[pypy-dev] Questions about build new extension with RPython

[Armin Rigo]

Hi Boxiang,

On 21 June 2015 at 01:33, Boxiang Sun <daetalusun at gmail.com> wrote:
> Does it mean if wrap OpenCV in PyPy
> with cffi. OpenCV-PyPy could not use ndarray?

I don't know OpenCV myself, but writing a CFFI module accessing it
should be easy, even if there are functions that take numpy arrays.
You can do:

    ffi.from_buffer(some_ndarray)

which returns a ffi ``char *`` pointer, pointing to the data from the
ndarray.  You can pass this raw pointer to C functions from OpenCV.
There is no copy of the data; if the C function modifies the data, it
will be modified in the numpy array too.


A bientôt,

Armin.