Output Formats


Output formats control how results are stored – like GeoTIFF, JSON, etc. You can use output destinations, which control where the results are stored, in conjunction with output formats.

For example, with format='geotiff' you might use destination='email@example.com' or destination='download'. Both would produce GeoTIFFs; one would send an email with a link to the file, and the other would download the GeoTIFF within your script.

Some output formats are required by certain destinations. For example, with the Catalog destination, you can only use the GeoTIFF format.

When calling compute, you can pick the output format for the results using the format argument. The supported formats are “pyarrow” (default), “geotiff”, “json”, and “msgpack”.

If you don’t need to supply any options for the formatter, you can pass the format name as a string:

>>> two = wf.Int(1) + 1
>>> two.compute(format="json")

If you would like to provide more format options, you pass the format as a dictionary:

>>> two = wf.Int(1) + 1
>>> two.compute(format={"type": "pyarrow", "compression": "brotli"})

Note that when passing the format as a dictionary, it must include a type key with the format’s name.

The results will be returned differently depending on the format specified. When using the “pyarrow” format, results will be deserialized and unpacked into Result Types. For all other formats, the results will not be deserialized and will be returned as raw bytes.

Available Formats

The following is a list of the available formats and their options. The keys in the format dictionary must match the keys listed here.


Shorthand: "pyarrow"

PyArrow (the default) is the best format for loading data back into Python for further use. It’s fast and memory-efficient, especially for NumPy arrays, and also automatically unpacks results into Result Types.

  • compression: the type of compression used for the data (string, default “lz4”, one of “lz4” or “brotli”)


Shorthand: "geotiff"

GeoTIFF is the best format for using raster data with other geospatial software, such as ArcGIS or QGIS. Only Image objects can be computed in GeoTIFF format. GeoTIFF data is returned in raw bytes, so in most cases, you’ll want to write the data out to a file (use the file= parameter to compute for this).

  • overviews: whether to include overviews; overview levels are calculated automatically (bool, default True)
  • tiled: whether to create a tiled GeoTIFF (bool, default True)
  • compression: the compression to use (string, default “LZW”, one of “LZW”, “None”, or “JPEG”)
  • overview_resampler: the resampler to use for calculating overviews (string, default “nearest”, one of “nearest”, “average”, “bilinear”, “cubic”, or “mode”)


Shorthand: "json"

JSON is the best format for using the data in other languages because it is language-independent.

  • No options


Shorthand: "msgpack"

MsgPack is similar to JSON. It is a good format for using the data in other languages, but it is faster and smaller than JSON, especially for NumPy Arrays. Note that array data (Array, Image, etc.) is encoded in raw bytes using the msgpack-numpy library, so msgpack is only recommended for use with Python when computing data containing arrays.

  • No options