From duncan@rice.research.bell-labs.com  Mon Aug  2 18:43:13 1999
From: duncan@rice.research.bell-labs.com (Duncan Temple Lang)
Date: Mon, 2 Aug 1999 13:43:13 -0400
Subject: Advice interfacing to an imaging library
Message-ID: <199908021744.TAA02445@stat.math.ethz.ch>


> >>>>> "Richard" == Richard Beare <Richard.Beare@cmis.csiro.au> writes:
> 
>     Richard> 2) garbage collection. It is now easy to lose track of
>     Richard> memory, and this is likely to be significant because
>     Richard> images are usually quite big. There is a delete function
>     Richard> in the library, so it is possible to dispose of images
>     Richard> manually, but an automated method would be nice. One
>     Richard> option is to keep a global list of all pointers returned
>     Richard> from C function calls, generate a list of all image class
>     Richard> objects visible in R and compare the two. Any pointers
>     Richard> not on the image class list can be disposed. Does anyone
>     Richard> have any other ideas?
> 
> I'd look to embed a JVM into R and use all the power of Java for image
> processing and garbage collection. I've done it with xlispstat but not
> with R.
> ________________________________________________________________
> B. Narasimhan                            naras@stat.stanford.edu


My guess is that that would involve rewriting the existing library
written in C. Similarly, embedding the JVM still requires some
communication with the Java classes, etc. and conversion between the
R and Java data structures. This is where the meat of the interface lies.

However, on a more positive note, the embedding of the JVM into R and
S4/Splus5, John Chambers and I have been playing with, is getting very
close to being finished. I have been putting some of the final details
to it over the weekend. So the dynamic communication with Java
(i.e. dynamic method lookup and invocation) would not be that hard.

D.


-- 
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Advice interfacing to an imaging library
Duncan Temple Lang