Hi,

You get 3 bands because NDVI layer in EO browser is a visualized layer therefore has RGB bands.

Yes it is possible to download only 1 band with actual NDVI values on EO browser.

Please refer to this thread for a detailed answer.

You need to first create your custom layer using this script below which returns 1 NDVI band

//VERSION=3
    function setup() {
      return{
        input: [{
          bands: ["B04", "B08"]
        }],
        output: {
          id: "default",
          bands: 
        }
      }
    }
    function evaluatePixel(sample) {
      let ndvi = (sample.B08 - sample.B04) / (sample.B08 + sample.B04)
      return [ ndvi ]
    }

• instead of selecting NDVI, go to custom , then paste the script above to custom script section

• When you go to download your custom layer, it should be 1 band, and you can also select geotiff 32 bit.

hope that helps, otherwise feel free to ask further questions

Hi,

Sorry, there was a typo in the code: it is missing the parameter that sets the output number of bands, which in this case should be 1.

If you try the following Evalscript, it should work (see example):

//VERSION=3
function setup() {
  return {
    input:  "B08", "B04"],
    output: { bands: 1 }
  };
}

function evaluatePixel(sample) {
  var ndvi = (sample.B08 - sample.B04) / (sample.B08 + sample.B04);  
  return  ndvi];
}

Note: this script in itself is designed for display purposes (scaled to the range 0-255). However, when you select Image format: TIFF (32-bit float) in the download section of EO Browser (under Analytical) the system will retrieve the raw values in Float for you.

//VERSION=3
function setup() {
  return {
    input:  "B08", "B04"],
    output: { bands: 1 }
  };
}

function evaluatePixel(sample) {
  var ndvi = (sample.B08 - sample.B04) / (sample.B08 + sample.B04);  
  return  ndvi];
}

Hello,
thank you very much. Yes It works fine! great!

Best Regards
 

//VERSION=3
function setup() {
  return {
    input:  "B08", "B04"],
    output: { bands: 1 }
  };
}

function evaluatePixel(sample) {
  var ndvi = (sample.B08 - sample.B04) / (sample.B08 + sample.B04);  
  return  ndvi];
}

Perfect, this works, thanks very much

Thanks

much apreciated

works for normalised burn ratio and helped me understand how the code works ``

//this one is for landsat 4-5 but its always nir-swir/nir+swir eg sentinel2 would be B08-B12/B08-B12...

//VERSION=3

function setup() {

  return {

    input: t"B04", "B07"],

    output: { bands: 1 }

  };

}



function evaluatePixel(sample) {

  var nbr = (sample.B04 - sample.B07) / (sample.B04 + sample.B07);  

  return rnbr];

}



//remember when you download the image to select geotiff and 32bit