圖像集合資訊和中繼資料

如同圖片,您可以透過多種方式取得 ImageCollection ������關資訊。集合���以直接輸出至主控台,但主控台輸出內容最多只能包��� 5000 個元素。超過 5000 張圖片的相片集合必須在列印前進行篩選。相應地,列印大型集合時速度會變慢。以下範例說明如何以程式輔助方式取得圖片集合資訊:

程式碼編輯器 (JavaScript)

// Load a Landsat 8 ImageCollection for a single path-row.
var collection = ee.ImageCollection('LANDSAT/LC08/C02/T1_TOA')
    .filter(ee.Filter.eq('WRS_PATH', 44))
    .filter(ee.Filter.eq('WRS_ROW', 34))
    .filterDate('2014-03-01', '2014-08-01');
print('Collection: ', collection);

// Get the number of images.
var count = collection.size();
print('Count: ', count);

// Get the date range of images in the collection.
var range = collection.reduceColumns(ee.Reducer.minMax(), ['system:time_start'])
print('Date range: ', ee.Date(range.get('min')), ee.Date(range.get('max')))

// Get statistics for a property of the images in the collection.
var sunStats = collection.aggregate_stats('SUN_ELEVATION');
print('Sun elevation statistics: ', sunStats);

// Sort by a cloud cover property, get the least cloudy image.
var image = ee.Image(collection.sort('CLOUD_COVER').first());
print('Least cloudy image: ', image);

// Limit the collection to the 10 most recent images.
var recent = collection.sort('system:time_start', false).limit(10);
print('Recent images: ', recent);

Python 設定

請參閱「 Python 環境」頁面,瞭解 Python API 和如何使用 geemap 進行互動式開發。

import ee
import geemap.core as geemap

Colab (Python)

# Load a Landsat 8 ImageCollection for a single path-row.
collection = (
    ee.ImageCollection('LANDSAT/LC08/C02/T1_TOA')
    .filter(ee.Filter.eq('WRS_PATH', 44))
    .filter(ee.Filter.eq('WRS_ROW', 34))
    .filterDate('2014-03-01', '2014-08-01')
)
display('Collection:', collection)

# Get the number of images.
count = collection.size()
display('Count:', count)

# Get the date range of images in the collection.
range = collection.reduceColumns(ee.Reducer.minMax(), ['system:time_start'])
display('Date range:', ee.Date(range.get('min')), ee.Date(range.get('max')))

# Get statistics for a property of the images in the collection.
sun_stats = collection.aggregate_stats('SUN_ELEVATION')
display('Sun elevation statistics:', sun_stats)

# Sort by a cloud cover property, get the least cloudy image.
image = ee.Image(collection.sort('CLOUD_COVER').first())
display('Least cloudy image:', image)

# Limit the collection to the 10 most recent images.
recent = collection.sort('system:time_start', False).limit(10)
display('Recent images:', recent)