Setting up true colour with IR highlight composites on volcanoes

[martin2kelko (Martin Kelko)]

Hello everyone,

I have an inquiry to help to set up True color + IR highlights on volcano sat images. Any advice or recommendations, please?

Thanks,

Martin

[lucia.guardamino]

Hello Martin,
An easy way to do it is by using EO Browser. After selecting your area of interest, you can define a theme (e.g. Volcanoes). Then, select the data source, maximum cloud coverage and time range of your search.

After selecting the image of your interest, you will have access to different visualization options, including True Color + IR highlights. Be sure to be in the Visualize tab.

From there you can also have access to the Evalscript used for the visualization:

//VERSION=3

function setup() {

   return {

    input: ["B02", "B03", "B04", "B11", "B12", "dataMask"],

    output: { bands: 4 }

  };

}

function evaluatePixel(samples) {

  var R = samples.B04 * 2.5 + Math.max(0, samples.B12 - 0.1), 

    G = samples.B03 * 2.5 + Math.max(0, samples.B11 - 0.2), 

    B = samples.B02 * 2.5

  return [R, G, B, samples.dataMask]

}

For more information on active volcanoes from the space, feel free to check our dedicated blog post

Hope you find this information useful.

Kind regards

[martin2kelko (Martin Kelko)]

Hi Luca,

thanks for you reply!

I followed your steps on Semeru volcano in Indonesia, but there is no access to False Color + IR highlights.
Please, find the attached image below.

[martin2kelko (Martin Kelko)]

I figured it out finally:)