Image.py 文件源码

def filter(self, filter):
        """
        Filters this image using the given filter.  For a list of
        available filters, see the :py:mod:`~PIL.ImageFilter` module.

        :param filter: Filter kernel.
        :returns: An :py:class:`~PIL.Image.Image` object.  """

        self.load()

        if isinstance(filter, collections.Callable):
            filter = filter()
        if not hasattr(filter, "filter"):
            raise TypeError("filter argument should be ImageFilter.Filter " +
                            "instance or class")

        if self.im.bands == 1:
            return self._new(filter.filter(self.im))
        # fix to handle multiband images since _imaging doesn't
        ims = []
        for c in range(self.im.bands):
            ims.append(self._new(filter.filter(self.im.getband(c))))
        return merge(self.mode, ims)