# pydicom.config.overlay_data_handlers

`pydicom.config.``overlay_data_handlers` = [<module 'pydicom.overlay_data_handlers.numpy_handler' from '/build/pydicom-HOuqyn/pydicom-1.4.1/pydicom/overlay_data_handlers/numpy_handler.py'>]

  Handlers for converting (60xx,3000) Overlay Data

  New in version 1.4.

  This is an ordered list of Overlay Data handlers that the `overlay_array()` method will use to try to extract a correctly sized numpy array from an Overlay Data element.

  Handlers shall have three methods:

  def supports_transfer_syntax(ds)
    Return `True` if the handler supports the transfer syntax indicated in `Dataset` ds, `False` otherwise.
  def is_available():
    Return `True` if the handler’s dependencies are installed, `False` otherwise.
  def get_overlay_array(ds, group):
    Return a correctly shaped `numpy.ndarray` derived from the Overlay Data with element tag group, in `Dataset` ds or raise an exception.

  The first handler that both announces that it supports the transfer syntax and does not raise an exception is the handler that will provide the data.

  If all handlers fail to convert the data only the last exception is raised.

  If none raise an exception, but they all refuse to support the transfer syntax, then a `NotImplementedError` is raised.