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For the vegetation products INRA provided the vegetation 
variable ATBDs and HYGEOS provided the albedo and 
filtering/gap filling ATBDs. For the soil moisture product TU 
Wien provided the SW1 ATBD. 
Secondly, the operational centres expressed their interfaces 
requirements. 
VITO provided the coding specification document, which 
explains the software convention that shall be used (general 
coding rules, computer platform issues, filename and directory 
structure conventions) and the Product Output Format 
document, which specifies the format used at VITO and gives a 
detailed description of files contents and name conventions. 
IM provided the Algorithm Plugging Interface Document 
(APID), which includes their software conventions, and their 
Product Output Format document. 
Thirdly, TU Wien delivered to ONES an IDL prototype used 
for the development of the SWI VI product line. This prototype 
has been used as an example of algorithm implementation and 
for the technical qualification of the product by cross-checking 
of prototype output and test data, before delivery of them to the 
validation team. 
Fourthly, the vegetation products derive from an existing 
processing line named Cyclopes, developed and used by the 
former land surface thematic centre POSTEL [2 & 3]. This 
processing line has been used until 2009 to produce vegetation 
variable products from VGT instrument data until year 2007 
(see figure 2). This issue of vegetation variables is named 
version 0 (V0). 
CNES has taken over the former activities around Cyclopes 
and the version V0 is used as the baseline from the 
development of new vegetation variable processing lines. 
Figure 2 : FCover map (0 = white = bare soil, 1 = dark 
green = fully vegetated) from Cyclopes V0, © 
POSTEL/INRA 
INRA delivered to CNES a Matlab prototype of the Neural 
Network used at the last stage of the processing line, in order 
to verify the implementation of the new structure and weights. 
2.3 Development process 
During the design phase, CNES gathered requirement set 
(ATBD, operational interface, output format, ...) and made a 
call for proposal for the development and test data phase. Vega 
Technologies company, based in Toulouse (Fr), has been 
selected in June 2009 and has developed the first versions of 
processing lines. 
The development is performed in an industrial environment for 
two reasons. 
The re-use of Cyclopes V0 needs a detailed and accurate 
knowledge of the existing processing line, in order to modify 
efficiently the six processing steps providing the albedo 
product (Level 3A) and the four vegetation products (Level 3B) 
from the VGT level 1 data. 
More important, the industrial context includes a better quality 
frame by the use of external reviews at different steps of the 
development process. CNES has performed three reviews with 
its subcontractor, where experts from the BioPar partners were 
present. 
The System Requirement Review took place in July 2009 and 
demonstrated how far: 
• the Service Specification answers to the User 
Requirements Document (URD) 
• the processing line design answers to the Service 
Specification requirements 
• the external interfaces and operation requirements 
are taken into account during the development 
• the Service Validation Plan (SVP) implements the 
necessary verification steps to validate the 
requirements of the URD and the commitments of 
the Service Specification. 
VEGA Technologies has shown his deep knowledge of the 
existing processing line of the vegetation variables and was 
able to propose discerning changes to match the specifications 
and the requirements of the production centres, and also a 
rigorous methodology of validation based upon unit & 
integration tests, and upon scientific analysis of the output 
using tools including visual control, and statistic data analysis 
Due to the huge reuse of Cyclopes processing line, the 
Preliminary and Critical Design reviews have been merged in 
one review which took place in October 2009. The purpose of 
the Preliminary Design Review is to assess and approve the 
preliminary design and assess the readiness to start the 
implementation phase. The purpose of the Critical Design 
Review is to assess and approve the detailed design of the 
processing lines and the detailed definition of the interfaces. 
The P-CDR review raised 50 questions & answers from the 
review group, which have been analyzed and discussed. The P- 
CDR concludes that all the objectives are fulfilled, excepted 
for BUFR interfaces of the SWI product (lack of detailed 
format). 
The Industrial Acceptance Review address the result of the 
acceptance test (installation from scratch and testing of the 
processing line) performed at the sub-contractor premise and at 
CNES. The IAR has been performed and accepted for the 
vegetation variables and is currently performed for the SWI 
product. 
After this milestone, CNES delivers the processing lines to 
VITO and IM, with a support of the subcontractor if needed. 
Then VITO and IM will organize the Validation Readiness 
Review (VARR) and the Operational Readiness Review (ORR) 
of their processing line. CNES will participate in these 
reviews.