I think I'll go ahead and implement the DCT definition directly ...I'm still
too new to Perl to make bindings with C code.
Thank you much for your help :)
________________________________
De: chm <[email protected]>
Para: cacarotov <[email protected]>
CC: [email protected]
Enviado: Domingo, 20 de noviembre, 2011 17:03:06
Asunto: Re: [Perldl] Discrete Cosine Transform
An upgrade of PDL::FFTW to FFTW3 has been
long desired. The current bindings are to
the FFTW version 2 of the library. One
approach would be to implement the DCT from
its definition(s), see
http://en.wikipedia.org/wiki/Discrete_cosine_transform
That won't be as fast but it should be
simple to implement. A faster implementation
would be to use the equivalence between the
DCT and DFT (see the section on DCT-II in the
above reference). Otherwise, you could implement
some bindings to some C DCT library or even
do the PDL::FFTW3 port.
Cheers,
Chris
On 11/20/2011 2:59 PM, cacarotov wrote:
>>
>>
>> ----- Original Message -----
>> From: "cacarotov"
>>
>>> Is there a PDL implementation for the Discrete Cosine Transform (DCT) ?
>>
>> According to Wikipedia the fftw library ( http://www.fftw.org/ ) "can
>> compute fast DCTs (types I-IV) in one or more dimensions, of arbitrary
>> size".
>>
>> So, if you have that library, and your build of PDL includes PDL::FFTW, you
>> might be able to do it that way - though there's no mention of discrete
>> cosine transforms in the PDL::FFTW documentation.
>> (Be aware that PDL::FFTW won't work with version 3 of the fftw library - the
>> latest version it works with is 2.1.5.)
>>
>> Cheers,
>> Rob
>>
>
> Just checked on the fftw documentation, and it looks that the DCT feature
> wasn't
> included until version 3 :(
>
> Do you have another suggestion ?
>
> Thanks for your reply.
>
> Sisyphus<sisyphus1<at> optusnet.com.au> writes:
>
>
>
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