mixed excitation' and not as 'pulse-noise
> excitation'?
>
> Best,
> Tamas
>
>
> 2013.02.06. 4:09 keltezéssel, Keiichiro Oura írta:
>
>> Hi,
>>
>> To reduce buzzy sound, low/high pass filter are used for excitation in
>> HTS-2.2 normal demo scripts.
>> You can check the effect by removing following line.
>>
>> $line .= "$DFS -b $lfil | $VOPR -a $gendir/$base.unv | ";
>>
>> The filter coefficients are described in
>>
>> Analog-to-Digital Conversion of Voice by 2,400 bit/second Mixed
>> Excitation Linear Prediction (MELP). United States Department of
>> Defense. Dec. 1999.
>>
>> Regards,
>> Keiichiro Oura
>>
>>
>> 2013/2/5 Csapo Tamas Gabor <csapot@xxxxxxxxxxx>:
>>>
>>> Hi All,
>>>
>>> I have seen that in the HTS-2.2 Normal demo (pulse-noise excitation) some
>>> noise is added above 6 kHz in the voiced regions:
>>>
>>> Training.pl, lines 1958 ... 1966
>>>   # synthesize waveform
>>>   $lfil = `$PERL $datdir/scripts/makefilter.pl $sr 0`;
>>>   $hfil = `$PERL $datdir/scripts/makefilter.pl $sr 1`;
>>>
>>>   $line = "$SOPR -m 0 $gendir/$base.pit | $EXCITE -p $fs | $DFS -b $hfil
>>> >
>>> $gendir/$base.unv";
>>>   shell($line);
>>>
>>>   $line = "$EXCITE -p $fs $gendir/$base.pit | ";
>>>   $line .= "$DFS -b $lfil | $VOPR -a $gendir/$base.unv | ";
>>> [...]
>>>
>>> Is there any reason for adding noise to higher frequencies of the
>>> pulse-noise excitation? This part of Training.pl wasn't there in the
>>> HTS-2.1.1 version, and I haven't found any changelog or paper that would
>>> explain why this has been introduced.
>>>
>>> Thanks and Best regards,
>>> Tamas
>>>
>>
>

Follow-Ups
[hts-users:03600] Re: HTS-demo pulsenoise, Csapo Tamas Gabor
References
[hts-users:03596] HTS-demo pulsenoise, Csapo Tamas Gabor
[hts-users:03597] Re: HTS-demo pulsenoise, Keiichiro Oura
[hts-users:03598] Re: HTS-demo pulsenoise, Csapo Tamas Gabor