ee.Image.gt

AI-generated Key Takeaways

• This function compares bands of two images element-wise, returning 1 if the first value is greater than the second, and 0 otherwise.

• Band matching is done pairwise, by position if names differ but count is the same, or one-to-many if one image has a single band.

• The output image has boolean pixel types and band names derived from the longer input image, or image1 if lengths are equal.

Returns 1 if and only if the first value is greater than the second for each matched pair of bands in image1 and image2. If either image1 or image2 has only 1 band, then it is used against all the bands in the other image. If the images have the same number of bands, but not the same names, they're used pairwise in the natural order. The output bands are named for the longer of the two inputs, or if they're equal in length, in image1's order. The type of the output pixels is boolean.

Usage	Returns
Image.gt(image2)	Image

Argument	Type	Details
this: image1	Image	The image from which the left operand bands are taken.
image2	Image	The image from which the right operand bands are taken.

Examples

Code Editor (JavaScript)

// Show world oceans in blue and anything higher than the ellipsoid as gray.
// The bedrock layer is generally close to the geoid (sealevel).
var elevation = ee.Image('NOAA/NGDC/ETOPO1').select('bedrock');
var waterLand = elevation.gt(0.0);
var waterLandViz = {palette: ['cadetblue', 'lightgray']};
Map.addLayer(waterLand, waterLandViz, 'water_land');

Python setup

See the Python Environment page for information on the Python API and using geemap for interactive development.

import ee
import geemap.core as geemap

Colab (Python)

# Show world oceans in blue and anything higher than the ellipsoid as gray.
# The bedrock layer is generally close to the geoid (sealevel).
elevation = ee.Image('NOAA/NGDC/ETOPO1').select('bedrock')
water_land = elevation.gt(0.0)
water_land_viz = {'palette': ['cadetblue', 'lightgray']}
m = geemap.Map()
m.add_layer(water_land, water_land_viz, 'water_land')
m