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:
_______________________________________________
Perldl mailing list
[email protected]
http://mailman.jach.hawaii.edu/mailman/listinfo/perldl
-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1411 / Virus Database: 2092/4028 - Release Date: 11/20/11
_______________________________________________
Perldl mailing list
[email protected]
http://mailman.jach.hawaii.edu/mailman/listinfo/perldl
