DATA DESCRIPTION

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DATA DESCRIPTION

• The EAST way ...

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SPACE DATA
Data production
Data transmission
Data reception
Data computing archiving
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DATA LIFE CYCLE

• Conceived,
• designed,
• described,
• produced, archived ,...
• and finally accessed !!!

000010010010110111001001011111000011100001101000
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The EAST language

• EAST a language to describe any data
• Precise, rigorous, complete...
• Not a format!!!
• Data format remains free
• Syntax not to be known.
• Tools exist to hide it

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A complete set of tools

• Data description / documentation OASIS
• Data production EAST library (generator)
• Data access EAST library (interpreter)
• High level generic utilities
• ASCII dump
• Data checking
• EAST shell
• Data Update Wizard

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A complete set of tools

• Complete description of any given data
• Access to the values by logical path
• Generic approach / tools
• Generate well formatted data by default
• Platform independence
• Perenniality (CCSDS ISO standard)
• CHEAP

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OASIS

• graphical interface to describe data
• structure
• syntax
• meaning
• helps the user to define his data by
  excluding all the unsaid information
• makes the evolutions easier ...

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OASIS
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OASIS

• OUTPUT
• EAST description - CCSDS / ISO 15889
• Perenniality
• use of the interpreter / generator
• Data Entity Dictionary (DED) - CCSDS
• DED PVL
• DED XML
• Automatic production of the documentation in
  PostScript, XML, Word, Text, PDF

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EAST Library

• GENERATOR
• uses an EAST description file
• writes the data in the right format
• random generation
• cross-platform generation
• API for Ada, C, FORTRAN

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EAST Library

• INTERPRETER
• uses an EAST description file
• reads / checks the data
• navigation in the data file through a tree
  representation (logical access)
• platform independent
• API for Ada, C, FORTRAN

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High level utilities

• ascii_dump
• dumps a data file using an EAST description
• data_checker
• checks the data file using an EAST description
• EAST shell (esh)
• command interpreter based on the EAST library
• Data Update Wizard (DUW)
• graphical creation/update of data files

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What, where, who ??

• The EAST Tools are available via the CNES web
  server http//east.cnes.fr
• Platforms availability
• OASIS SUN-Solaris/PC-NT
• EAST SUN-Solaris, PC-NT,HP-ux, PC-Linux,
  DEC-osf/1 , DEC-Openvms
• Used by many projects
• FREE

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What, where, who ??

• Contact us at
• Supported by the CNES EAST Team
• and the CS company

east_at_cnes.fr
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EAST/OASIS

• Success Story

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SPOT(Earth Observation)

• 1 GERALD file to describe 1 image file. GERALD
  format described in EAST
• Only one format for SPOT 1,2,3 and 4 currently
  updated to cover SPOT 5.
• EAST APIs (interpreter and generator) used by
  sub-contractors for their I/O and for DATA
  simulation and checking.

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SIPAD (CDPP)

• The SIPAD project offers a user web interface to
  access the CDPP (Plasma Physics Data Center)
  data.
• Each project providing data delivers an EAST and
  DEDSL description of its data
• Online documentation produced with OASIS (fullDED
  --gt ded2XML --gt XML --gt HTML)

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SSALTO

• SSALTO is a multi-mission altimetry project.
• Data described in EAST.
• EAST interpreter used in application software
  (helpful to read on a SUN data produced on
  OPEN-VMS)
• Interpreter delivered to JPL
• Very performance demanding

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HELIOS II

• HELIOS II military Earth Observation
• All interface files described with OASIS
• EAST description used for
• Input/output (in application software)
• Data conformance checking
• Data simulation to anticipate integration
• Documentation with ded2xml then html

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ESA/ESRIN

• AMS2 is an ESA/ESRIN project
• Archives management using EAST tools
• DEBAT is a new GSTP (European Research) project
  around EAST technology

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Data dictionaries

• Early use of OASIS to produce preliminary data
  description documents
• ATV Automated transfer vehicle
• Mercator operational oceanography
• Contacts with Pléiades (Earth Observation)
• Contacts with CNES sub-contractors for
  post-processors assistance