Computer Vision Library in D

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On Wednesday, 20 April 2016 at 04:31:33 UTC, Relja Ljubobratovic 
wrote:

>> I'm interested in contributing towards parts that involve 
>> machine learning/numerical optimisation. I have written some 
>> of my own CV/ML programs with D in the past, but none of them 
>> are particularly well engineered since they were all intended 
>> for just my own use.
>
> That's great, thanks Henry! As I've noted above, I think it 
> would be wise to keep modules like ML and optimization apart 
> from this library, and to integrate dcv with them through 
> ndslice. Maybe it's more likely that you could contribute to 
> DlangScience's SVM libray with those parts? But any of your 
> previous CV experience is more than welcome for DCV - I'll 
> contact you on the github so we could discuss this further, 
> hope that's ok.

I have an implementation of BFGS in D (except [open]BLAS :). BFGS 
is an algorithm for unconstrained optimization of nonlinear 
smooth functions. It is NOT L-BFGS and requires O(n*n) memory for 
optimizing f: R^n -> R. The linesearch may be useful to implement 
other algorithms.

It works fine for me, but needs some refactoring. Given existing 
bindings for nlopt: would this be useful? If so, I start the 
refactoring.

For now, there are no benchmarks, but it is definitely 
faster/fewer iterations than optim(method="BFGS") in R and the 
algorithm should be better than the version in GSL (if n is not 
too large, GSL uses some kind of L-BFGS).