http://qs1969.pair.com?node_id=1176303


in reply to Re^5: PDL: Looking for efficient way to extract sub-images, by finding bounding boxes of "objects" (7000x faster)
in thread PDL: Looking for efficient way to extract sub-images, by finding bounding boxes of "objects"

(*I have an idea about the cause of the slowness in 5.10; I'll need to think of a way to verify it.)
I came across this article a little while back. It might help explain the speed difference. I certain have seen a difference running a Perl application between 5.1x and 5.22.

How We Spent Two Days Making Perl Faster

Hope you find it interesting!