How to Create a Custom Filter to Filter by Band Name Existence in Earth Engine?

Digging Through Data? How to Find the Right Bands in Earth Engine

So, you’re diving into Google Earth Engine (GEE), huh? It’s like this massive playground of satellite imagery, and you’re trying to find that one specific toy – or, in this case, that one specific band in an image. GEE’s got a ton of tools, but sometimes you need to get a little creative to wrangle your data. Ever been there? I know I have.

The thing is, image collections in GEE can be a real mixed bag. You’ve got data from different satellites, different time periods, and sometimes, the band names are just… different. Imagine searching for “red” and finding out it’s called “band4” in one image and “B4” in another. Frustrating, right? That’s why filtering by band name existence is so important. You don’t want to miss out on valuable data just because of a naming quirk.

Luckily, GEE gives you a neat way to see what band names an image actually has: the system:band_names property. Think of it as a list of ingredients for each image.

Now, instead of trying to build some crazy custom filter from scratch, there’s a simpler way. You can use ee.Filter.listContains. It’s like asking, “Hey, does this list have this in it?”

Let me give you a quick example. Say you’re working with Sentinel-2 data and you need the near-infrared band, which is often called ‘B8’. Here’s how you’d filter your image collection:

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