vlc.VideoLockCb
===============

.. py:class:: vlc.VideoLockCb

   Bases: :py:obj:`ctypes.c_void_p`


   Callback prototype to allocate and lock a picture buffer.

   Whenever a new video frame needs to be decoded, the lock callback is
   invoked. Depending on the video chroma, one or three pixel *planes* of
   adequate dimensions must be returned via the second parameter. Those
   planes must be aligned on 32-bytes boundaries.

   :param opaque: private pointer as passed to :func:`libvlc_video_set_callbacks` [IN].
   :param planes: start address of the pixel planes (LibVLC allocates the array.
       of void pointers, this callback must initialize the array) [OUT].

   :return: a private pointer for the display and unlock callbacks to identify.
       the picture buffers.

   Initialize self.  See help(type(self)) for accurate signature.