OpenCV binding

OpenCV binding

[Andy Tai]

curious if there is OpenCV binding for guile?  and anything like NumPy
for guile?

Re: OpenCV binding

[David Pirotte]

[-- Attachment #1: Type: text/plain, Size: 1021 bytes --]

Hello Andy,

> curious if there is OpenCV binding for guile?  and anything like NumPy
> for guile?

No, and currently that would not be possible, as Open-CV is written in
C++ and there no ffi for C++ code ... They used to have and maintain a
C api, up to 2.xx (not sure up to what exact version), then dropped
support for the C api.

This is why - not the only reason, but a major factor in my decision -
I choose to bind and extend Guile-CV [1] using Vigra [2], but now Vigra
seems unmaintained :(

You also might look at aiscm [3], and other projects that might interest
you, to my knowledge, the most up-to-date guile projects list is here
[4].

David

[1]	https://www.gnu.org/software/guile-cv/
[2]	http://ukoethe.github.io/vigra/

	it actually is because someone was maintaining a Vigra C lib
	that I could use Vigra in Guile-CV, as Vigra is also written in
	C++

	https://github.com/BSeppke/vigra_c

[3]	https://github.com/wedesoft/aiscm
[4]	http://sph.mn/foreign/guile-software.html

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: OpenCV binding

[Hans Åberg]

> On 8 Sep 2022, at 19:54, David Pirotte <david@altosw.be> wrote:
> 
>> curious if there is OpenCV binding for guile?  and anything like NumPy
>> for guile?
> 
> No, and currently that would not be possible, as Open-CV is written in
> C++ and there no ffi for C++ code ...

I wrote a C++ wrap for Guile, and the opposite is also possible with GCC, only that C++ exceptions do not work properly:
https://lists.gnu.org/archive/html/guile-user/2010-05/msg00035.html

Re: OpenCV binding

[Andy Tai]

As a follow-up to this, some recent bindings for OpenCV to other
languages use "unofficial" (not OpenCV supported) C bindings generated
by the binding authors themselves to bind... for example Go's gocv
contains C APIs generated from using libclang to parse OpenCV C++
headers and these C APIs are then used for bindings to Go, and D.

I read that Java and Python OpenCV bindings were also made this way
but I did not confirm them.

Wonder if this is the way to go for accessing modern OpenCV from guile?

On Thu, Sep 8, 2022 at 11:59 AM Hans Åberg <haberg-1@telia.com> wrote:
>
>
> > On 8 Sep 2022, at 19:54, David Pirotte <david@altosw.be> wrote:
> >
> >> curious if there is OpenCV binding for guile?  and anything like NumPy
> >> for guile?
> >
> > No, and currently that would not be possible, as Open-CV is written in
> > C++ and there no ffi for C++ code ...
>
> I wrote a C++ wrap for Guile, and the opposite is also possible with GCC, only that C++ exceptions do not work properly:
> https://lists.gnu.org/archive/html/guile-user/2010-05/msg00035.html
>
>