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CCC (Canopy Chlorophyll Content)

//VERSION=3 (auto-converted from 2)
var degToRad = Math.PI / 180;

function evaluatePixelOrig(samples) {
  var sample = samples[0];
  var b03_norm = normalize(sample.B03, 0, 0.253061520471542);
  var b04_norm = normalize(sample.B04, 0, 0.290393577911328);
  var b05_norm = normalize(sample.B05, 0, 0.305398915248555);
  var b06_norm = normalize(sample.B06, 0.006637972542253, 0.608900395797889);
  var b07_norm = normalize(sample.B07, 0.013972727018939, 0.753827384322927);
  var b8a_norm = normalize(sample.B8A, 0.026690138082061, 0.782011770669178);
  var b11_norm = normalize(sample.B11, 0.016388074192258, 0.493761397883092);
  var b12_norm = normalize(sample.B12, 0, 0.493025984460231);
  var viewZen_norm = normalize(Math.cos(sample.viewZenithMean * degToRad), 0.918595400582046, 1);
  var sunZen_norm  = normalize(Math.cos(sample.sunZenithAngles * degToRad), 0.342022871159208, 0.936206429175402);
  var relAzim_norm = Math.cos((sample.sunAzimuthAngles - sample.viewAzimuthMean) * degToRad)

  var n1L = neuron1LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  var n2L = neuron2LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  var n3L = neuron3LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  var n4L = neuron4LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  var n5L = neuron5LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  
  var l2L = layer2LAI(n1L, n2L, n3L, n4L, n5L);
  
  var lai = denormalize(l2L, 0.000319182538301, 14.4675094548151);
  
  var n1C = neuron1Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  var n2C = neuron2Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  var n3C = neuron3Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  var n4C = neuron4Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  var n5C = neuron5Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm);
  
  var l2C = layer2Cab(n1C, n2C, n3C, n4C, n5C);
  
  var cab = denormalize(l2C, 0.007426692959872, 873.908222110306);
  
  var ccc = lai * cab;
  return {
    default: [ccc / 900]
  }
}

function neuron1LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	+ 4.96238030555279
	- 0.023406878966470 * b03_norm
	+ 0.921655164636366 * b04_norm
	+ 0.135576544080099 * b05_norm
	- 1.938331472397950 * b06_norm
	- 3.342495816122680 * b07_norm
	+ 0.902277648009576 * b8a_norm
	+ 0.205363538258614 * b11_norm
	- 0.040607844721716 * b12_norm
	- 0.083196409727092 * viewZen_norm
	+ 0.260029270773809 * sunZen_norm
	+ 0.284761567218845 * relAzim_norm;

  return tansig(sum);
}

function neuron2LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	+ 1.416008443981500
	- 0.132555480856684 * b03_norm
	- 0.139574837333540 * b04_norm
	- 1.014606016898920 * b05_norm
	- 1.330890038649270 * b06_norm
	+ 0.031730624503341 * b07_norm
	- 1.433583541317050 * b8a_norm
	- 0.959637898574699 * b11_norm
	+ 1.133115706551000 * b12_norm
	+ 0.216603876541632 * viewZen_norm
	+ 0.410652303762839 * sunZen_norm
	+ 0.064760155543506 * relAzim_norm;

  return tansig(sum);
}

function neuron3LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	+ 1.075897047213310
	+ 0.086015977724868 * b03_norm
	+ 0.616648776881434 * b04_norm
	+ 0.678003876446556 * b05_norm
	+ 0.141102398644968 * b06_norm
	- 0.096682206883546 * b07_norm
	- 1.128832638862200 * b8a_norm
	+ 0.302189102741375 * b11_norm
	+ 0.434494937299725 * b12_norm
	- 0.021903699490589 * viewZen_norm
	- 0.228492476802263 * sunZen_norm
	- 0.039460537589826 * relAzim_norm;

  return tansig(sum);
}

function neuron4LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	+ 1.533988264655420
	- 0.109366593670404 * b03_norm
	- 0.071046262972729 * b04_norm
	+ 0.064582411478320 * b05_norm
	+ 2.906325236823160 * b06_norm
	- 0.673873108979163 * b07_norm
	- 3.838051868280840 * b8a_norm
	+ 1.695979344531530 * b11_norm
	+ 0.046950296081713 * b12_norm
	- 0.049709652688365 * viewZen_norm
	+ 0.021829545430994 * sunZen_norm
	+ 0.057483827104091 * relAzim_norm;

  return tansig(sum);
}

function neuron5LAI(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	+ 3.024115930757230
	- 0.089939416159969 * b03_norm
	+ 0.175395483106147 * b04_norm
	- 0.081847329172620 * b05_norm
	+ 2.219895367487790 * b06_norm
	+ 1.713873975136850 * b07_norm
	+ 0.713069186099534 * b8a_norm
	+ 0.138970813499201 * b11_norm
	- 0.060771761518025 * b12_norm
	+ 0.124263341255473 * viewZen_norm
	+ 0.210086140404351 * sunZen_norm
	- 0.183878138700341 * relAzim_norm;

  return tansig(sum);
}

function layer2LAI(neuron1, neuron2, neuron3, neuron4, neuron5) {
  var sum =
	+ 1.096963107077220
	- 1.500135489728730 * neuron1
	- 0.096283269121503 * neuron2
	- 0.194935930577094 * neuron3
	- 0.352305895755591 * neuron4
	+ 0.075107415847473 * neuron5;

  return sum;
}

function neuron1Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	  4.242299670155190
	+ 0.400396555256580 * b03_norm
	+ 0.607936279259404 * b04_norm
	+ 0.137468650780226 * b05_norm
	- 2.955866573461640 * b06_norm
	- 3.186746687729570 * b07_norm
	+ 2.206800751246430 * b8a_norm
	- 0.313784336139636 * b11_norm
	+ 0.256063547510639 * b12_norm
	- 0.071613219805105 * viewZen_norm
	+ 0.510113504210111 * sunZen_norm
	+ 0.142813982138661 * relAzim_norm;

  return tansig(sum);
}

function neuron2Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	- 0.259569088225796
	- 0.250781102414872 * b03_norm
	+ 0.439086302920381 * b04_norm
	- 1.160590937522300 * b05_norm
	- 1.861935250269610 * b06_norm
	+ 0.981359868451638 * b07_norm
	+ 1.634230834254840 * b8a_norm
	- 0.872527934645577 * b11_norm
	+ 0.448240475035072 * b12_norm
	+ 0.037078083501217 * viewZen_norm
	+ 0.030044189670404 * sunZen_norm
	+ 0.005956686619403 * relAzim_norm;

  return tansig(sum);
}

function neuron3Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	+ 3.130392627338360
	+ 0.552080132568747 * b03_norm
	- 0.502919673166901 * b04_norm
	+ 6.105041924966230 * b05_norm
	- 1.294386119140800 * b06_norm
	- 1.059956388352800 * b07_norm
	- 1.394092902418820 * b8a_norm
	+ 0.324752732710706 * b11_norm
	- 1.758871822827680 * b12_norm
	- 0.036663679860328 * viewZen_norm
	- 0.183105291400739 * sunZen_norm
	- 0.038145312117381 * relAzim_norm;

  return tansig(sum);
}

function neuron4Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
    + 0.774423577181620
	+ 0.211591184882422 * b03_norm
	- 0.248788896074327 * b04_norm
	+ 0.887151598039092 * b05_norm
	+ 1.143675895571410 * b06_norm
	- 0.753968830338323 * b07_norm
	- 1.185456953076760 * b8a_norm
	+ 0.541897860471577 * b11_norm
	- 0.252685834607768 * b12_norm
	- 0.023414901078143 * viewZen_norm
	- 0.046022503549557 * sunZen_norm
	- 0.006570284080657 * relAzim_norm;

  return tansig(sum);
}

function neuron5Cab(b03_norm,b04_norm,b05_norm,b06_norm,b07_norm,b8a_norm,b11_norm,b12_norm, viewZen_norm,sunZen_norm,relAzim_norm) {
  var sum =
	+ 2.584276648534610
	+ 0.254790234231378 * b03_norm
	- 0.724968611431065 * b04_norm
	+ 0.731872806026834 * b05_norm
	+ 2.303453821021270 * b06_norm
	- 0.849907966921912 * b07_norm
	- 6.425315500537270 * b8a_norm
	+ 2.238844558459030 * b11_norm
	- 0.199937574297990 * b12_norm
	+ 0.097303331714567 * viewZen_norm
	+ 0.334528254938326 * sunZen_norm
	+ 0.113075306591838 * relAzim_norm;

  return tansig(sum);
}

function layer2Cab(neuron1, neuron2, neuron3, neuron4, neuron5) {
  var sum =
	+ 0.463426463933822
	- 0.352760040599190 * neuron1
	- 0.603407399151276 * neuron2
	+ 0.135099379384275 * neuron3
	- 1.735673123851930 * neuron4
	- 0.147546813318256 * neuron5;

  return sum;
}

function normalize(unnormalized, min, max) {
  return 2 * (unnormalized - min) / (max - min) - 1;
}
function denormalize(normalized, min, max) {
  return 0.5 * (normalized + 1) * (max - min) + min;
}
function tansig(input) {
  return 2 / (1 + Math.exp(-2 * input)) - 1; 
}

function setup() {
  return {
    input: [{
      bands: [
          "B03",
          "B04",
          "B05",
          "B06",
          "B07",
          "B8A",
          "B11",
          "B12",
          "viewZenithMean",
          "viewAzimuthMean",
          "sunZenithAngles",
          "sunAzimuthAngles"
      ]
    }],
    output: [
        {
          id: "default",
          sampleType: "AUTO",
          bands: 1
        }
    ]
  }
}

function evaluatePixel(sample, scene, metadata, customData, outputMetadata) {
  const result = evaluatePixelOrig([sample], [scene], metadata, customData, outputMetadata);
  return result[Object.keys(result)[0]];
}

Evaluate and Visualize

General description of the script

CCC (Canopy Chlorophyll Content (μg / cm ^ 2)) is calculated here as the product of the leaf area index (LAI) with the leaf cholrophyll content (Cab). Note that the LAI and Cab scripts are as implemented in SNAP but without input and output validation! Input/output values which are suspect are not reported or changed. Most values, however, do not fall under this category. Visualized as an interval from 0-900. This can be adjusted in the evaluatePixel method.

Description of representative images

Canopy chlorophyll index, Rome. Acquired on 8.10.2017. Canopy chlorophyll index