PDS_VERSION_ID        = PDS3
RECORD_TYPE           = STREAM

OBJECT                = TEXT
   PUBLICATION_DATE    = 2007-09-08
   NOTE                = "Description of contents of EDR directory"
END_OBJECT            = TEXT
END

The EDR directory is present in the EDR archive volume. It contains CRISM 
VNIR and IR EDRs and information on data validation. 

An EDR consists of a part or all of the output from one of the constituent 
command macros that make up one observation tagged by a unique observation 
ID. The data in one EDR represent a consistent instrument configuration 
(shutter position, frame rate, pixel binning, compression, exposure time, 
on/off status and setting of different lamps). There is a single multiple-
band image (suffix *.IMG) stored in one file, plus a detached list file in 
which each record has information specific to one frame of the multiple-band 
image (suffix *.TAB). One label points to both files. 

The multiple-band image has dimensions of sample, line, and wavelength. The 
size of the multiple-band image varies according to the observation mode but 
is deterministic given the macro ID, as described in Data Products SIS. 
Pixels are 16-bit unsigned integer values, most significant bit first. 
Appended to the multible-band image is a binary table of the detector rows 
that were used, as selected by the wavelength filter. This is a one-column 
table, with each row containing one detector row number expressed as a 16-
bit unsigned integer values, most significant bit first.

The detached comma-separated ASCII file contains raw instrument housekeeping 
plus other frame-dependent information, one row per detector frame. 

EDRs are organized into subdirectories by year and DOY, e.g. 2006/2006_350.
An EDR is assigned to a directory based on the start time of the observation
with which an EDR is associated. Several EDRs may result from one 
observation, and all share a common observation ID. These EDRs are grouped 
into subdirectories within a YYYY_DDD subdirectory, named for the 
combination of class type and observation ID unique to a single observation 
(e.g. "FRT00001270"). 

In each subdirectory containing the EDRs for a single observation, there is 
also a text report on data validation for the EDRs generated by each 
detector. 

The file naming convention for an EDR is as follows. See the Data Products 
SIS for the significance of each field in the file name.

(ClassType)(ObsID)_(Counter)_ (Activity)(SensorID)_(Filetype)(version).(Ext)
where:
Class Type = 
     FRT (Full Resolution Targeted Observation)
     HRL (Half Resolution Long Targeted Observation)
     HRS (Half Resolution Short Targeted Observation)
     ASE (Atmospheric Survey EPF)
     MSS (Multispectral Survey, lossy compressed)
     MSP (Multispectral Survey, losslessly compressed)
     MSW (Multispectral Window)
     CAL (Radiometric Calibration)
     FFC (Flat Field Calibration)
     ICL (Calibration source intercalibration)
     STO (Star Observation)
     FUN (Functional test)
     UNK (no valid EDRs within observation that indicate class type)
ObsID= nnnnnnnn, Observation ID, unique for the whole CRISM mission, 
expressed as a hexadecimal number
Counter= nn, a monotonically increasing ordinal counter of EDRs from one 
Observation ID, expressed as a hexadecimal number 
Activity= for an EDR, type of observation, e.g. 
     BInnn - Bias measurements / Macro#
     DFnnn - Dark field measurements / Macro#
     LPnnn - Lamp measurements / Macro #
     SPnnn - Sphere measurements / Macro #
     SCnnn - Scene measurements / Macro #
     T1nnn - Focal plane electronics test pattern 1 / Macro #
     T2nnn - Focal plane electronics test pattern 2 / Macro #
     T3nnn - Focal plane electronics test pattern 3 / Macro #
     T4nnn - Focal plane electronics test pattern 4 / Macro #
     T5nnn - Focal plane electronics test pattern 5 / Macro #
     T6nnn - Focal plane electronics test pattern 6 / Macro #
     T7nnn - Focal plane electronics test pattern 7 / Macro #
     UNnnn - Instrument configuration does not match macro library / Macro #
Sensor ID= S for VNIR, or L for IR
filetype =     EDR
version=     0, 1,...,9, a, ..., z
Ext= IMG or TAB

The file naming convention for the validation report is as follows. 
(ClassType)(ObsID)_(SensorID)_VALIDATION.TXT