geodata.mask.trim_raster
========================

.. py:function:: geodata.mask.trim_raster(raster: rasterio.DatasetReader) -> rasterio.DatasetReader

   Remove the all-zero columns and rows at the border of the raster and returns the trimmed raster.
   This method does not remove the all-zero cols or rows in the middle of the valid values.

   For example: if the raster.read(1) (the array values) is the following::

       np.array(
           [
               [0, 0, 9, 0, 0, 0, 0],
               [0, 0, 1, 2, 0, 0, 0],
               [0, 0, 2, 3, 4, 0, 0],
               [0, 0, 0, 0, 0, 0, 0],
               [0, 0, 1, 0, 0, 0, 0],
               [0, 0, 0, 0, 0, 0, 0],
           ]
       )

   The bounds of valid values will be (2, 4, 0, 4);
   The all zero columns and rows at the border of the array will be removed.

   :param raster: The source raster
   :type raster: ras.DatasetReader

   :returns: The trimmed raster.
   :rtype: ras.DatasetReader