I think autopano-sift-c is maintainable, it doesn't have any awkward 
dependencies, and as far as I know still builds on all platforms despite 
abandonment. If you want to take it on then please dive-in.

I'll try and recall some history:

The C# implementation (which involved running two tools consecutively) was 
replaced by the C version that was contributed anonymously, this is the code 
that you can find on sourceforge.

Hugin has never shipped with an autopano-sift-c executable because of a SIFT 
algorithm patent (though Hugin has the capability to run autopano-sift-c for 
control-point finding if you have it).

Pablo wrote cpfind as a full replacement that doesn't infringe the SIFT patent, 
this *is* shipped with Hugin, and as far as I'm concerned cpfind is as capable 
and as fast at feature identification as autopano-sift-c. There hasn't been 
much interest in autopano-sift-c since.

I believe that the SIFT patent expired last year, so there is some value in 
looking at all this again - in particular because (as you have identified) 
there are some very mature GPU based SIFT implementations in libraries like 
opencl.

So, upgrading autopano-sift-c to use a modern SIFT implementation would be 
interesting, but there are two drawbacks: we don't actually know who wrote it, 
though they did attach a GPL licence, so it has an odd copyright status; it 
also reads a limited range of image file formats, whereas cpfind can read all 
the formats supported by Hugin.

Modifying cpfind in the Hugin project to use a modern SIFT library *could* 
produce a dramatic improvement in speed and quality (though nobody knows 
without trying), if so, and if it doesn't involve exotic library dependencies, 
it would be welcome as part of Hugin. This would be the best place to do this 
from my perspective.

-- 
Bruno


On 14 October 2021 13:59:01 BST, John David  wrote:
>While researching some SIFT, SURF, and ORB implementations and support on 
>Gentoo I came across a request for maintenance support 
>for autopano-sift-c.  I have been in contact with the Gentoo Proxy 
>Maintainers about maintaining that and other packages in the portage tree.
>
>While researching background I read that autopano-sift-c is a port of an 
>original C# code base, but what is probably less well known is that the 
>original C# code (circa 2004) does not appear to be available anymore, and 
>the original developer of the C# code (Sebastian Nowozin)  has no interest 
>in maintaining it.  Since it is a port of orphaned code I am not sure that 
>maintaining autopano-sift-c is viable in the long term.
>
>I am exploring the following options, I can work with the hugin folks to 
>maintain the original autopano-sift-c code, or I can work on modifying 
>hugin to use a different library.  
>
>For long term support and longevity, porting to use a different library 
>would likely be the most maintainable, but before spending a bunch of time 
>on this I would like to know if there would be support from both the 
>developers and the community.  No reason to waste your time or mine if that 
>is a non-starter.  If this is a viable option I would be interested to hear 
>what other libraries that others have used and would interested to see 
>supported.  At the moment I am looking into OpenCL and OpenCV libraries, 
>but am open to anything that is actively maintained and have a chance of 
>being so in the long term.

-- 
A list of frequently asked questions is available at: 
http://wiki.panotools.org/Hugin_FAQ
--- 
You received this message because you are subscribed to the Google Groups 
"hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion on the web visit 
https://groups.google.com/d/msgid/hugin-ptx/B93A609F-C256-404C-9387-FCB284B62875%40postle.net.

Reply via email to