From: ara.t.howard@...
Date: 2005-12-29T11:11:51+09:00
Subject: Re: Real-time image processing in Ruby

On Thu, 29 Dec 2005, John Koschwanez wrote:

> I'm a Ruby newbie - "Programming Ruby" was great Xmas break reading!
> I write image analysis and processing code to analyze single cells under
> a microscope in real-time and to automate lab equipment.  I now write
> solely in C++ for PC, but I would love to use Ruby to quickly try new
> ideas without plowing through C++ code.  I have read through the forums
> and I see Ara Howard is using C extensions to process images - I'll try
> the same thing.  I have some questions for the group:
> - I capture images from a camera, process and analyze them, and display
> them at ~10 fps.  Ruby-v4l (capture) is for Linux only.  Tk is probably
> too slow, and someone recommended using OpenGL for display.  Has anyone
> had success with image capture or display using Ruby?  What worked?  Any
> advice?
> - Is anyone using pure Ruby to process images real-time?  RMagick is too
> limited for my applications.  I doubt Ruby would match the speed of C,
> but it might be fun to try.
> Thanks, John



i'm not doing anything near-realtime, but you may want to check this out:

   http://artengine.ca/gridflow/

my understanding is that it's used for realtime video processing, so images
might be possible too.

i must say, however, that it seems like doing what you are doing, especially
in linux only, might be possible with rmagick only - just dump the frames in
/dev/shm and go...

another option, quite suitable for prototyping only, is just using narray : i
use it together with a hack that allows the grids to be mmap'd quantities so
'image processing' is nothing but matrix ops... narray ships with a simple
method of displaying images under x.  at 10 fps this might just hack it.

regards.


-a
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