google-earth-engine – Clipping a GEE Image with the Python API

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I am looking for a way to clip image collection by a given polygon geometry with Python API,

The GEE JavaScript equivalent is simply ImageCollection.clip(geom)
(https://developers.google.com/earth-engine/image_visualization#clipping)

With the python API I get the error: 'ImageCollection' object has no attribute 'clip'.

I'm adding my code after using .mean() as a reducer

My code:

set the boundary polygon

my_boundary = ee.Geometry.Polygon([ [[-5, 40],[65, 40],[65, 60],[-5, 60],[-5, 60]]] ,proj=None)

#set the ImageCollection and Image
img_Collection = ee.ImageCollection('COPERNICUS/S5P/NRTI/L3_NO2').filterDate('2020-03-01', '2020-03-27').select('NO2_column_number_density')

my_Image=img_Collection.mean().clip(my_boundary)

#Create Ipyleaflet map
my_map = ipyleaflet.Map(zoom=7)

my_map.add_layer(layer=my_Image)

my_map

error:
AttributeError: 'Image' object has no attribute 'model_id'

Best Answer

No matter the API, clip() is a function on images, but not image collections. So in order to do it, you have to either turn your ImageCollection into an Image using reducers like mean(), mosaic() etc. or map clipping procedure over your ImageCollection, i.e.

imageCollection.map(function(image) { return image.clip(geometry); });

In pyhton API, use lambda function in such case.

Related Solutions

Google Earth Engine – How to .map Reproject on Image Collection with Python API

The crsTransform argument cannot be the string 'null'. You either leave it out completely, set it to None, or specify a proper value.

# Just a collection with 10 random images as a dummy setup
collection = ee.ImageCollection( 
  ee.List.sequence(1, 10).map(lambda i: ee.Image.random(i))
)

def imreproj(image):
    return image.reproject(crs='EPSG:4326', scale=1000)

reprojected = collection.map(imreproj)

GEE Python API – Temporally Reduce Image Collection from Daily to Monthly Using map()

I don't think there's a way to call GEE's map() function with a class method. Since the functions that can be used in a map() can take only 1 argument, but class methods will have self passed on to it in addition.

You can re-structure your code to something like below

def temp_reduce_image_coll(self):
    
    def temp_reduce_image(dr):
        start = ee.DateRange(dr).start()  # get the start time of given date range
        end = ee.DateRange(dr).end()     # get the end time of given date range
    
        mimages = self.iColl.filter(ee.Filter.date(start,end)).select(0)  # filter a single month
        mimages_reduced = mimages.reduce(ee.Reducer.sum())             # apply reducer
        mimages_reduced = mimages_reduced.set(               # set start and end times to reduced image
            'system:time_start', start.millis()).set(
            'system:time_end', end.millis())

        return ee.Image(mimages_reduced)                     # return reduced image
        
    self.iColl_reduced = self.drl.map(temp_reduce_image)
    print(self.iColl_reduced.size().getInfo())
    return self.iColl_reduced

set the boundary polygon

Best Answer

Related Solutions

Google Earth Engine – How to .map Reproject on Image Collection with Python API

GEE Python API – Temporally Reduce Image Collection from Daily to Monthly Using map()

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