公告:所有在
2025 年 4 月 15 日之前注册使用 Earth Engine 的非商业项目都必须
验证是否符合非商业性质的资格条件,才能继续使用 Earth Engine。
ee.Image.updateMask
使用集合让一切井井有条
根据您的偏好保存内容并对其进行分类。
更新现有遮罩不为零的所有位置的图片遮罩。输出图片会保留输入图片的元数据和覆盖区。
用法 | 返回 |
---|
Image.updateMask(mask) | 图片 |
参数 | 类型 | 详细信息 |
---|
此:image | 图片 | 输入图片。 |
mask | 图片 | 图片的新遮罩,以介于 [0, 1] 范围内的浮点值表示(无效 = 0,有效 = 1)。如果此图片具有单个波段,则用于输入图片中的所有波段;否则,必须具有与输入图片相同的波段数。 |
示例
代码编辑器 (JavaScript)
// A Sentinel-2 surface reflectance image.
var img = ee.Image('COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG');
var trueColorViz = {
bands: ['B4', 'B3', 'B2'],
min: 0,
max: 2700,
gamma: 1.3
};
print('Sentinel-2 image', img);
Map.setCenter(-122.36, 37.47, 10);
Map.addLayer(img, trueColorViz, 'Sentinel-2 image');
// Create a Boolean land mask from the SWIR1 band; water is value 0, land is 1.
var landMask = img.select('B11').gt(100);
print('Land mask', landMask);
Map.addLayer(landMask, {palette: ['blue', 'lightgreen']}, 'Land mask');
// Apply the single-band land mask to all image bands; pixel values equal to 0
// in the mask become invalid in the image.
var imgMasked = img.updateMask(landMask);
print('Image, land only', imgMasked);
Map.addLayer(imgMasked, trueColorViz, 'Image, land only');
// Masks are band-specific. Here, a multi-band mask image is used to update
// corresponding input image band masks.
var imgBandSubset = img.select(['B4', 'B3', 'B2']);
var bandSpecificMasks = imgBandSubset.gt(200);
var imgBandSubsetMasked = imgBandSubset.updateMask(bandSpecificMasks);
print('Multi-band mask image', bandSpecificMasks);
print('Image, variable band masks', imgBandSubsetMasked);
Map.addLayer(bandSpecificMasks, null, 'Multi-band mask image');
Map.addLayer(imgBandSubsetMasked, trueColorViz, 'Image, variable band masks');
// Note that there is only a single alpha channel for visualization, so when
// the ee.Image is rendered as an RGB image or map tiles, a masked pixel in any
// band will result in transparency for all bands.
// Floating point mask values between 0 and 1 will be used to define opacity
// in visualization via Map.addLayer and ee.Image.visualize.
var landMaskFloat = landMask.add(0.65);
var imgMaskedFloat = img.updateMask(landMaskFloat);
print('Image, partially transparent', imgMaskedFloat);
Map.addLayer(imgMaskedFloat, trueColorViz, 'Image, partially transparent');
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)
# A Sentinel-2 surface reflectance image.
img = ee.Image('COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG')
true_color_viz = {
'bands': ['B4', 'B3', 'B2'],
'min': 0,
'max': 2700,
'gamma': 1.3,
}
display('Sentinel-2 image', img)
m = geemap.Map()
m.set_center(-122.36, 37.47, 10)
m.add_layer(img, true_color_viz, 'Sentinel-2 image')
# Create a Boolean land mask from the SWIR1 band water is value 0, land is 1.
land_mask = img.select('B11').gt(100)
display('Land mask', land_mask)
m.add_layer(land_mask, {'palette': ['blue', 'lightgreen']}, 'Land mask')
# Apply the single-band land mask to all image bands pixel values equal to 0
# in the mask become invalid in the image.
img_masked = img.updateMask(land_mask)
display('Image, land only', img_masked)
m.add_layer(img_masked, true_color_viz, 'Image, land only')
# Masks are band-specific. Here, a multi-band mask image is used to update
# corresponding input image band masks.
img_band_subset = img.select(['B4', 'B3', 'B2'])
band_specific_masks = img_band_subset.gt(200)
img_band_subset_masked = img_band_subset.updateMask(band_specific_masks)
display('Multi-band mask image', band_specific_masks)
display('Image, variable band masks', img_band_subset_masked)
m.add_layer(band_specific_masks, None, 'Multi-band mask image')
m.add_layer(
img_band_subset_masked, true_color_viz, 'Image, variable band masks'
)
# Note that there is only a single alpha channel for visualization, so when
# the ee.Image is rendered as an RGB image or map tiles, a masked pixel in any
# band will result in transparency for all bands.
# Floating point mask values between 0 and 1 will be used to define opacity
# in visualization via m.add_ee_layer and ee.Image.visualize.
land_mask_float = land_mask.add(0.65)
img_masked_float = img.updateMask(land_mask_float)
display('Image, partially transparent', img_masked_float)
m.add_layer(img_masked_float, true_color_viz, 'Image, partially transparent')
m
如未另行说明,那么本页面中的内容已根据知识共享署名 4.0 许可获得了许可,并且代码示例已根据 Apache 2.0 许可获得了许可。有关详情,请参阅 Google 开发者网站政策。Java 是 Oracle 和/或其关联公司的注册商标。
最后更新时间 (UTC):2025-07-26。
[null,null,["最后更新时间 (UTC):2025-07-26。"],[[["\u003cp\u003e\u003ccode\u003eupdateMask()\u003c/code\u003e modifies an image's mask, making pixels with a mask value of 0 invalid.\u003c/p\u003e\n"],["\u003cp\u003eIt accepts a single or multi-band image as a mask, applying it to corresponding bands in the input image.\u003c/p\u003e\n"],["\u003cp\u003eThe input image's metadata and footprint are preserved in the output.\u003c/p\u003e\n"],["\u003cp\u003eFloating point mask values (0-1) control pixel opacity during visualization.\u003c/p\u003e\n"]]],["The `updateMask()` function modifies an image's existing mask. It takes a new mask as input, a floating-point image where 0 denotes invalid and 1 denotes valid pixels. When applied, the function updates all image pixels where the current mask is non-zero. The new mask can be single-band, affecting all input image bands, or multi-band, updating bands individually. Mask values between 0 and 1 indicate partial transparency. The output image keeps the input image's metadata and footprint.\n"],null,["# ee.Image.updateMask\n\nUpdates an image's mask at all positions where the existing mask is not zero. The output image retains the metadata and footprint of the input image.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|--------------------------|---------|\n| Image.updateMask`(mask)` | Image |\n\n| Argument | Type | Details |\n|---------------|-------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `image` | Image | Input image. |\n| `mask` | Image | New mask for the image, as a floating-point value in the range \\[0, 1\\] (invalid = 0, valid = 1). If this image has a single band, it is used for all bands in the input image; otherwise, must have the same number of bands as the input image. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// A Sentinel-2 surface reflectance image.\nvar img = ee.Image('COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG');\nvar trueColorViz = {\n bands: ['B4', 'B3', 'B2'],\n min: 0,\n max: 2700,\n gamma: 1.3\n};\nprint('Sentinel-2 image', img);\nMap.setCenter(-122.36, 37.47, 10);\nMap.addLayer(img, trueColorViz, 'Sentinel-2 image');\n\n// Create a Boolean land mask from the SWIR1 band; water is value 0, land is 1.\nvar landMask = img.select('B11').gt(100);\nprint('Land mask', landMask);\nMap.addLayer(landMask, {palette: ['blue', 'lightgreen']}, 'Land mask');\n\n// Apply the single-band land mask to all image bands; pixel values equal to 0\n// in the mask become invalid in the image.\nvar imgMasked = img.updateMask(landMask);\nprint('Image, land only', imgMasked);\nMap.addLayer(imgMasked, trueColorViz, 'Image, land only');\n\n// Masks are band-specific. Here, a multi-band mask image is used to update\n// corresponding input image band masks.\nvar imgBandSubset = img.select(['B4', 'B3', 'B2']);\nvar bandSpecificMasks = imgBandSubset.gt(200);\nvar imgBandSubsetMasked = imgBandSubset.updateMask(bandSpecificMasks);\nprint('Multi-band mask image', bandSpecificMasks);\nprint('Image, variable band masks', imgBandSubsetMasked);\nMap.addLayer(bandSpecificMasks, null, 'Multi-band mask image');\nMap.addLayer(imgBandSubsetMasked, trueColorViz, 'Image, variable band masks');\n// Note that there is only a single alpha channel for visualization, so when\n// the ee.Image is rendered as an RGB image or map tiles, a masked pixel in any\n// band will result in transparency for all bands.\n\n// Floating point mask values between 0 and 1 will be used to define opacity\n// in visualization via Map.addLayer and ee.Image.visualize.\nvar landMaskFloat = landMask.add(0.65);\nvar imgMaskedFloat = img.updateMask(landMaskFloat);\nprint('Image, partially transparent', imgMaskedFloat);\nMap.addLayer(imgMaskedFloat, trueColorViz, 'Image, partially transparent');\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 Sentinel-2 surface reflectance image.\nimg = ee.Image('COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG')\ntrue_color_viz = {\n 'bands': ['B4', 'B3', 'B2'],\n 'min': 0,\n 'max': 2700,\n 'gamma': 1.3,\n}\ndisplay('Sentinel-2 image', img)\nm = geemap.Map()\nm.set_center(-122.36, 37.47, 10)\nm.add_layer(img, true_color_viz, 'Sentinel-2 image')\n\n# Create a Boolean land mask from the SWIR1 band water is value 0, land is 1.\nland_mask = img.select('B11').gt(100)\ndisplay('Land mask', land_mask)\nm.add_layer(land_mask, {'palette': ['blue', 'lightgreen']}, 'Land mask')\n\n# Apply the single-band land mask to all image bands pixel values equal to 0\n# in the mask become invalid in the image.\nimg_masked = img.updateMask(land_mask)\ndisplay('Image, land only', img_masked)\nm.add_layer(img_masked, true_color_viz, 'Image, land only')\n\n# Masks are band-specific. Here, a multi-band mask image is used to update\n# corresponding input image band masks.\nimg_band_subset = img.select(['B4', 'B3', 'B2'])\nband_specific_masks = img_band_subset.gt(200)\nimg_band_subset_masked = img_band_subset.updateMask(band_specific_masks)\ndisplay('Multi-band mask image', band_specific_masks)\ndisplay('Image, variable band masks', img_band_subset_masked)\nm.add_layer(band_specific_masks, None, 'Multi-band mask image')\nm.add_layer(\n img_band_subset_masked, true_color_viz, 'Image, variable band masks'\n)\n# Note that there is only a single alpha channel for visualization, so when\n# the ee.Image is rendered as an RGB image or map tiles, a masked pixel in any\n# band will result in transparency for all bands.\n\n# Floating point mask values between 0 and 1 will be used to define opacity\n# in visualization via m.add_ee_layer and ee.Image.visualize.\nland_mask_float = land_mask.add(0.65)\nimg_masked_float = img.updateMask(land_mask_float)\ndisplay('Image, partially transparent', img_masked_float)\nm.add_layer(img_masked_float, true_color_viz, 'Image, partially transparent')\nm\n```"]]