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I am trying to follow the instructions in- Sentinel-2 L2A and scripts from- Examples for S2L2A but these codes do not have an option to download S2 images with an option of cloud cover. I want to download time series S2 image over a bounding box but the images that are used to clip over bb should not have a cloud cover % more than 5. How do I include cloud cover condition before download?

Hi, it is very simple to add a cloud cover filter to your request payload. If you are working with Python you can add a cloud cover % (calculated for the full tile) like this:


request = SentinelHubRequest(

    evalscript=evalscript,

    input_data=[

        SentinelHubRequest.input_data(

            data_collection=DataCollection.SENTINEL2_L2A,          

            time_interval=('2023-05-14', '2023-06-14'),          

            other_args={"dataFilter": {"maxCloudCoverage": 50}}

        )

As you can see it is inserted in other_args. As you also mentioned downloading multiple dates in your request, I would recommend reading this material about how to do this in evalscripts using the preProcessScenes function in our documention.


For example, you can use it to request a time series of values for a single band like in the below example:


//VERSION=3

// Script to extract a time series of Band 5 values using 

// Sentinel 2 Level 2A data and  metadata file.

function setup() {

  return {

    input: [{

      bands: ["B05"],

      units: "DN"

    }],

    output: {

      id: "S2_L2A",

      bands: 1,

      sampleType: SampleType.UINT16

    },

    mosaicking: Mosaicking.ORBIT

  }

}



// The following function is designed to update the number of

// output bands without knowing beforehand how many there are

function updateOutput(outputs, collection) {

    Object.values(outputs).forEach((output) => {

        output.bands = collection.scenes.length;

    });

}



function evaluatePixel(samples) {

  // Precompute an array to contain B05 observations

  var n_observations = samples.length;

  let band_05 = new Array(n_observations).fill(0);

  

  // Fill the array

  samples.forEach((sample, index) => {

    band_05[index] = sample.B05;

  });

                     

  return band_05;

}

Hope that this information helps you out 🙂

Hey, what is the difference between- If mosaicking is ORBIT: and If mosaicking is TILE: taking above codes as an example.

To put it very simply;


TILE will use every acquisition in the time period you requested whereas ORBIT will only select one acquisition from each Orbit. This is explained in more detail here.

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