ui.Thumbnail

從 ee.Image 非同步產生的固定大小縮圖。

用量	傳回
ui.Thumbnail(image, params, onClick, style)	ui.Thumbnail

引數	類型	詳細資料
image	圖片 (選填)	要從中生成縮圖的 ee.Image。預設為空白 ee.Image。
params	物件 (選用)	如要瞭解可能的參數，請參閱 ui.Thumbnail.setParams()。預設為空物件。
onClick	函式 (選用)	點選縮圖時觸發的回呼。
style	物件 (選用)	允許的 CSS 樣式物件，以及要為這個標籤設定的值。預設為空物件。

範例

程式碼編輯器 (JavaScript)

// The goal is to create a series of thumbnail images for an elevation dataset
// with different backgrounds. The background layers and image visualization
// are previewed in the Code Editor map before creating the thumbnails.

// Define a black background.
var blackBg = ee.Image.rgb(0, 0, 0)
  .visualize({min: 0, max: 255});
Map.addLayer(blackBg, {}, 'Black background');

// Define a water / land background.
var waterLandBg = ee.Image('NOAA/NGDC/ETOPO1').select('bedrock').gt(0.0)
  .visualize({palette: ['cadetblue', 'lightgray']});
Map.addLayer(waterLandBg, {}, 'Water / land background');

// A map display of a digital elevation model (DEM).
var image = ee.Image('AU/GA/DEM_1SEC/v10/DEM-S').select('elevation')
  .visualize({
     min: -10.0,
     max: 1300.0,
     palette: [
       '3ae237', 'b5e22e', 'd6e21f', 'fff705', 'ffd611', 'ffb613', 'ff8b13',
       'ff6e08', 'ff500d', 'ff0000', 'de0101', 'c21301', '0602ff', '235cb1',
       '307ef3', '269db1', '30c8e2', '32d3ef', '3be285', '3ff38f', '86e26f'
     ],
  });
Map.addLayer(image, {}, 'Elevation');

// Set the center of the map.
var lon = 133.95;
var lat = -24.69;
Map.setCenter(lon, lat, 4);

// Set the basic parameters for the thumbnail.
// Half-width of the thumbnail in degrees in EPSG:3857.
var delta = 22;
// Width and Height of the Thumbail image.
var pixels = 256;

var areaOfInterest = ee.Geometry.Rectangle(
  [lon - delta, lat - delta, lon + delta, lat + delta], null, false);

var parameters = {
  dimensions: [pixels, pixels],
  region: areaOfInterest,
  crs: 'EPSG:3857',
  format: 'png'};

// Create a thumbnail with no background fill.
// Masked pixels will be transparent.
print(ui.Thumbnail({image: image, params: parameters}));

// Use a black background to replace masked image pixels.
var imageWithBlackBg = blackBg.blend(image);
print(ui.Thumbnail({
  image: imageWithBlackBg, params: parameters}));

// Use the water / land background to replace masked image pixels.
var imageWithWaterLandBg = waterLandBg.blend(image);
print(ui.Thumbnail({
  image: imageWithWaterLandBg, params: parameters}));