画像情報とメタデータ

Google Colab で実行

GitHub でソースを見る

画像オブジェクトを出力して、バンド名、投影情報、プロパティなどのメタデータを調べます。次の例は、画像メタデータのセット全体を出力する方法と、特定のメタデータ要素をプログラムでリクエストする方法を示しています。

メタデータの取得

コードエディタ（JavaScript）

// Load an image.
var image = ee.Image('LANDSAT/LC08/C02/T1/LC08_044034_20140318');

// Display all metadata.
print('All metadata:', image);

// Get information about the bands as a list.
var bandNames = image.bandNames();
print('Band names:', bandNames);  // ee.List of band names

// Get projection information from band 1.
var b1proj = image.select('B1').projection();
print('Band 1 projection:', b1proj);  // ee.Projection object

// Get scale (in meters) information from band 1.
var b1scale = image.select('B1').projection().nominalScale();
print('Band 1 scale:', b1scale);  // ee.Number

// Note that different bands can have different projections and scale.
var b8scale = image.select('B8').projection().nominalScale();
print('Band 8 scale:', b8scale);  // ee.Number

// Get a list of all metadata properties.
var properties = image.propertyNames();
print('Metadata properties:', properties);  // ee.List of metadata properties

// Get a specific metadata property.
var cloudiness = image.get('CLOUD_COVER');
print('CLOUD_COVER:', cloudiness);  // ee.Number

// Get version number (ingestion timestamp as microseconds since Unix epoch).
var version = image.get('system:version');
print('Version:', version);  // ee.Number
print('Version (as ingestion date):',
      ee.Date(ee.Number(version).divide(1000)));  // ee.Date

// Get the timestamp and convert it to a date.
var date = ee.Date(image.get('system:time_start'));
print('Timestamp:', date);  // ee.Date

Python の設定

Python API とインタラクティブな開発で geemap を使用する方法については、 Python 環境のページをご覧ください。

import ee
import geemap.core as geemap

Colab（Python）

# Load an image.
image = ee.Image('LANDSAT/LC08/C02/T1/LC08_044034_20140318')

# All metadata.
display('All metadata:', image)

# Get information about the bands as a list.
band_names = image.bandNames()
display('Band names:', band_names)  # ee.List of band names

# Get projection information from band 1.
b1_proj = image.select('B1').projection()
display('Band 1 projection:', b1_proj)  # ee.Projection object

# Get scale (in meters) information from band 1.
b1_scale = image.select('B1').projection().nominalScale()
display('Band 1 scale:', b1_scale)  # ee.Number

# Note that different bands can have different projections and scale.
b8_scale = image.select('B8').projection().nominalScale()
display('Band 8 scale:', b8_scale)  # ee.Number

# Get a list of all metadata properties.
properties = image.propertyNames()
display('Metadata properties:', properties)  # ee.List of metadata properties

# Get a specific metadata property.
cloudiness = image.get('CLOUD_COVER')
display('CLOUD_COVER:', cloudiness)  # ee.Number

# Get version number (ingestion timestamp as microseconds since Unix epoch).
version = image.get('system:version')
display('Version:', version)  # ee.Number
display(
    'Version (as ingestion date):',
    ee.Date(ee.Number(version).divide(1000)).format(),
)  # ee.Date

# Get the timestamp.
ee_date = ee.Date(image.get('system:time_start'))
display('Timestamp:', ee_date)  # ee.Date

# Date objects transferred to the client are milliseconds since UNIX epoch;
# convert to human readable date with ee.Date.format().
display('Datetime:', ee_date.format())  # ISO standard date string