ee.Image.changeProj

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Examples

Tweaks the projection of the input image, moving each pixel from its location in srcProj to the same coordinates in dstProj.

Usage	Returns
`Image.changeProj(srcProj, dstProj)`	Image

Argument	Type	Details
this: `input`	Image
`srcProj`	Projection	The original projection.
`dstProj`	Projection	The new projection.

Examples

Code Editor (JavaScript)Colab (Python)

// A DEM image object.
var img = ee.Image('MERIT/DEM/v1_0_3');

// Construct a projection object from a WKT string or EPSG code, for example,
// the Robinson projection (https://epsg.io/54030).
var proj = ee.Projection(
  'PROJCS["World_Robinson",' +
      'GEOGCS["GCS_WGS_1984",' +
          'DATUM["WGS_1984",' +
              'SPHEROID["WGS_1984",6378137,298.257223563]],' +
          'PRIMEM["Greenwich",0],' +
          'UNIT["Degree",0.017453292519943295]],' +
      'PROJECTION["Robinson"],' +
      'UNIT["Meter",1]]'
)
// Optionally adjust projection scale; stretch layer larger in this case.
.scale(0.9, 0.9);

// "Paint" the image in the desired projection onto the projection of
// the map canvas ('EPSG:3857').
var imgProj = img.changeProj(proj, 'EPSG:3857');

// Add an overlay image to the map to cover the default base layers.
Map.setCenter(0, 0, 2);
Map.addLayer(ee.Image(1), {palette: 'grey'}, 'Grey background', false);

// Add the projection-tweaked image to the map.
Map.addLayer(imgProj, {min: 0, max: 3000}, 'DEM in Robinson projection');

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

# A DEM image object.
img = ee.Image('MERIT/DEM/v1_0_3')

# Construct a projection object from a WKT string or EPSG code, for example,
# the Robinson projection (https://epsg.io/54030).
proj = (
    ee.Projection(
        'PROJCS["World_Robinson",'
        + 'GEOGCS["GCS_WGS_1984",'
        + 'DATUM["WGS_1984",'
        + 'SPHEROID["WGS_1984",6378137,298.257223563]],'
        + 'PRIMEM["Greenwich",0],'
        + 'UNIT["Degree",0.017453292519943295]],'
        + 'PROJECTION["Robinson"],'
        + 'UNIT["Meter",1]]'
    )
    # Optionally adjust projection scale stretch layer larger in this case.
    .scale(0.9, 0.9)
)

# "Paint" the image in the desired projection onto the projection of
# the map canvas ('EPSG:3857').
img_proj = img.changeProj(proj, 'EPSG:3857')

# Add an overlay image to the map to cover the default base layers.
m = geemap.Map()
m.set_center(0, 0, 2)
m.add_layer(ee.Image(1), {'palette': 'grey'}, 'Grey background', False)

# Add the projection-tweaked image to the map.
m.add_layer(
    img_proj,
    {'min': 0, 'max': 3000},
    'DEM in Robinson projection',
)
m