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[Offline imagery] Offline download of Earth Engine assets

Open gino-m opened this issue 1 year ago • 7 comments

Simplify process of offline imagery creation and allow and Earth Engine asset to be downloaded offline. The process might work as follows:

  • An asset ID and service account credentials will be needed.
  • getPixels can be called to fetch high-res images, which are sliced into tiles and stored on the device
  • Images are downsampled on device as they're downloaded and stored separately.

If we want this to be more broadly applicable this could also be built into its own app (Flutter?) which could download data to a shared location accessible by Ground.

gino-m avatar Nov 14 '24 19:11 gino-m

During a demo today, interest in displaying own background maps was signaled again.

jo-spek avatar Feb 14 '25 15:02 jo-spek

During a demo today, interest in displaying own background maps was signaled again.

In what format(s)?

gino-m avatar Feb 14 '25 15:02 gino-m

No specifics were mentioned, but I assume GeoTIFFs. Google Earth Engine assets were also well received as an option.

jo-spek avatar Feb 19 '25 17:02 jo-spek

No specifics were mentioned, but I assume GeoTIFFs. Google Earth Engine assets were also well received as an option.

If the data can be written as COGs with the right tiling then this can be done fairly easily.

If instead we want an arbitrary image to be downloaded from Earth Engine assets, either the user would need to sign into Earth Engine on the device, or would need to grant read access to an FAO-owned service account.

gino-m avatar Feb 19 '25 18:02 gino-m

If the data can be written as COGs with the right tiling then this can be done fairly easily.

How would the COGs be integrated? From the survey organizer's side?

jo-spek avatar Feb 19 '25 18:02 jo-spek

How would the COGs be integrated? From the survey organizer's side?

If they're provided by the organizers then yes, we'd have to add a UI for them to manage them. If they're system-wide (ie for all users), then you can probably get away with updating the config in the db manually.

gino-m avatar Feb 19 '25 18:02 gino-m

Documentation and blog from Collect Earth Online might be helpful here

jabramowitz5 avatar Jun 26 '25 16:06 jabramowitz5