|Re: [eigen] Adapting code from OpenCV (a seemingly much faster SVD)|
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] Adapting code from OpenCV (a seemingly much faster SVD)
- From: Patrick Mihelich <patrick.mihelich@xxxxxxxxx>
- Date: Sat, 18 Apr 2009 21:20:25 -0700
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OpenCV recently scrapped its own linear algebra code in favor of LAPACK. It didn't make much sense for OpenCV to have its own versions. I doubt the SVD was doing anything terribly fancy; it probably got its speed edge from hand-optimized loop unrolling, etc.
The internal implementations of OpenCV functions are thoroughly evil due to the lack of support for generic programming in C. Porting code from it I think would not be easier than writing from scratch.
On Sat, Apr 18, 2009 at 8:02 AM, Hauke Heibel <hauke.heibel@xxxxxxxxxxxxxx>
Benoit, you are much closer to the core math than I am and I think that its not really a good idea port the OpenCV code - at least not for me. :)
OpenCV does not
- support fixed size specializations
- handle complex numbers
I will simply send you the code I have so you may take a look at it. As I said before, the original code is gone from OpenCV. At least I cannot find it in the SVN and the old CVS repository seems to be down.