{"id":"3dep-lidar-hag","type":"Collection","links":[{"rel":"items","type":"application/geo+json","href":"https://planetarycomputer.microsoft.com/api/stac/v1/collections/3dep-lidar-hag/items"},{"rel":"parent","type":"application/json","href":"https://planetarycomputer.microsoft.com/api/stac/v1/"},{"rel":"root","type":"application/json","href":"https://planetarycomputer.microsoft.com/api/stac/v1/"},{"rel":"self","type":"application/json","href":"https://planetarycomputer.microsoft.com/api/stac/v1/collections/3dep-lidar-hag"},{"rel":"license","href":"https://www.usgs.gov/3d-elevation-program/about-3dep-products-services","title":"About 3DEP Products & Services"},{"rel":"http://www.opengis.net/def/rel/ogc/1.0/queryables","type":"application/schema+json","title":"Queryables","href":"https://planetarycomputer.microsoft.com/api/stac/v1/collections/3dep-lidar-hag/queryables"},{"rel":"describedby","href":"https://planetarycomputer.microsoft.com/dataset/3dep-lidar-hag","title":"Human readable dataset overview and reference","type":"text/html"}],"title":"USGS 3DEP Lidar Height above Ground","assets":{"thumbnail":{"href":"https://ai4edatasetspublicassets.blob.core.windows.net/assets/pc_thumbnails/hag-thumbnail.png","type":"image/png","roles":["thumbnail"],"title":"3DEP Lidar COG"},"geoparquet-items":{"href":"abfs://items/3dep-lidar-hag.parquet","type":"application/x-parquet","roles":["stac-items"],"title":"GeoParquet STAC items","description":"Snapshot of the collection's STAC items exported to GeoParquet format.","msft:partition_info":{"is_partitioned":true,"partition_frequency":"AS"},"table:storage_options":{"account_name":"pcstacitems"}}},"extent":{"spatial":{"bbox":[[-166.8546920006028,17.655357747708283,-64.56116757979399,71.39330810146807],[144.60180842809473,13.21774453924126,146.08202179248926,18.18369664008955]]},"temporal":{"interval":[["2012-01-01T00:00:00Z","2022-01-01T00:00:00Z"]]}},"license":"proprietary","keywords":["USGS","3DEP","COG","Elevation"],"providers":[{"name":"Landrush","roles":["processor","producer"]},{"url":"https://www.usgs.gov/core-science-systems/ngp/3dep/","name":"USGS","roles":["processor","producer","licensor"]},{"url":"https://planetarycomputer.microsoft.com","name":"Microsoft","roles":["host","processor"]}],"summaries":{"gsd":[2.0]},"description":"This COG type is generated using the Z dimension of the [COPC data](https://planetarycomputer.microsoft.com/dataset/3dep-lidar-copc) data and removes noise, water, and using [`pdal.filters.smrf`](https://pdal.io/stages/filters.smrf.html#filters-smrf) followed by [pdal.filters.hag_nn](https://pdal.io/stages/filters.hag_nn.html#filters-hag-nn).\n\nThe Height Above Ground Nearest Neighbor filter takes as input a point cloud with Classification set to 2 for ground points. It creates a new dimension, HeightAboveGround, that contains the normalized height values.\n\nGround points may be generated with [`pdal.filters.pmf`](https://pdal.io/stages/filters.pmf.html#filters-pmf) or [`pdal.filters.smrf`](https://pdal.io/stages/filters.smrf.html#filters-smrf), but you can use any method you choose, as long as the ground returns are marked.\n\nNormalized heights are a commonly used attribute of point cloud data. This can also be referred to as height above ground (HAG) or above ground level (AGL) heights. In the end, it is simply a measure of a point's relative height as opposed to its raw elevation value.\n\nThe filter finds the number of ground points nearest to the non-ground point under consideration. It calculates an average ground height weighted by the distance of each ground point from the non-ground point. The HeightAboveGround is the difference between the Z value of the non-ground point and the interpolated ground height.\n","item_assets":{"data":{"type":"image/tiff; application=geotiff; profile=cloud-optimized","roles":["data"],"title":"COG data","raster:bands":[{"name":"HeightAboveGround","unit":"metre","sampling":"point","data_type":"float32","description":"Raster for Height Above Ground (HAG)"}]},"thumbnail":{"type":"image/png","roles":["thumbnail"],"title":"3DEP Lidar COG"}},"stac_version":"1.0.0","msft:group_id":"3dep-lidar","msft:container":"usgs-3dep-cogs","stac_extensions":["https://stac-extensions.github.io/item-assets/v1.0.0/schema.json","https://stac-extensions.github.io/raster/v1.1.0/schema.json#","https://stac-extensions.github.io/table/v1.2.0/schema.json"],"msft:storage_account":"usgslidareuwest","msft:short_description":"3DEP Lidar collection for the Height Above Ground (HAG or Elevation) Cloud Optimized Geotiffs (COGs). All USGS HAG COG STAC items will be associated with this STAC collection.","msft:region":"westeurope"}