Image manipulation. FFT, 2D Folding

[Brian Schröder]

Hello Group,

I want to do some image analysis and therefore I need to do a 2D FFT and inverse of images and fold some kernels about the image. Is there anything already available for this, or should I use narray, or is it generally a bad idea to do this in ruby?

Anybody has some experience with thoses things?

Regards,

Brian

 

[David G. Andersen]

Hello Group,

I want to do some image analysis and therefore I need to do a 2D
FFT and inverse of images and fold some kernels about the image.
Is there anything already available for this, or should I use narray,
or is it generally a bad idea to do this in ruby?

NArray, NImage, and FFTW would seem to be exactly what you're
asking for. (Note that if you install narray from the
freebsd port/package, it doesn't install nimage - you
have to go in and make it by hand for some reason).

-Dave

 

[Brian Schröder]

NArray, NImage, and FFTW would seem to be exactly what you're
asking for. (Note that if you install narray from the
freebsd port/package, it doesn't install nimage - you
have to go in and make it by hand for some reason).

-Dave

Thanks for the answer. I'm already playing with narray and it seems quite nice.

Regards,

Brian

 

[DaZoner]

Where is NImage documented? I can't find it in RAA or at NArray's homepage.

 

[Cameron McBride]

Greetings,

Where is NImage documented? I can't find it in RAA or at NArray's homepage.

it's a small addition to NArray.

% tar zxf narray-0.5.7p4.tar.gz
% less narray-0.5.7p4/nimage/README.en

Cameron

 

[Brian Schröder]

Where is NImage documented? I can't find it in RAA or at NArray's homepage.

Documentation for NArray and related things is really thin. It works great, but it seems to be under development and not yet fixed.

Also the NArray interface is not perfect. (E.g. It does not include Enumerable and each yields a nil as last value.)

Regards,

Brian

 

[David G. Andersen]

Documentation for NArray and related things is really thin. It works great, but it seems to be under development and not yet fixed.

Also the NArray interface is not perfect. (E.g. It does not include Enumerable and each yields a nil as last value.)

For what it's worth, I've found the author to be very responsive to
questions - I've submitted one bug and asked one very dumb question,
and he addressed both of them very quickly. Great package.

It could use some fleshing out. It'd be nice to be able to append
an element to the end of an array without having to explicitly resize
it (anyone figured out how to do that?), for instance.

-Dave