Standards Change Request
 
Add new keyword BROWSE_USAGE_TYPE                           SCR3-1128.v2
 
Provenance:
-----------
 
Date: 2007-10-31
Author(s): Ed Guinness (Geosciences)
Working Group: Ed Guinness, Steve Hughes, David Heather (ESA/PSA)
 
 
Problem:
--------
 
The PSA is receiving data sets for MEX, VEX, and Rosetta that have more than
one browse product per data product. There are also cases in which one browse
product is associated with more than one data product. The PSA would like to
have information in the browse label and browse index table to:
  
  (1) allow the user to understand how browse images are related to data 
      products when there is not a one-to-one correspondence (i.e., the
      information conveyed by the keyword will be of use to an end user who 
      could (and most probably would) be confused if they see a large number 
      of browse products associated with a single data product).
      
  (2) indicate which browse product should be displayed in the PSA user 
      interface. 
  
  Currently the MEX local data dictionary has a keyword called 
  BROWSE_USAGE_ID that serves this purpose. 
  
Given that VEX and Rosetta would also like to use this keyword, the PSA
proposes that BROWSE_USAGE_TYPE be added into the PSDD. 
 
Current Urgency:
----------------
 
The deadline of December 31, 2007, is given because VEX and Rosetta need
to know by then whether to put this keyword in their local data dictionaries.
 
Proposed Solution:
------------------
 
Add the keyword BROWSE_USAGE_TYPE as defined below from the MEX LDD to the
PSDD.
 
Impact Assessment:
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PDS Standards Reference: None.
Archive Preparation Guide: None.
Proposer's Archive Guide: None.
Planetary Science Data Dictionary: New keyword definition.
PDS Tools: None.
 
Additional Information:
-----------------------
 
None

 
Requested Changes:
------------------
 
OBJECT = ELEMENT_DEFINITION
  NAME = BROWSE_USAGE_TYPE
  STATUS_TYPE = PROPOSED
  GENERAL_DATA_TYPE = IDENTIFIER
  UNIT_ID = NONE
  STANDARD_VALUE_TYPE = DYNAMIC
  MAXIMUM_LENGTH = 40
  DESCRIPTION = "
      The BROWSE_USAGE_TYPE keyword defines whether a browse product is 
      intended to be the primary browse product for an associated data 
      product, or is a secondary browse product, for cases when there are 
      multiple browse products per data product. 
      
      A value of PRIMARY indicates that the browse product is the main 
      browse product for a given data product. A value of OVERVIEW indicates
      that a browse product is associated with, or constructed from, several
      data products (e.g. a mosaic or map produced from several image data
      products). A value of SECONDARY indicates 
      that the browse product is a supplementary browse product for a data 
      product. Choice of which of several browse products is selected as 
      PRIMARY is at the discretion of the data provider (subject to peer 
      review); rationale for the selection could be documented in the 
      label DESCRIPTION of the browse product. SECONDARY browse 
      products cannot exist without a PRIMARY product.

      The keyword is an optional keyword that can be included in the label 
      for a browse product along with the keyword SOURCE_PRODUCT_ID to 
      identify the data product. The value of BROWSE_USAGE_TYPE along with 
      the value of SOURCE_PRODUCT_ID could be used in user interfaces to 
      display browse products resulting from a search or to help users
      understand the relationships between browse products when there is
      more than one browse product for a given source data product."
  STANDARD_VALUE_SET = {
     "PRIMARY",
     "SECONDARY"
     "OVERVIEW"
     }
END_OBJECT = ELEMENT_DEFINITION
END