Sentinel 2 download script

[rickus7.swanepoel (Rickus Swanepoel)]

I am having trouble with downloading the S2 L2A bands see below my request script. The request runs but it returns an empty image when I open it in ArcMap?

Your assistance is appreciated, I just removed the Bearer token.

curl -X POST https://services.sentinel-hub.com/api/v1/process \
 -H 'Content-Type: multipart/form-data' \
 -H 'Authorization: \
 --form-string 'request={
  "input": {
    "bounds": {
      "geometry": {
        "type": "Polygon",
        "coordinates": [
          [
            [
              387586.974469,
              8098945.900398
            ],
            [
              387884.086646,
              8097476.83939
            ],
            [
              389674.763248,
              8097959.748413
            ],
            [
              389409.287272,
              8099351.638973
            ],
            [
              387586.974469,
              8098945.900398
            ]
          ]
        ]
      },
      "properties": {
        "crs": "http://www.opengis.net/def/crs/EPSG/0/32737"
      }
    },
    "data": [
      {
        "dataFilter": {
          "timeRange": {
            "from": "2023-06-16T00:00:00Z",
            "to": "2023-06-16T23:59:59Z"
          },
          "mosaickingOrder": "mostRecent"
        },
        "type": "sentinel-2-l2a"
      }
    ]
  },
  "output": {
    "width": 104.12118271595553,
    "height": 93.89618236811039,
    "responses": [
      {
        "identifier": "default",
        "format": {
          "type": "image/tiff"
        }
      }
    ]
  }
}' \
 --form-string 'evalscript=//VERSION=3

function setup() {
  return {
    input: [
      {
        bands: ["B01","B04","B07","B09","B02","B05","B08","B11","B03","B06","B12","B8A"],      
        units: "REFLECTANCE",            
      }
    ],
    output: [
      {
        id: "default",
        bands: 12,
        sampleType: "UINT16",        
        noDataValue: 0,
      },    
    ],
    mosaicking: "SIMPLE",
  };
}


function evaluatePixel(sample) {
    let val = [sample.B01, sample.B02, sample.B03, sample.B04, sample.B05, sample.B06, sample.B07, sample.B08, sample.B8A, sample.B09, sample.B11, sample.B12];
    return val;
}

'

[william.ray]

Hi Rickus,

Thanks for the question, for Sentinel-2 optical data, the relation between DN and REFLECTANCE (default unit) is: DN = 10000 * REFLECTANCE so in your evalscript you need to multiply each sample.[BAND] by 1000 to return the surface reflectance data in UINT16 format. For more info, I recommend reading this part of the docs.

Below is also the correct evalscript which will return an image for you!

//VERSION=3
function setup() {
  return {
    input: [
      {
        bands: ["B01","B04","B07","B09","B02","B05","B08","B11","B03","B06","B12","B8A"],      
        units: "REFLECTANCE",            
      }
    ],
    output: [
      {
        id: "default",
        bands: 12,
        sampleType: "UINT16",        
      },    
    ],
  };
}


function evaluatePixel(sample) {
    let val = [10000 * sample.B01, 10000 * sample.B02, 10000 * sample.B03, 10000 * sample.B04, 10000 * sample.B05, 10000 * sample.B06, 10000 * sample.B07, 10000 * sample.B08, 10000 * sample.B8A, 10000 * sample.B09, 10000 * sample.B11, 10000 * sample.B12];
    return val;
}

[rickus7.swanepoel (Rickus Swanepoel)]

Thanks William, that has solved the problem, appreciate the help.