Data Set Overview
  =================
    This data set contains raw Surface Stereo Imager (SSI) operational data. 
    If 12 to 8 bit scaling was commanded, these images HAVE NOT been 
    transformed back to 12 bits. These images are only used to assess the 
    morphology, topography, and geologic context of the lander site and
    should not be used for quantitative scientific purposes.

    More information is found in ALEXANDERETAL2008, LEMMONETAL2007, and
    LEMMONETAL2008.

  Processing
  ==========
    This documentation uses the Committee on Data Management and Computation 
    (CODMAC) data level numbering system. The Phoenix Camera Payload EDRs 
    referred to in this document are considered Level 2 or Edited Data 
    (equivalent to NASA Level 0). The EDRs are to be reconstructed from 
    Level 1 or Raw Data, which are the telemetry packets within the project 
    specific Standard Formatted Data Unit (SFDU) record. They are to be 
    assembled into complete images, but will not be radiometrically or 
    geometrically corrected.

    EDR data products will be generated by MIPL using the telemetry 
    processing software mertelemproc at JPL. The EDRs produced will be raw 
    uncalibrated data reconstructed from telemetry packet SFDUs and 
    formatted according to this SIS. Meta-data acquired from the telemetry 
    data headers and a meta-data database will be used to populate the PDS 
    label. Missing packets will be identified and reported for 
    retransmission to the ground as partial datasets. Prior to 
    retransmission, the missing EDR data will be filled with zeros. The EDR 
    data will be reprocessed only after all partial datasets are 
    retransmitted and received on the ground. In these cases, the original 
    EDR version will be overwritten.

  Data
  ====
    The data packaged in the camera data files will be decoded, decompressed 
    camera image data in single frame form as an Experiment Data Record 
    (EDR). The Full Frame form of a standard image data file has the maximum 
    dimensions of 1024 lines by 1024 samples.

    1) Full Frame EDR
       Full Frame EDRs are stored as 16-bit signed integers. If 12-to-8
       bit scaling is performed, then pixels are stored in 16-bit format
       and only the last 8 bits of the 16-bit integer are used.

    2) Thumbnail EDR
       Thumbnail EDRs are stored as 16-bit signed integers or 8-bit
       unsigned integers. If 12-to-8 bit scaling is performed, then
       pixels are stored in 16-bit format and only the last 8 bits of
       the 16- bit integer are used. The Thumbnail EDR is a sized down
       version of the original acquired image (i.e., camera returned
       pixel data), and size of the binary EDR image data is variable.
       However, the original acquired image is not always downlinked.
       The main purpose of a Thumbnail EDR is to provide an image
       summary using a very low data volume compared to the original
       image.

    3) Sub-frame EDR
       Sub-frame EDRs are a subset of rows and columns of the
       1024 x 1024 full frame image. Sub-frame EDRs are stored as 16-bit
       signed integers. If 12-to-8 bit scaling is performed, then pixels
       are stored in 16-bit format and only the last 8 bits of the
       16-bit integer are used.

    4) Downsampled EDR
       A downsampled EDR is a smaller version of the 1024 x 1024 full
       frame or subframed image using the following methods: 1) nearest
       neighbor pixel averaging, 2) pixel averaging with outlier
       rejection or 3) computing the median pixel value. Downsampled
       EDRs are stored as 16-bit signed integers. If 12-to-8 bit scaling
       is performed, then pixels are stored in 16-bit format and only
       the last 8 bits of the 16-bit integer are used.

    5) Reference Pixels
       The onboard CCD array has 16 pre-Reference dark pixels (12-bits)
       located at the beginning and 15 post-Reference dark pixels
       (12-bits) located at the end of each row. The values of these
       pixels indicate the bias level of the camera at the time of each
       observation. The Reference Pixel images were losslessly
       compressed for downlink. For complex design reasons, the last
       post-Reference pixel is a copy of the next-to-last
       post-Reference pixel. Following the last post-Reference
       dark pixel, at the very end of each row, is the camera hardware
       serial number (left-shifted by 4 bits if 12-bit data).

  Software
  ========
    Phoenix Camera Payload downlink processing software is focused on rapid
    reduction, calibration, and visualization of images in order to make
    discoveries, to accurately and expeditiously characterize the geologic 
    environment around the lander, and to provide timely input for 
    operational decisions concerning target selection. Key software tools 
    have been developed at JPL by the MIPL, SSV, and APSS groups, at NASA 
    Ames, and at the USGS/Flagstaff. 

    PDS-labeled images and tables can be viewed with the program NASAView, 
    developed by the PDS and available for a variety of computer platforms 
    from the PDS web site
    http://pdsproto.jpl.nasa.gov/Distribution/license.html.
    There is no charge for NASAView.

  Media/Format
  ============
    The data set will initally be delivered and kept online. Upon Mission 
    completion, the SSI EDRs will be delivered to PDS on DVD.

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