[PD] obscuring voices while maintaining intelligibility

[Hans-Christoph Steiner]

On Sep 22, 2011, at 2:19 PM, Lorenzo Sutton wrote:

> On 09/22/2011 07:15 PM, Hans-Christoph Steiner wrote:
>>
>> On Sep 22, 2011, at 5:29 AM, Lorenzo Sutton wrote:
>>
>>> On 21/09/2011 22:44, Hans-Christoph Steiner wrote:
>>>>
>>>> I'm trying to come up with a simple voice scrambling technique that
>>>> leaves voices understandable, but makes them unrecognizable. A  
>>>> key part
>>>> of this is to make it very hard to reverse the scrambling to make  
>>>> the
>>>> voice more recognizable.
>>>
>>> Ineresting. Also these possible approaches come to mind:
>>>
>>> - Trivial, probably off-topic: use a TTS. Only thing that is
>>> recognisable is the software which produced it.
>>> - Use some sort of granulation with random pitch-shifting. Not sure
>>> how easily reversible this would be.
>>>
>>> A fun thing might be mix the two: that is start from a TTS and then
>>> feed it into the granular... Here a silly example made with Festival
>>> TTS and granulation in Granita (the first sentence is the 'original'
>>> produced by Fesival) with different settings and degrees of
>>> recognisability:
>>>
>>> http://lorenzosu.altervista.org/temp/dump/voice01.ogg
>>
>> That sound has a lot of nice examples, can you share the patch for  
>> that?
>
> I was using my own Granita [1] which also has a "play" gadget.
>
>> text-to-speech is interesting, but that requires speech-to-text,  
>> which
>> is error prone and not something you can easily run in realtime on a
>> phone while processing video. Granular can be heavy too,
>
> True, I hadn't thought you were on resources budget, but indeed you  
> had mentioned CPU usage, Granita for ex.. is quite hungry, although  
> you can lower it's demands (see README). I don't think it would run  
> on a phone.. never tried though.
>
> Lorenzo.
>
> [1] http://lorenzosu.altervista.org/pd/granita/\

Granita looks quite nice and polished.  You should add it to the  
puredata.info downloads as an app.  Here's how:

http://puredata.info/docs/sitedocs/AddingYourProjectToDownloads

.hc


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