Preview of an Image Collection Using a Time Series Animation.

Images composing an ImageCollection can be visualized as either an animation or a series of thumbnails referred to as a filmstrip. These methods provide a quick assessment of the contents of an ImageCollection and an effective medium for detecting spatiotemporal change.

This article focuses on how to prepare an Image Collection for visualization, provide example code for collection visualization method, and time series animation techniques.

Select an area of Interest.

Select an area of interest using the geometry tool.

Select an Image collection.

Choose the dataset to be used. In this case, NDVI collection from MODIS dataset will be visualized using an animated GIF. Proceed to perform a filter for the dates, to obtain the date the image was acquired.

var collection = ee.ImageCollection("MODIS/006/MOD13Q1")
  .filterDate('2018-01-01', '2019-01-01')
  .select('NDVI');
Clip the first image to the area of interest and add it to the map.

The first image in the image collection is added to the map just as a preview.

var im = ee.Image(collection.first().clip(geometry));
Map.addLayer(im, {}, "first image"); 
Visualization.

Apply visualization parameters to the animation.

var args = {
  crs: 'EPSG:3857',  // Maps Mercator
  dimensions: '300',
  region: geometry,
  min: -2000,
  max: 10000,
  palette: 'black, blanchedalmond, green, green',
  framesPerSecond: 12,
};
Create a video thumbnail and add it to the map.
var thumb = ui.Thumbnail({
  image: collection,
  params: args,
  style: {
    position: 'bottom-right',
    width: '320px'
  }});
Display the final results.
print(collection.getVideoThumbURL(args));
Map.addLayer(geometry);
Map.centerObject(geometry, 3);
Map.add(thumb);
NDVI Animation

Link to the animation

https://earthengine.googleapis.com/v1alpha/projects/earthengine-legacy/videoThumbnails/531240e2f3217100dfd9dd09283fdfba-3c8a348c5e7a6f0b4fdea728a5370709:getPixels

Link to the full code

https://code.earthengine.google.com/f2505b99b5ae5a9b32f8e4b78b326819

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