3

Under scale, Google Earth Engine (GEE) mentions that:

For continuous valued images, the pixel values of upper levels of the pyramid are the mean of pixels at the next lower level. For discrete valued images, pixel values of upper levels of the pyramid are a sample (usually the top left pixel) of pixels at the next lower level.

But under Pyramiding policy, it clearly says that MODE, MIN, MAX, are also possible options.

I am deducing out of this that Google uploaded assets, so everything in the Data Catalog is using either MEAN or SAMPLE. Is this true? How can one check what pyramiding policy was used for a specific asset?

Also, is it true that for user uploaded imagery, the user must keep track of what policy they used during ingestion? What about datasets that are under some projects that are not available in the catalog, but they are still popular, such as GLAD How can one determine the pyramiding policy of such datasets?

I am aware that I can reverse engineer the image to learn what pyramiding scheme was used, but I am asking if there is any straight forward method for doing it.

Some datasets that I am trying to determine the pyramiding policy for are:

ee.Image("projects/glad/GLCLU2020/Forest_type")
ee.Image("ESA/VITO/Brockmann Consult/CS/GAMMA Remote Sensing/IIASA/WUR")
ee.Image("AHN/AHN2_05M_INT")

1 Answer 1

1

You can use Earth Engine Python API command line: "earthengine asset info <asset_id>" to get an asset's pyramid policy.

1
  • it is worth mentioning that if <asset_id> is an ImageCollection, the pyramiding policy won't be given, you need to add the specific image you want. Compare earthengine asset info projects/JRC/TMF/v1_2022/DeforestationYear/ with earthengine asset info projects/JRC/TMF/v1_2022/DeforestationYear/1AFR
    – Matifou
    Nov 4, 2023 at 13:12

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.