Enhanced true color visualization
// Sentinel-3 data Visualization V1.0.0
// Twitter: Pierre Markuse (@pierre_markuse)
// Website: https://pierre-markuse.net/
// CC BY 4.0 International - https://creativecommons.org/licenses/by/4.0/
function stretch(val, min, max) {return (val - min) / (max - min);}
function blend(bArr1, bArr2, opa1, opa2) {
return bArr1.map(function(num, index) {
return (num / 100 * opa1 + bArr2[index] / 100 * opa2);
});
}
var NaturalColors1 = [1.0 * B07 + 1.4 * B09 - 0.1 * B14, 1.1 * B05 + 1.4 * B06 - 0.2 * B14, (2.6 * B04 - B14 * 0.6)*1.00];
var NaturalColors2 = [1.0 * B07 + 1.4 * B09 - 0.2 * B14, 1.0 * B05 + 1.5 * B06 - 0.45 * B14, (2.6 * B04 - B14 * 1.0)*1.02];
var NaturalColors3 = [1.0 * B07 + 1.4 * B09 - 0.3 * B14, 1.0 * B05 + 1.5 * B06 - 0.6 * B14, (2.6 * B04 - B14 * 1.2)*1.03];
var NIR = [2.0 * B14, 2.0 * B07, 2.0 * B04];
var AC = [2 * B14, 2 * B14, 2 * B14];
var layer1 = NaturalColors1; // Visualization layer 1
var layer2 = NIR; // Visualization layer 2
var layer1Amount = 100; // Amount layer 1
var layer2Amount = 0; // Amount layer 2
var stretchMin = 0.15; //Change black point
var stretchMax = 0.80; //Change white point
var saturation = 0.00; //Change saturation in percent
var brightness = 1.50; //Brightness, default=1.5
var manualCorrection = [0.00, 0.00,0.00]; //Manual correction of RGB values
var visualization = blend(layer1, layer2, layer1Amount, layer2Amount);
var result = [visualization[0] * brightness, visualization[1] * brightness, visualization[2] * brightness];
result = [stretch(result[0],stretchMin,stretchMax)+manualCorrection[0],stretch(result[1],stretchMin,stretchMax)+manualCorrection[1],stretch(result[2],stretchMin,stretchMax)+manualCorrection[2]];
var avg = (result[0]+result[1]+result[2])/3;
saturation = saturation * (-1);
if (result[0]>avg) { result[0]=result[0]-(result[0]-avg)/100*saturation } else {result[0]=result[0]+(avg-result[0])/100*saturation};
if (result[1]>avg) { result[1]=result[1]-(result[1]-avg)/100*saturation } else {result[1]=result[1]+(avg-result[1])/100*saturation};
if (result[2]>avg) { result[2]=result[2]-(result[2]-avg)/100*saturation } else {result[2]=result[2]+(avg-result[2])/100*saturation};
return result;Evaluate and Visualize
Description
This script offers different true color visualizations, a NIR visualization, and the ability to easily add more visualizations. Variables allow you to influence the resulting image regarding, brightness, contrast, and saturation.
More info here.
Description of representative images
Mozambique floods, 25.3.2019. 
Contributors:
Pierre Markuse, Twitter: @pierre_markuse