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Anisotropic
Directionally dependent
crs
Coordinate Reference System. A coordinate system, as defined by a relevant authority
such as EPSG or
SR-ORG, specified as a string with the
authority and the code separated by a colon, for example 'EPSG:4326'.
crs_transform
A post transform for a crs, defined as a
list of affine transformation parameters in row-major order [xScale, xShearing,
xTranslation, yShearing, yScale, yTranslation]. See
this
reference for more information.
An image metadata property for the number of points found to be positionally consistent
with a reference image known to be accurately registered. Numbers greater than 1000
indicate a good match.
google:registration_offset_*
The measured offset, in meters, between the image and a reference image known to be
accurately registered.
The Earth Engine time stamp in milliseconds since the UNIX epoch. See
this link for more information.
The time stamp is set to the nominal image acquisition time for single scenes. It is set
to the nominal composite start period for temporal composites.
system:time_end
See system:time_start. The ending time stamp is set to the nominal image acquisition
time for single scenes. It is set to midnight on the day after the nominal composite
end period for MODIS temporal composites.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2021-12-03 UTC."],[[["\u003cp\u003eThis glossary defines common terms and acronyms (like NDVI, DEM, and MODIS) encountered in Earth Engine.\u003c/p\u003e\n"],["\u003cp\u003eIt explains technical metadata properties such as \u003ccode\u003ecrs\u003c/code\u003e, \u003ccode\u003ecrs_transform\u003c/code\u003e, and \u003ccode\u003esystem:time_start\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eIt includes links to external resources for further information on certain topics like FIRMS and SAD.\u003c/p\u003e\n"],["\u003cp\u003eThe glossary covers concepts related to image properties (isotropic, anisotropic) and data quality (registration).\u003c/p\u003e\n"]]],[],null,["# Glossary\n\n### Anisotropic\n\n: Directionally dependent\n\n### `crs`\n\n: Coordinate Reference System. A coordinate system, as defined by a relevant authority\n such as [EPSG](http://epsg.io/) or\n [SR-ORG](http://spatialreference.org/), specified as a string with the\n authority and the code separated by a colon, for example `'EPSG:4326'`.\n\n### `crs_transform`\n\n: A post transform for a `crs`, defined as a\n list of affine transformation parameters in row-major order \\[xScale, xShearing,\n xTranslation, yShearing, yScale, yTranslation\\]. See\n [this\n reference](https://docs.oracle.com/javase/8/docs/api/java/awt/geom/AffineTransform.html) for more information.\n\n### DEM\n\n: Digital Elevation Model\n\n### DN\n\n: Digital Number\n\n### DOY\n\n: Day Of Year\n\n### FIRMS\n\n: [Fire\n Information for Resource Management System](https://earthdata.nasa.gov/earth-observation-data/near-real-time/firms)\n\n### google:registration_count\n\n: An image metadata property for the number of points found to be positionally consistent\n with a reference image known to be accurately registered. Numbers greater than 1000\n indicate a good match.\n\n### google:registration_offset_\\*\n\n: The measured offset, in meters, between the image and a reference image known to be\n accurately registered.\n\n### Isotropic\n\n: Independent of direction\n\n### MODIS\n\n: [MODerate resolution Imaging Spectro-radiometer](http://modis.gsfc.nasa.gov/)\n\n### NIR\n\n: Near Infra-Red\n\n### NDVI\n\n: Normalized Difference Vegetation Index. (NIR - red) / (NIR + red)\n\n### NDWI\n\n: Normalized Difference Water Index. (green - NIR) / (green + NIR)\n\n### SAD\n\n: [Sistema\n de Alerta de Desmatamento](http://imazon.org.br/imprensa/sistema-de-alerta-de-desmatamento-sad-operacional-na-plataforma-google-earth-engine/)\n\n### SD\n\n: Standard Deviation\n\n### `system:time_start`\n\n: The Earth Engine time stamp in milliseconds since the UNIX epoch. See\n [this link](https://en.wikipedia.org/wiki/Unix_time) for more information.\n The time stamp is set to the nominal image acquisition time for single scenes. It is set\n to the nominal composite start period for temporal composites.\n\n### `system:time_end`\n\n: See system:time_start. The ending time stamp is set to the nominal image acquisition\n time for single scenes. It is set to midnight on the day after the nominal composite\n end period for MODIS temporal composites.\n\n### USGS\n\n: [United States Geological Survey](http://www.usgs.gov/)\n\n### WRI\n\n: [World Resources Institute](http://www.wri.org/)"]]