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2025년 4월 15일 전에 Earth Engine 사용을 위해 등록된 모든 비상업용 프로젝트는 Earth Engine 액세스를 유지하기 위해
비상업용 자격 요건을 인증해야 합니다.
ee.Image.reduceRegion
컬렉션을 사용해 정리하기
내 환경설정을 기준으로 콘텐츠를 저장하고 분류하세요.
특정 영역의 모든 픽셀에 리듀서를 적용합니다.
리듀서의 입력 개수는 입력 이미지의 밴드 수와 같아야 합니다. 그렇지 않으면 입력이 하나여야 하며 각 밴드에 대해 반복됩니다.
리듀서의 출력 사전이 반환됩니다.
사용 | 반환 값 |
---|
Image.reduceRegion(reducer, geometry, scale, crs, crsTransform, bestEffort, maxPixels, tileScale) | 딕셔너리 |
인수 | 유형 | 세부정보 |
---|
다음과 같은 경우: image | 이미지 | 축소할 이미지입니다. |
reducer | 감소기 | 적용할 리듀서입니다. |
geometry | 기하학, 기본값: null | 데이터를 축소할 리전입니다. 기본값은 이미지의 첫 번째 밴드의 설치 공간입니다. |
scale | 부동 소수점 수, 기본값: null | 작업할 투영의 명목상 척도(미터)입니다. |
crs | 예상, 기본값: null | 작업할 투영입니다. 지정하지 않으면 이미지의 첫 번째 밴드의 투영이 사용됩니다. 크기 조정 외에 지정된 경우 지정된 크기로 다시 조정됩니다. |
crsTransform | 목록, 기본값: null | CRS 변환 값 목록입니다. 이는 3x2 변환 행렬의 행 우선 순서입니다. 이 옵션은 'scale'과 상호 배타적이며 프로젝션에 이미 설정된 변환을 대체합니다. |
bestEffort | 불리언, 기본값: false | 다각형에 지정된 스케일에서 너무 많은 픽셀이 포함되는 경우 작업이 성공할 수 있도록 더 큰 스케일을 계산하여 사용합니다. |
maxPixels | long, 기본값: 10000000 | 줄일 최대 픽셀 수입니다. |
tileScale | 부동 소수점 수, 기본값: 1 | 집계 타일 크기를 조정하는 데 사용되는 0.1~16 사이의 확장 요소입니다. tileScale을 더 크게 설정하면 (예: 2 또는 4)는 더 작은 타일을 사용하며 기본값으로 메모리가 부족한 계산을 사용 설정할 수 있습니다. |
예
코드 편집기 (JavaScript)
// A Landsat 8 surface reflectance image with SWIR1, NIR, and green bands.
var img = ee.Image('LANDSAT/LC08/C02/T1_L2/LC08_044034_20210508')
.select(['SR_B6', 'SR_B5', 'SR_B3']);
// Santa Cruz Mountains ecoregion geometry.
var geom = ee.FeatureCollection('EPA/Ecoregions/2013/L4')
.filter('us_l4name == "Santa Cruz Mountains"').geometry();
// Display layers on the map.
Map.setCenter(-122.08, 37.22, 9);
Map.addLayer(img, {min: 10000, max: 20000}, 'Landsat image');
Map.addLayer(geom, {color: 'white'}, 'Santa Cruz Mountains ecoregion');
// Calculate median band values within Santa Cruz Mountains ecoregion. It is
// good practice to explicitly define "scale" (or "crsTransform") and "crs"
// parameters of the analysis to avoid unexpected results from undesired
// defaults when e.g. reducing a composite image.
var stats = img.reduceRegion({
reducer: ee.Reducer.median(),
geometry: geom,
scale: 30, // meters
crs: 'EPSG:3310', // California Albers projection
});
// A dictionary is returned; keys are band names, values are the statistic.
print('Median band values, Santa Cruz Mountains ecoregion', stats);
// You can combine reducers to calculate e.g. mean and standard deviation
// simultaneously. The output dictionary keys are the concatenation of the band
// names and statistic names, separated by an underscore.
var reducer = ee.Reducer.mean().combine({
reducer2: ee.Reducer.stdDev(),
sharedInputs: true
});
var multiStats = img.reduceRegion({
reducer: reducer,
geometry: geom,
scale: 30,
crs: 'EPSG:3310',
});
print('Mean & SD band values, Santa Cruz Mountains ecoregion', multiStats);
Python 설정
Python API 및 geemap
를 사용한 대화형 개발에 관한 자세한 내용은
Python 환경 페이지를 참고하세요.
import ee
import geemap.core as geemap
Colab (Python)
# A Landsat 8 surface reflectance image with SWIR1, NIR, and green bands.
img = ee.Image('LANDSAT/LC08/C02/T1_L2/LC08_044034_20210508').select(
['SR_B6', 'SR_B5', 'SR_B3']
)
# Santa Cruz Mountains ecoregion geometry.
geom = (
ee.FeatureCollection('EPA/Ecoregions/2013/L4')
.filter('us_l4name == "Santa Cruz Mountains"')
.geometry()
)
# Display layers on the map.
m = geemap.Map()
m.set_center(-122.08, 37.22, 9)
m.add_layer(img, {'min': 10000, 'max': 20000}, 'Landsat image')
m.add_layer(geom, {'color': 'white'}, 'Santa Cruz Mountains ecoregion')
display(m)
# Calculate median band values within Santa Cruz Mountains ecoregion. It is
# good practice to explicitly define "scale" (or "crsTransform") and "crs"
# parameters of the analysis to avoid unexpected results from undesired
# defaults when e.g. reducing a composite image.
stats = img.reduceRegion(
reducer=ee.Reducer.median(),
geometry=geom,
scale=30, # meters
crs='EPSG:3310', # California Albers projection
)
# A dictionary is returned keys are band names, values are the statistic.
display('Median band values, Santa Cruz Mountains ecoregion', stats)
# You can combine reducers to calculate e.g. mean and standard deviation
# simultaneously. The output dictionary keys are the concatenation of the band
# names and statistic names, separated by an underscore.
reducer = ee.Reducer.mean().combine(
reducer2=ee.Reducer.stdDev(), sharedInputs=True
)
multi_stats = img.reduceRegion(
reducer=reducer,
geometry=geom,
scale=30,
crs='EPSG:3310',
)
display('Mean & SD band values, Santa Cruz Mountains ecoregion', multi_stats)
달리 명시되지 않는 한 이 페이지의 콘텐츠에는 Creative Commons Attribution 4.0 라이선스에 따라 라이선스가 부여되며, 코드 샘플에는 Apache 2.0 라이선스에 따라 라이선스가 부여됩니다. 자세한 내용은 Google Developers 사이트 정책을 참조하세요. 자바는 Oracle 및/또는 Oracle 계열사의 등록 상표입니다.
최종 업데이트: 2025-07-26(UTC)
[null,null,["최종 업데이트: 2025-07-26(UTC)"],[[["\u003cp\u003e\u003ccode\u003eImage.reduceRegion()\u003c/code\u003e applies a reducer function to all pixels within a specified region of an image.\u003c/p\u003e\n"],["\u003cp\u003eThe reducer can either accept the same number of inputs as the image bands or a single input to be applied to each band.\u003c/p\u003e\n"],["\u003cp\u003eIt returns a dictionary containing the reducer's output, with keys representing band names and values corresponding to the calculated statistic.\u003c/p\u003e\n"],["\u003cp\u003eUsers can define parameters like scale, projection, and geometry to control the region and resolution of the reduction operation.\u003c/p\u003e\n"],["\u003cp\u003eMultiple reducers can be combined to calculate multiple statistics simultaneously, with output dictionary keys reflecting both band and statistic names.\u003c/p\u003e\n"]]],[],null,["# ee.Image.reduceRegion\n\nApply a reducer to all the pixels in a specific region.\n\n\u003cbr /\u003e\n\nEither the reducer must have the same number of inputs as the input image has bands, or it must have a single input and will be repeated for each band.\n\nReturns a dictionary of the reducer's outputs.\n\n| Usage | Returns |\n|---------------------------------------------------------------------------------------------------------------------------------------|------------|\n| Image.reduceRegion`(reducer, `*geometry* `, `*scale* `, `*crs* `, `*crsTransform* `, `*bestEffort* `, `*maxPixels* `, `*tileScale*`)` | Dictionary |\n\n| Argument | Type | Details |\n|----------------|---------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `image` | Image | The image to reduce. |\n| `reducer` | Reducer | The reducer to apply. |\n| `geometry` | Geometry, default: null | The region over which to reduce data. Defaults to the footprint of the image's first band. |\n| `scale` | Float, default: null | A nominal scale in meters of the projection to work in. |\n| `crs` | Projection, default: null | The projection to work in. If unspecified, the projection of the image's first band is used. If specified in addition to scale, rescaled to the specified scale. |\n| `crsTransform` | List, default: null | The list of CRS transform values. This is a row-major ordering of the 3x2 transform matrix. This option is mutually exclusive with 'scale', and replaces any transform already set on the projection. |\n| `bestEffort` | Boolean, default: false | If the polygon would contain too many pixels at the given scale, compute and use a larger scale which would allow the operation to succeed. |\n| `maxPixels` | Long, default: 10000000 | The maximum number of pixels to reduce. |\n| `tileScale` | Float, default: 1 | A scaling factor between 0.1 and 16 used to adjust aggregation tile size; setting a larger tileScale (e.g., 2 or 4) uses smaller tiles and may enable computations that run out of memory with the default. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// A Landsat 8 surface reflectance image with SWIR1, NIR, and green bands.\nvar img = ee.Image('LANDSAT/LC08/C02/T1_L2/LC08_044034_20210508')\n .select(['SR_B6', 'SR_B5', 'SR_B3']);\n\n// Santa Cruz Mountains ecoregion geometry.\nvar geom = ee.FeatureCollection('EPA/Ecoregions/2013/L4')\n .filter('us_l4name == \"Santa Cruz Mountains\"').geometry();\n\n// Display layers on the map.\nMap.setCenter(-122.08, 37.22, 9);\nMap.addLayer(img, {min: 10000, max: 20000}, 'Landsat image');\nMap.addLayer(geom, {color: 'white'}, 'Santa Cruz Mountains ecoregion');\n\n// Calculate median band values within Santa Cruz Mountains ecoregion. It is\n// good practice to explicitly define \"scale\" (or \"crsTransform\") and \"crs\"\n// parameters of the analysis to avoid unexpected results from undesired\n// defaults when e.g. reducing a composite image.\nvar stats = img.reduceRegion({\n reducer: ee.Reducer.median(),\n geometry: geom,\n scale: 30, // meters\n crs: 'EPSG:3310', // California Albers projection\n});\n\n// A dictionary is returned; keys are band names, values are the statistic.\nprint('Median band values, Santa Cruz Mountains ecoregion', stats);\n\n// You can combine reducers to calculate e.g. mean and standard deviation\n// simultaneously. The output dictionary keys are the concatenation of the band\n// names and statistic names, separated by an underscore.\nvar reducer = ee.Reducer.mean().combine({\n reducer2: ee.Reducer.stdDev(),\n sharedInputs: true\n});\nvar multiStats = img.reduceRegion({\n reducer: reducer,\n geometry: geom,\n scale: 30,\n crs: 'EPSG:3310',\n});\nprint('Mean & SD band values, Santa Cruz Mountains ecoregion', multiStats);\n```\nPython setup\n\nSee the [Python Environment](/earth-engine/guides/python_install) page for information on the Python API and using\n`geemap` for interactive development. \n\n```python\nimport ee\nimport geemap.core as geemap\n```\n\n### Colab (Python)\n\n```python\n# A Landsat 8 surface reflectance image with SWIR1, NIR, and green bands.\nimg = ee.Image('LANDSAT/LC08/C02/T1_L2/LC08_044034_20210508').select(\n ['SR_B6', 'SR_B5', 'SR_B3']\n)\n\n# Santa Cruz Mountains ecoregion geometry.\ngeom = (\n ee.FeatureCollection('EPA/Ecoregions/2013/L4')\n .filter('us_l4name == \"Santa Cruz Mountains\"')\n .geometry()\n)\n\n# Display layers on the map.\nm = geemap.Map()\nm.set_center(-122.08, 37.22, 9)\nm.add_layer(img, {'min': 10000, 'max': 20000}, 'Landsat image')\nm.add_layer(geom, {'color': 'white'}, 'Santa Cruz Mountains ecoregion')\ndisplay(m)\n\n# Calculate median band values within Santa Cruz Mountains ecoregion. It is\n# good practice to explicitly define \"scale\" (or \"crsTransform\") and \"crs\"\n# parameters of the analysis to avoid unexpected results from undesired\n# defaults when e.g. reducing a composite image.\nstats = img.reduceRegion(\n reducer=ee.Reducer.median(),\n geometry=geom,\n scale=30, # meters\n crs='EPSG:3310', # California Albers projection\n)\n\n# A dictionary is returned keys are band names, values are the statistic.\ndisplay('Median band values, Santa Cruz Mountains ecoregion', stats)\n\n# You can combine reducers to calculate e.g. mean and standard deviation\n# simultaneously. The output dictionary keys are the concatenation of the band\n# names and statistic names, separated by an underscore.\nreducer = ee.Reducer.mean().combine(\n reducer2=ee.Reducer.stdDev(), sharedInputs=True\n)\nmulti_stats = img.reduceRegion(\n reducer=reducer,\n geometry=geom,\n scale=30,\n crs='EPSG:3310',\n)\ndisplay('Mean & SD band values, Santa Cruz Mountains ecoregion', multi_stats)\n```"]]