Export image in CSV

Question

I created a small image on Google Earth Engine and now would like to export all its bands in a csv file. With a format like

| pixel id | lat | lng | band1 | ....|  
|----------|-----|-----|-------|-----|  
|__________|_____|_____|_______|_____| 

I find in the doc that it was possible to obtain this result for a FeatureCollection but nothing for Image.

The small image that I would like to export :

//load dataset
var gfc2014 = ee.Image('UMD/hansen/global_forest_change_2015');

var tree = gfc2014.select('treecover2000');

// Export the image, specifying scale and region.
Export.image.toDrive({
  image: tree.updateMask(tree),
  description: 'foret St Genis',
  scale: 30,
  region: geometry //defined with the inspector
  fileFormat: 'CSV' //of course I need to work on this one
});

Answer 1

Yes that's easily possible by exporting a table to drive. Although this is useless for large areas/high resolution (you would better just export the image), the following should get you in the right direction:

// select a band
var bandNames = ['treecover2000']; // add more if you want

//load dataset
var geometry = /* color: #d63000 */ee.Geometry.Polygon(
    [[[-98.82986842488617, 30.51973226951964],
    [-98.83055507039398, 30.50701389220806],
    [-98.81956874226898, 30.507235738627383],
    [-98.81871043538422, 30.519806208708616]]]),
    gfc2014 = ee.Image("UMD/hansen/global_forest_change_2015");
var tree = gfc2014.select(bandNames);
Map.addLayer(tree)

// use get region to get a list of long, lat, bandvalue, date
var scale = tree.projection().nominalScale();
var list = ee.ImageCollection(tree).getRegion(geometry, scale); // Don't try to print this list

// tranform to feat collection (each feat will be a row in Excel export)
var names = ee.List(list.get(0)); // first row are the names
var listIDs = ee.List.sequence(1, list.length().subtract(1));
var feats = ee.FeatureCollection(listIDs.map(function (id) {
    var data = list.get(id);
    return ee.Feature(null, ee.Dictionary.fromLists(names, data)).set('ID', id);
}));
print(feats.limit(2));

// Export the featureCollection
Export.table.toDrive({
    collection: feats,
    description: 'foretStGenis',
    fileFormat: 'CSV',
    selectors: ['ID', 'latitude', 'longitude'].concat(bandNames)
});

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