ISOCAM Interactive Analysis User's Manual Version 5.0 - ISO - ESA

Chapter 11
Introduction to CIA data analysis
This chapter provides an overview of the CIA data analyses processes vis-à-vis data structures
and data products.
11.1 CIA Processing Overview
Figure 11.1 provides an overview of the general analysis procedure you will follow to reduce
your data products to presentable images. The three processing steps are data preparation,
data calibration and image analysis & display – subsequent chapters describe each of these
steps. Note that the level of processing depends on the data products you begin with, e.g. you
don’t need to perform data calibration on the images in the AAR data products. Also remember
that CIA data structures are the kernel of CIA processing. Each processing step is performed on
a particular data structure and the structures evolve as the data are further reduced. Hopefully,
all this will become clear as you read on:
1. Data preparation (also known in CIA as data slicing) refers to the process of extracting
data from the ERD or SPD data products, translating telemetry coded parameters into a
user-friendly format, and placing all these data in an SPD SCD. There are two paths to
producing SPD SCDs from data products:
(a) Automatic data slicing:
• ERD data products are converted into ERD SCDs with erdtoscd andthenthe
ERD SCDs are converted into SPD SCDs with erd2spd.
• SPD data products can be directly converted into SPD SCDs with spdtoscd.
These methods are referred to as automatic data slicing methods (see Section 12.2).
(b) Data slicing with x slicer:
ERD data products can be directly converted into SPD SCDs with the widget-based
interface x slicer. (see Section 12.3).
x slicer requires more effort to use than the automatic slicers, but has greater flexibility
and a nice user interface. However, regardless of which way you choose to create SPD
SCDs, the end result should be the same. See the referenced sections, for the method of
your choice.
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