From 07bfee49d71c3b7cf67dc4a58d78f9d5c34107b1 Mon Sep 17 00:00:00 2001 From: Matthias Mohr Date: Thu, 2 May 2024 17:25:46 +0200 Subject: [PATCH] Started SAR work --- radar.md | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 57 insertions(+), 1 deletion(-) diff --git a/radar.md b/radar.md index 0f8ec64..d76ac7c 100644 --- a/radar.md +++ b/radar.md @@ -33,6 +33,7 @@ and includes the specifications for: - [STAC Collections](#stac-collections) - [STAC Items](#stac-items) - [Common Metadata](#common-metadata) + - [Projection](#projection) - [Links](#links) - [Notes](#notes) @@ -57,6 +58,19 @@ If your metadata is already compliant to this profile, you can omit the identifi `stac_extensions` to avoid costly regeneration of the Items. You won't get validation whether all required fields are present, but this could be checked manually in the CEOS assessment/review. +The following STAC extensions are relevant for this profile: + +| Name | Schema URI for `stac_extensions` | Required | +| ----------------- | ----------------------------------------------------------------------- | :------: | +| [CEOS-ARD] | `https://stac-extensions.github.io/ceos-ard/v0.2.0/optical/schema.json` | ✓ | +| [Processing] | `https://stac-extensions.github.io/processing/v1.1.0/schema.json` | ✗ | +| [Projection] | `https://stac-extensions.github.io/projection/v1.0.0/schema.json` | ✓ | +| [Raster] | `https://stac-extensions.github.io/raster/v2.0.0/schema.json` | ✗ | +| [SAR] | `https://stac-extensions.github.io/sar/v1.0.0/schema.json` | ✓ | + +For details about the CEOS-ARD extension, please see the separate [CEOS-ARD extension README](README.md#fields). +The CEOS-ARD extension fields can either be provided in the Collection or in the Items. + ## STAC Collections CEOS-ARD lists a lot of requirements (and fields) that have common values across all generated STAC Items and assets. @@ -69,10 +83,36 @@ All this is still CEOS-ARD compliant as it doesn't require all information to be ## STAC Items +STAC Items must always be valid, but not all STAC Item requirements are covered here, +only additional requirements and mappings to fulfill the CEOS-ARD requirements are listed here: + +| Field Name | Req. | Description | +| --------------- | ----- | ----------- | +| stac_extensions | *n/a* | **REQUIRED.** Must contain [all STAC extensions](#stac-extensions) implemented. | +| geometry | 1.4 | **REQUIRED.** The geometry of the acquisition. | +| bbox | 1.7.8 | **REQUIRED.** The bounding box of the acquisition in WGS84. | + +Generally, CEOS-ARD requests to provide DOIs for various resources. +For STAC, DOIs (e.g. `10.1109/5.771073`) must be converted to URLs (e.g. `https://doi.org/10.1109/5.771073`). +See [Resolve a DOI name](https://dx.doi.org/) for details. + ### Common Metadata ... +### Projection + +The metadata is **required** to specify the coordinate reference system (1.5) and the map projection (1.6) through +either `proj:epsg` or one of the alternatives. The map projection is not required for ST. + +**Deprecation Notice:** In a future version of the version of the projection extension `proj:epsg` will be replaced by `proj:code`. +It is recommended to provide both for now. + +| Field Name | Req. | Description | +| ------------------------------------- | --------- | ------------------------------------------------------------ | +| proj:epsg / proj:wkt2 / proj:projjson | 1.7.11 | **REQUIRED**. One of the fields is required to be provided, recommended is `proj:epsg`. If there's no suitable EPSG code, set `proj:epsg` to `null` and add either `proj:wkt2` or `proj:projjson`. | +| proj:bbox | 1.7.7 | **REQUIRED**. The bounding box of the acquisition in the projection defined in proj:epsg / proj:wkt2 / proj:projjson. | + ## Links ... @@ -80,11 +120,27 @@ All this is still CEOS-ARD compliant as it doesn't require all information to be ## Notes ... - [CEOS-ARD product family specifications]: [Combined CEOS-ARD for Synthetic Aperture Radar, version 1.0]: +[CEOS Missions Database]: +[CEOS Instruments Database]: +[CEOS Measurements Database]: + [STAC]: [Maturity Classification]: +[Common metadata]: +[Media Type]: [Collection Summaries]: [Collection Assets]: + +[Accuracy]: +[Authentication]: +[Classification]: +[CEOS-ARD]: +[Processing]: +[Projection]: +[Raster]: +[SAR]: + +[UDUNITS-2]: