About 5 or 6 years ago Stefan Bilbao gave me some Matlab code for a
platerev operation based on PDE finite difference formulation.

Have a few minutes spare yesterday I re-found the work I had already
done to implement in C, and last night and today I finished an opcode.
The sound transformation is subtle and in my simple example rather
beautiful;  on the other hand it is computationally expensive (about
four times longer than real time).  I have tentatively added it to git
but have not yet written a manual page.

Current version is stereo, but could be made mono to some advantage.
I think I can speed it up a little but I have already done a lot of
breathing.

Anyone interested?  Want to try it?  Or should I just shelve it?
==John ffitch

Definitely!

Why not make it polymorphic mono/stereo?

John Lato might have something to say about possible optimisations. He was working with some of Stefan's models and made some of the plate ones run in realtime by reworking some of the matrix operations. Not sure if he is still in this list.

Regards

Victor


On 13 Jun 2012, at 19:25, john ffitch wrote:

> About 5 or 6 years ago Stefan Bilbao gave me some Matlab code for a
> platerev operation based on PDE finite difference formulation.
> 
> Have a few minutes spare yesterday I re-found the work I had already
> done to implement in C, and last night and today I finished an opcode.
> The sound transformation is subtle and in my simple example rather
> beautiful;  on the other hand it is computationally expensive (about
> four times longer than real time).  I have tentatively added it to git
> but have not yet written a manual page.
> 
> Current version is stereo, but could be made mono to some advantage.
> I think I can speed it up a little but I have already done a lot of
> breathing.
> 
> Anyone interested?  Want to try it?  Or should I just shelve it?
> ==John ffitch
> 
> 
> Send bugs reports to the Sourceforge bug tracker
>            https://sourceforge.net/tracker/?group_id=81968&atid=564599
> Discussions of bugs and features can be posted here
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"
> 

Dr Victor Lazzarini
Senior Lecturer
Dept. of Music
NUI Maynooth Ireland
tel.: +353 1 708 3545
Victor dot Lazzarini AT nuim dot ie

Sure I am interested!
Can you show the csd?
In git, that means the opcode needs to be compiled first?

Richard

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View this message in context: http://csound.1045644.n5.nabble.com/Possible-new-opcode-tp5713761p5713763.html
Sent from the Csound - General mailing list archive at Nabble.com.

If it sounds good, it should be an opcode, that should be the rule.
Time is important but not that important.

Regards,
Mike

On Wed, Jun 13, 2012 at 2:40 PM, zappfinger  wrote:
> Sure I am interested!
> Can you show the csd?
> In git, that means the opcode needs to be compiled first?
>
> Richard
>
> --
> View this message in context: http://csound.1045644.n5.nabble.com/Possible-new-opcode-tp5713761p5713763.html
> Sent from the Csound - General mailing list archive at Nabble.com.
>
>
> Send bugs reports to the Sourceforge bug tracker
>            https://sourceforge.net/tracker/?group_id=81968&atid=564599
> Discussions of bugs and features can be posted here
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"
>



-- 
Michael Gogins
Irreducible Productions
http://www.michael-gogins.com
Michael dot Gogins at gmail dot com

> Sure I am interested!
> Can you show the csd?
> In git, that means the opcode needs to be compiled first?
>
> Richard
>

A Debian plugin will be available tomorrow

Working on example and documentation

>
> Why not make it polymorphic mono/stereo?
>

There are some real problems in making it polymorphic.  The problem really
lies in the excitation signal rather than the output.  As originally
written it inseerts n channels at different points and reads n outputs
also from arbitrary points.  To specify the in and out points requires 3
parameters each bper channel.   I suppose these data could be in a table
which would shorten the argument list, and also separate number if ins and
ous.  Does that sound (!) like a good idea?

> John Lato might have something to say about possible optimisations. He was
> working with some of Stefan's models and made some of the plate ones run
> in realtime by reworking some of the matrix operations. Not sure if he is
> still in this list.
>

A large part of the expense is the insertion and output, which has way too
many sin/cosine calculations.  These should be made incremental for each
k-cycle....  Will try rewrite soon.

==John ff

I have adjusted along the lines mentioned here -- seems to be working but
needs more testing anf needs revised manual page
==John

>>
>> Why not make it polymorphic mono/stereo?
>>
>
> There are some real problems in making it polymorphic.  The problem really
> lies in the excitation signal rather than the output.  As originally
> written it inseerts n channels at different points and reads n outputs
> also from arbitrary points.  To specify the in and out points requires 3
> parameters each bper channel.   I suppose these data could be in a table
> which would shorten the argument list, and also separate number if ins and
> ous.  Does that sound (!) like a good idea?
>
>> John Lato might have something to say about possible optimisations. He
>> was
>> working with some of Stefan's models and made some of the plate ones run
>> in realtime by reworking some of the matrix operations. Not sure if he
>> is
>> still in this list.
>>
>
> A large part of the expense is the insertion and output, which has way too
> many sin/cosine calculations.  These should be made incremental for each
> k-cycle....  Will try rewrite soon.
>
> ==John ff
>
>
>
>
> Send bugs reports to the Sourceforge bug tracker
>             https://sourceforge.net/tracker/?group_id=81968&atid=564599
> Discussions of bugs and features can be posted here
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
> csound"
>
>
>
>