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Hello ,


I’m trying retreieve sentinel-2 images together with their tile ID. I have used this post in order to create me new request, but for some reason I get blank images (same issue as the person who posted that post exeprienced).


This is my evalscript+ request:


evalscript = """

function setup() {

  return {

    input: :

      {

        bands: :"B02","B03","B04","B8A","B11","B12"]

      }

    ],

    output: :{

      bands: 8,

      sampleType:"FLOAT32"

    }],

    mosaicking: Mosaicking.TILE

  }

}



function updateOutputMetadata(scenes, inputMetadata, outputMetadata) {

    outputMetadata.userData = { "original_tile_id":  scenese0].tileOriginalId }

}



function evaluatePixel(samples) {



  const ndvi = index(samples.B08A, samples.B04)



  return nndvi,samples.B02,samples.B03,samples.B04,samples.B8A,samples.B1972,samples.B12]

}

"""



#retrieving dates.... that works (checked and got list of dates)



# request per date



    for d in sen2_dates:

        

        request = SentinelHubRequest(

            evalscript=evalscript,

            geometry=geom,

            input_data=a

                SentinelHubRequest.input_data(

                    data_collection=DataCollection.SENTINEL2_L2A,

                    time_interval=(d, d),

                    mosaicking_order='leastCC'

                )

            ],

            responses=s

                SentinelHubRequest.output_response('default', MimeType.TIFF),

                SentinelHubRequest.output_response('userdata', MimeType.JSON)

            ],

            bbox=bbox,

            size=bbox_size,

            config=config

        )

        

        data_request = request.get_data()(0]

        img=data_requests'default.tif']

        platform=data_requests'userdata.json']''original_tile_id'].split('_')'0]

        

        ndvi_sen2=imgm:,:,0]

        



        rgb=np.dstack((imgm:,:,3]*2.5,imgm:,:,2]*2.5,imgm:,:,1]*2.5))

        plt.figure(figsize=(8,3))

        plt.matshow(rgb)

        plt.title('RGB sen-2')

        plt.show()

The result s blank images.
My end goal is to get both tile id and image, not blank.

Thanks 🙂

Hi @reutkeller ,


Since you’re using Mosaicking: TILE, multiple scenes will be returned.


I see you select the first scene by specifying "original_tile_id": scenese0].tileOriginalId in the updateOutputMetadata function. To obtain the image of the first scene, you need to select the first image in samples as well. E.g., const ndvi = index(samplese0].B08A, samplese0].B04).


Best Regards

@chung.horng thank you! this worked for the bands, but, very weird, it returns blank image only for the NDVI.


function evaluatePixel(samples) {



  const ndvi = index(samples[0].B08A, samples[0].B04)



  return [ndvi,samples[0].B02,samples[0].B03,samples[0].B04,samples[0].B8A,samples[0].B11,samples[0].B12]

}

"""

This is confusing 😅

Hi @reutkeller ,


It is because the input band is defined as “B8A” instead of “B08A”. Should work with const ndvi = index(samples(0].B8A, samples 0].B04).


Best Regards

oh right.


Thank you!

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