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I want to clip an image by a feature collection (roi shapefile) and export it as TIFF. When I add the clipped image to Map, it shows exactly what I want with only values inside the roi showing. But when I export it to GeoTIFF, it clips the image to bounding box of the roi rather than actual roi borderlines.

IMERG = ee.ImageCollection('NASA/GPM_L3/IMERG_MONTHLY_V06').first().select('precipitation')
clip = IMERG.clipToCollection(roi)  #roi is a feature collection
geemap.ee_export_image(clip, filename='test2.tif', scale=11132, region=roi.geometry())

This is what it exports This is what it exports

This is what I would like (obtained by clipping the exported image by country shapefile again in QGIS).
This is what I would like

This question also asks pretty much the same thing but don't seem to have a proper answer to this issue although an answer is accepted.

1 Answer 1

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Using .clip() should work

import json

## load geojson of region of interest
gjson_path = r"C:\Users\Matt\Documents\roi.geojson"

with open(gjson_path) as f:
    gjson = json.load(f)

## get gjson features
features = gjson['features']

## make Earth Engine FeatureCollection of features
fc = ee.FeatureCollection(features)

## get image
IMERG = ee.ImageCollection('NASA/GPM_L3/IMERG_MONTHLY_V06').first().select('precipitation')

## clip image
clip = IMERG.clipToCollection(fc)  # fc is a feature collection

## export result
region = fc.geometry()
scale = 50
folder = 'test folder'
img_name = 'test_img'

export_config = {'scale': scale, 'maxPixels': 1.0E13, 'driveFolder': folder, 'region': region}

task = ee.batch.Export.image(clip, img_name, export_config)
task.start()

enter image description here

6
  • No, it doesn't work. Don't think there is much difference between these two anyway, clipToCollection is for more complex geometries.
    – Moon Child
    Sep 16, 2021 at 11:27
  • .clip() is what I use and it works as expected, but then I don't use the geemap wrapper. does removing .geometry() from roi.geometry() work? Perhaps it is exporting with regards to the bounding box, rather than the features themselves.
    – Matt
    Sep 16, 2021 at 11:40
  • roi is a FeatureCollection but the export function requires Geometry object. That is why I did roi.geometry . The other question I linked to also gets the same results although done from GEE code editor so don't think there's any problem in geemap.
    – Moon Child
    Sep 16, 2021 at 11:50
  • I updated my answer with the code I used to clip with a feature collection and export to Drive. I wonder then if your issue is caused by how your feature collection was constructed.
    – Matt
    Sep 16, 2021 at 13:47
  • hmmm.. the feature collection I used is actually a shapefile of country map. I used the following code to convert it into a feature collection: shp = '/MyDrive/country.shp' roi = geemap.shp_to_ee(shp)
    – Moon Child
    Sep 16, 2021 at 14:08

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