ALE Quick Start

This document provides a set of steps to get setup for generating Image Support Data (ISD) for an image.

Installation

The easiest way to setup ALE is using Anaconda. Once you have Anaconda or Miniconda installed install ALE from conda-forge by running

conda install -c conda-forge ale

Note

It is highly recommended that you use environments to manage the packages you install with Anaconda.

Data

Planetary imagery is not archived with sufficient data to generate an ISD from only the image and its label. ALE currently supports two supplementary data sources: ISIS cubes with attached SPICE, and NAIF SPICE Kernels.

If you are working with ISIS cubes that have attached SPICE (the spiceinit application has been run on them) then ALE will use the data embedded in the cube file.

If you are working with PDS3 images or ISIS cubes that do not have attached SPICE, then you will need to download the required NAIF SPICE Kernels for your image. It is recommended that you use the metakernels provided in the PDS kernel archives. You can specify the path for ALE to search for metakernels via the ALESPICEROOT environment variable. This should be set to the directory where you have the PDS kernel archives downloaded. An example structure would be

• $ALESPICEROOT

  • mro-m-spice-6-v1.0

  • dawn-m_a-spice-6-v1.0

  • mess-e_v_h-spice-6-v1.0

See ale.base.data_naif.NaifSpice.kernels for more information about how to specify NAIF SPICE kernels.

Load/Loads

The ale.drivers.load() and ale.drivers.loads() functions are the main interface for generating ISDs. Simply pass them the path to your image file/label and they will attempt to generate an ISD for it.

import ale

image_label_path = "/path/to/my/image.lbl"
isd_string = ale.loads(image_label_path)