Haskell OpenCV-3.1 binding

This is a Haskell library providing a binding to OpenCV-3.1. It binds directly with the C++ API using the inline-c Haskell library.

The library is far from complete but the framework is there to easily bind missing functionality.

Documentation

The project hasn't been released to Hackage yet so you won't find any documentation there. Instead, we've uploaded the docs to our website.

Examples

The documenation includes example programs that are automatically extracted from the source code and run as part of the test-suite. See the opencv-doc-images test-suite. The resulting images are referenced from the Haddock documentation.

Development

We use Nix to enter an environment containing all the needed dependencies. For the moment the following commands only work on Linux. The Nix expression for OpenCV-3.1 currently fails to build on OS X.

curl https://nixos.org/nix/install | sh   # Only execute this if you haven't installed Nix yet.
nix-shell

Then you should be able to use cabal as normal.

Contributing

We love to get contributions! Please send us your pull requests. Do make sure your PR comes with Haddock documentation and preferably with an example program. If you include your example program in the following way:

{- | ...

Example:

@
myExampleImg :: Mat (ShapeT [200, 300]) ('S 4) ('S Word8)
myExampleImg = ...
@

<<doc/generated/examples/myExampleImg.png myExampleImg>>
-}

then run cabal test, now your Haddock documentation will include a nice picture with the output of your program. Not only that, but your example program will at the same time function as a test for the function you just documented!

Policies

In haskell-opencv we use the most precise types for integer arguments. OpenCV uses int which is a 32-bit integer. So in Haskell we have to use Int32 instead of Int for, eg. width and height.