Rasterio: Use case for src.meta vs. src.profile when reading and writing rasters?

Question

When I read a raster in with rasterio (version 0.36.0) in Python, I can call up the metadata in two ways:

src = rasterio.open(my_raster)

src.profile

{'affine': Affine(1.0, 0.0, 401900.0, 0.0, -1.0, 7620200.0),
'count': 1,  'crs': CRS({'init': 'epsg:32606'}),  'driver': 'GTiff',
'dtype': 'float32',  'height': 11100,  'interleave': 'band',
'nodata': -9999.0,  'tiled': False,
'transform': (401900.0, 1.0, 0.0, 7620200.0, 0.0, -1.0),  'width': 13750}

src.meta

{'affine': Affine(1.0, 0.0, 401900.0, 0.0, -1.0, 7620200.0),
'count': 1,  'crs': CRS({'init': 'epsg:32606'}),  'driver': 'GTiff',
'dtype': 'float32',  'height': 11100,  'nodata': -9999.0,
'transform': (401900.0, 1.0, 0.0, 7620200.0, 0.0, -1.0),  'width': 13750}

The results are quite similar, but profile stores a little more information such as the tiling and interleave information. Which of these methods is a better practice for retrieving metadata? Are there examples where one is better than the other? Both 'meta' and 'profile' seem to work fine right now for writing the single band float32 raster I am working with.

Answer 1

The meta property contains the basic raster metadata. The profile property is a super set of meta which includes dataset creation options (i.e inc. tiling, block size, compression etc...).

You would use src.profile when you want to ensure you create an exact (empty) clone of an existing dataset. And it is especially useful when you are reading in block windows from a very large raster, then writing the chunks back out to your new raster as it is a lot faster if the input and output rasters have the same block layout.

Further info:

• https://github.com/mapbox/rasterio/pull/406#issuecomment-119010268
• https://github.com/mapbox/rasterio/issues/405