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I am very new to the Google Earth Engine and found that it is a powerful tool in satellite images processing. I want to separate the land and water part in Sentinel-2 images and work only on the water part.
What should I do to solve this problem?
I am working with the image below:
var image= ee.Image('COPERNICUS/S2_SR/20210619T031541_20210619T032742_T48QYJ');
var visualization = {gain:'0.1,0.1,0.1',scale:5};
Map.addLayer(image,visualization,'1906');
Sentinel 2A Data includes a Scene Classification (SCL) which already classifies the images in some very basic classes. Keep in mind, that this classification is in no way perfect, but it should give you a good and quick starting point.
To use it, you would mask the sentinel image by the appropriate value in the SCL. For the values see this page all the way at the bottom.
var image= ee.Image('COPERNICUS/S2_SR/20210619T031541_20210619T032742_T48QYJ');
var mask_land = image.updateMask(image.select('SCL').eq(6))
var visualization = {gain:'0.1,0.1,0.1',scale:5};
Map.addLayer(mask_land,visualization,'1906');
To mask it we first select the Scene Classification band and then build a binary mask, where every pixel that's equal to 6 (which is water) gets a one, and every pixel not equal to 6 gets a 0.
