ee.ImageCollection.reduceToImage

通过对与每个像素相交的所有要素的所选属性应用归约函数,从要素集合创建图像。

用法返回
ImageCollection.reduceToImage(properties, reducer)图片
参数类型详细信息
此:collectionFeatureCollection要与每个输出像素相交的要素集合。
properties列表要从每个特征中选择并传递到 reducer 中的属性。
reducer缩减器一种用于将每个相交要素的属性合并到最终结果中以存储在像素中的 Reducer。

示例

代码编辑器 (JavaScript)

var col = ee.ImageCollection('LANDSAT/LC08/C02/T1_TOA')
  .filterBounds(ee.Geometry.BBox(-124.0, 43.2, -116.5, 46.3))
  .filterDate('2021', '2022');

// Image visualization settings.
var visParams = {
  bands: ['B4', 'B3', 'B2'],
  min: 0.01,
  max: 0.25
};
Map.addLayer(col.mean(), visParams, 'RGB mean');

// Reduce the geometry (footprint) of images in the collection to an image.
// Image property values are applied to the pixels intersecting each
// image's geometry and then a per-pixel reduction is performed according
// to the selected reducer. Here, the image cloud cover property is assigned
// to the pixels intersecting image geometry and then reduced to a single
// image representing the per-pixel mean image cloud cover.
var meanCloudCover = col.reduceToImage({
  properties: ['CLOUD_COVER'],
  reducer: ee.Reducer.mean()
});

Map.setCenter(-119.87, 44.76, 6);
Map.addLayer(meanCloudCover, {min: 0, max: 50}, 'Cloud cover mean');

Python 设置

如需了解 Python API 和如何使用 geemap 进行交互式开发,请参阅 Python 环境页面。

import ee
import geemap.core as geemap

Colab (Python)

col = (
    ee.ImageCollection('LANDSAT/LC08/C02/T1_TOA')
    .filterBounds(ee.Geometry.BBox(-124.0, 43.2, -116.5, 46.3))
    .filterDate('2021', '2022')
)

# Image visualization settings.
vis_params = {'bands': ['B4', 'B3', 'B2'], 'min': 0.01, 'max': 0.25}
m = geemap.Map()
m.add_layer(col.mean(), vis_params, 'RGB mean')

# Reduce the geometry (footprint) of images in the collection to an image.
# Image property values are applied to the pixels intersecting each
# image's geometry and then a per-pixel reduction is performed according
# to the selected reducer. Here, the image cloud cover property is assigned
# to the pixels intersecting image geometry and then reduced to a single
# image representing the per-pixel mean image cloud cover.
mean_cloud_cover = col.reduceToImage(
    properties=['CLOUD_COVER'], reducer=ee.Reducer.mean()
)

m.set_center(-119.87, 44.76, 6)
m.add_layer(mean_cloud_cover, {'min': 0, 'max': 50}, 'Cloud cover mean')
m