Earth Engine Downloader

This code downloads all images in an image collection from Earth Engine to a specified folder. It can be called from the command line or a Python module.

Installation

This library requires you have set up access to Earth Engine via its Python API and already authenticated your account. See here for more information on how to do that. If you're on Windows, I recommend using Bash on Windows for this project, but won't detail that further here - the installation instructions below assume a bash prompt.

Dependencies

The only dependency for this script, besides the Earth Engine Python API is pycurl for downloading the images. pycurl requires some system setup.

sudo apt-get install libcurl4-openssl-dev
sudo pip install pycurl

You may also need to install PIL if it wasn't installed when you set up the Earth Engine API. Download the latest source kit, then do something like the following

tar -xzvf .\Imaging-1.1.7.tar.gz
cd Imaging-1.1.7
python setup.py install

You have to install the development package for curl before pycurl will compile. The above commands should handle installation.

Command line usage

If you call the script on the command line, it has three simple, positional parameters:

1. The path or identifier of the ImageCollection to downloading
2. The output folder on the local machine to save images into
3. The maximum number of images to download

python ee_download.py "users/yourusername/path/to/image/collection" "/mnt/c/myusername/path/to/outputs" 9999

Usage in Python

After installation, you can import the module and call the main functions - parameters to the bulk downloader are the same as the command line usage above

import ee_download
downloaded_images = ee_download.download_images_in_collection(
		collection_id = "users/yourusername/path/to/image/collection",
		output_folder = "/mnt/c/myusername/path/to/outputs",
		max_items = 9999
)

Alternatively, if you just want to use the single image downloading mechanism, you can run

downloaded_images = ee_download.download_image_by_asset_path(
		asset_path = "users/yourusername/some/single/image",
		output_folder = "/mnt/c/myusername/path/to/outputs",
)

Each function returns the full paths to the downloaded items as a list.