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ngEO/sentinel analysis and proposal for update of EOP elements in EO metadata profile

The sentinel product metadata analysis identified a few notions which are missing or not properly supported by the eop metadata profile:
- need to assess the quality via quality tags, rather than via a percentage which is often not applicable or impossible to compute.
- need for some missions, to be able to re-group data items together (e.g. the Sentinel-2 granules are grouped to form products),
- need to manage product metadata differently according to the timeliness (e.g. different services and/or authorizations could be offered, depending on the timeliness)

1- In our opinion, the status QUALITYDEGRADED should not be mixed up with the status indicating the state of the product in terms of data flow (from POTENTIAL to PLANNED to ACQUIRED to ARCHIVED). In fact, the status QUALITYDEGRADED would here replace/overwrite the status ARCHIVED even though the product would still have to be considered as being archived.
Also, the current approach does not allow to indicate that a quality check did occur. The status "ARCHIVED" could mean that a quality check did occur and no degradation where found, or that no checks were done at all. To avoid this , an additional status would be needed: QUALITYOK.
We propose to remove the value QUALITYDEGRADED from the list of possible values for the "Status" attribute.
2- Add an optional imageQualityStatus attribute, with values "DEGRADED", "NOMINAL"
if the attribute is provided with value "NOMINAL, this means the product did passed a quality check with success.
3- Add a new optional attribute imageQualityDegradationTags
Should the imageQualityStatus be DEGRADED, this is to provide additional details on the degradation in the form of tags such as "RADIOMETRY", "GEOLOCATION" to indicate the various types of degradations that are affecting the image. The actual tag values are, for the moment, undefined (up to each quality control system to use its own set of tags)
if tags are provided, this means the product quality is degraded.
4- Add a new optional attribute imageQualityReportURL: this is to provide the URL to an external detailed quality report.
5-Add a new optional attribute "timeliness" in element eop:product/eop:productInformation/ to provide information, in the form of a keyword, on the timeliness of the product, such as "near real time", "rush", ... Actual keyword values to be specified at mission tailoring level. (for Sentinels: RT, NRT, NOMINAL, NRT_10M, NRT_1H, NRT_3H, FAST_24H, ARCH_6H, ARCH_RUSH, ARCH_NORMAL)
6-Add optional attribute productGroupId in eop:/metadataProperty/eop:EarthObservationMetadata: provides a generic way to indicate that the product belongs to a particular group of which the members are eligible for specific aggregations (i.e. All Sentinel-2 granules having the same productGroupId can be assembled together to form a Sentinel-2 end-user product).
7- point 2, 3 and 4 above nicely complete the already existing attributes "imageQualityDegradation" and "imageQualityDegradationQuotationMode" (which we will re-use as well)
For the sake of consistency with the name of the profile itself (EO products), we suggest however to replace the word "image" by "product" in all attribute names. Backward compatibility issues might prevent to implement this particular point. TBD.

Re: ngEO/sentinel analysis and proposal for update of EOP elements in EO metadata profile

In recent discussions concerning orthoimagery it has been raised the requirement to define a set of quality attributes. Any new metadata shall take into account the current work within ISO 19157 and O&M. Furthermore SensorML may be used for describing the process applied to the data, Uncerml for describing the accuracy …

The quality should cover at leats following aspects:
- the data source (lineage)
- the process applied to data from the origin
- the precision obtained after these processes (positional accuracy, spectral, completeness ...)

The DREAM SoW addresses above aspects

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