Data Set Overview : The High Resolution Imaging Science Experiment (HiRISE) is one of  the remote sensing instruments on the Mars Reconnaissance Orbiter  (MRO) spacecraft that acquires orbital observations of the Martian  surface during a two earth-year primary mapping phase. MRO,  successfully launched in August 2005, arrived at Mars in March  2006. Following orbit insertion the spacecraft went into an  aerobraking period to achieve a 250 x 315 kilometer near-polar  orbit suitable for the Primary Science Phase (PSP) mapping that  started in November 2006. Since the start of PSP HiRISE has been  continuously operating acquiring 10-20 observations per day. The HiRISE team is responsible for maintaining an updated dataset  of the best version of its science data until meaningful  changes in data calibration no longer occur and to release data in  an appropriate manner for public access including their final  deposition to NASA's Planetary Data System (PDS). In carrying out  these responsibilities, the HiRISE team creates two types of  standard data products: 1) Experiment Data Record (EDR) products  and 2) Reduced Data Record (RDR) Products. This document describes  the RDR standard products. These Reduced Data Record (RDR) products are radiometrically- corrected images resampled to a standard map projection. They  are formatted and organized according to the standards of the PDS.  The RDR image is stored in the JPEG2000 format recently accepted  by the PDS. The JPEG2000 images are accompanied by a PDS detached  label providing supporting information about the observation. The HiRISE RDR products comply with the PDS standards for file  formats and labels, specifically using the PDS image object  definition. The RDR image files, formatted according to the  JPEG2000 standard, use 'JP2' as their filename extension. They are  accompanied by PDS labels; files that have the same name as the  image data file but use 'LBL' for their filename extension. The  label file provides image data characterization and science  metadata information about the observation. Additionally, the  ancillary data files that accompany the RDR products and the  archive volume structure are in conformance with PDS standards. RDR image data are stored in the JPEG2000 ISO/IEC Part 1 standard  format (http://www.jpeg.org/jpeg2000/), which was accepted by the  PDS standard in October 2005. The JPEG2000 standard offers  benefits distinctly advantageous for storage and access to very  large images. With HiRISE RDR products reaching sizes exceeding  30,000 x 70,000 pixels the use of JPEG2000 was recognized as a  suitable solution for the storage and distribution of these data  products. Advantages include excellent compression performance,  multiple resolution levels from a single image data set,  progressive decompression quality layers, lossless and lossy  compression (HiRISE RDR products use lossless compression per the  PDS Standard), pixel datum precision up to 38 bits, multiple image  components (or bands), and selective image area access. These  features are achieved by the use of a sophisticated image coding  system based on discrete wavelet transforms (DWT) combined with  other coding techniques to generate a JPEG2000 codestream that can  be rendered to image pixel rasters using  inverse transform algorithms.  Processing : Science data from the MRO payload experiments are packetized on  the spacecraft, transmitted to Earth through the Deep Space  Network, and sent to the Jet Propulsion Laboratory (JPL) through  ground communications. The JPL Multi-Mission Operations Facility  converts the packetized data back to the original science data  format as produced by the instruments. For HiRISE observations, a  raw science product is created for each CCD/Channel involved in  the observation. The data are stored at JPL's Raw Science Data  Server (RSDS) for access by the science teams. At the HiRISE Operations center (HiROC) we have developed a ground  data system that provides automated methods for retrieving and  processing our images. Science data are automatically retrieved  from the RSDS and passed to a series of pipeline procedures  managed under the Conductor environment  (http://pirl.lpl.arizona.edu/software/Conductor.shtml). The  pipelines generate intermediate products used for image evaluation and standard data products for science analysis. Additionally, the pipelines populate HiRISE-catalog EDR and RDR product tables and observation geometry tables with relevant metadata. The product and geometry tables are used to generate index tables provided as part of the product distribution to the PDS. The HiRISE team verifies  observations were properly acquired and science objectives  achieved. Missed targets or observations with poor viewing  conditions are flagged for reacquisition at a later time. HiROC  uses the Integrated Software for Imagers and Spectrometers (ISIS)  system in the pipeline processing. ISIS contains a wide range of  tools including radiometric calibration and cartographic  processing procedures. The ISIS components applicable to HiRISE  include radiometric calibration, map projection transformation,  image mosaicking, camera pointing correction, and general image  enhancement, display, and analysis tools. For more information on  this freely available image analysis package, see the ISIS web  site (http:// isis.astrogeology.usgs.gov/).  HiROC's pipeline processing starts when the FEI_WatchDog procedure,  responsible for periodically monitoring the RSDS, determines a raw  science data file is ready to be downloaded from the RSDS and  passes the name of the product to the HiDog pipeline (Downlink  Organizer). The HiDog pipeline retrieves the data product then  submits the file name to the EDRgen pipeline (EDR generator) for  creating the EDR product and populating the EDR product table with  metadata about the product. The HiRISE Observation software used toproducts is described in detail at http://pirlwww.lpl.arizona.edu/software/HiRISE/ and can be obtained on request. The EDR_Stats pipeline creates an ISIS file and generates image statistics that are placed in the EDR  products table. The HiCal pipeline performs the radiometric  correction (see Section 4.1.1), and generates a browse and  thumbnail image of the EDR product to be used by the HiRISE and  PDS Imaging Node data-distribution web services. When the HiCal  pipeline determines two channel files of a CCD have been  calibrated the file names are passed on to the HiStitch pipeline  for creating an intermediate CCD image file. HiStitch additionally  adjusts the channels to radiometrically match at the seam where  the two channels come together. When the HiStitch pipeline  determines all of the observation's CCDs have been stitched  together for a filter set then the HiccdStitch pipeline is invoked  to create an intermediate product with the CCDs stitched together  to form a single image for the color filter. HiccdStitch  additionally adjusts the CCD images to radiometrically match the  overlapping areas of adjacent CCDs. Finally HiccdStitch creates an  intermediate JPEG image for evaluation by the HiRISE team.   At this point in the processing the EDR-validation step occurs. To  continue the pipeline processing the reconstructed SPK and CK  SPICE kernels, providing information about the observing viewing  geometry and spacecraft ephemerides, need to be retrieved from the  NAIF Node though HiROC's HiSPICE subsystem. Reconstructed SPICE  kernels are generally provided to the MRO science teams one to two  weeks after the observation was acquired. The HiGeomInit pipeline  extracts the spacecraft ephemeris kernel (SPK) and C-matrix  pointing kernel (CK) data from the SPICE files and transfers the  data to the CCD image files for geometry processing by the  pipelines that follow. Additionally HiGeomInit populates the  observation geometry table with viewing geometry and coordinate  metadata. The RedGeom and ColorGeom pipelines perform geometric  processing on individual CCD images. The RedMosaic and ColorMosaic  pipelines mosaic the projected CCD images to form an observational  image. Additionally these pipelines create RDR-product browse and  thumbnail jpeg images for HiRISE and PDS Imaging Node web-based  distribution services. The last pipeline step, RDRgen, creates  the JPEG2000 formatted JP2 image file accompanied by a PDS detached label file and populates the RDR product table with information about the product. The software for converting a raw PDS file with an  attached label to PDS label and JP2 files is available on request. Following a final validation step the EDR and RDR  products are releasable to the PDS and science community. Radiometric Calibration Processing ---------------------------------- The radiometric calibration-correction procedure is described here  at a high level. A detailed description will be provided in a  future HiRISE calibration paper. The radiometric calibration  correction is performed on each individual HiRISE channel file  (EDR) correcting for instrument offset, dark current, gain, then  converting to I/F reflectance. The first step in the calibration,  carried out by the ISIS hiclean program, corrects for instrument  dark current and offset. The hiclean program uses the ancillary  calibration data (dark and mask pixels that accompany the science  data to compute corrections in both the column (sample) and row  (line) directions. The mask pixels, positioned at the start of the  instrument output, provide dark current information for each  column. The dark pixels, positioned at the end of each image row,  capture the time dependent dark current and offset instrument  drift. The ISIS hical program then applies an intra-channel B0 (additive  dark current matrix) and A0 (multiplicative gain matrix)  correction for each column in the image array. The hical then  converts the pixel values to I/F (intensity/flux, I/F : 1 for a  100% ideal lambertian reflector viewed normal to the surface) as  described below:  For: H : dark current and offset corrected image, output of hiclean B0 : intra-channel dark current correction (TDI & BIN dependent) A0 : intra-channel gain correction (TDI and BIN dependent) G : global gain correction, normalizes CCD/channels L : observation line time I : I/F conversion factor at Sun-Target distance of 1.5 AU AU : Mars-to-Sun distance (AU) at time of observation Z : radiometrically corrected image in I/F units The correction is:  Z : ([H-(B0_L)]/L)_A0_G*I*(1.5/AU)2 Instrument instabilities result in radiometric mismatches requiring  additional corrections for the varying column-to-column, channel-to- channel, and CCD-to-CCD sensitivities. Residual column-to-column  variations are corrected by first computing the mean value for each  column in an image array. The mean-value one-dimensional array is then  high-pass filtered to eliminate low-frequency information due to scene  content. The result of the high pass filter is then subtracted from  the image array. CCD channels are adjusted to radiometrically match at  the seam where the two channels come together (performed by the  HiStitch pipeline). The CCDs are then radiometrically matched one to  the other by matching the overlapping areas of adjacent CCDs ( performed in the HiccdStitch pipeline).  Geometry Processing -------------------  There will typically be two RDR standard products per observation: a  single-color RDR product built from the operating red-filter CCDs, and  0a three-color RDR product if the blue-green and near-infrared CCDs  were additionally operating. In rare cases a two-color RDR product  will be created if only two color filters were commanded.  The geometric processing corrects for the optical distortion and  projects the observation from spacecraft viewing orientation to a map  coordinate system. For RDR products the Equirectangular or Polar  Stereographic projections are used. The geometry processing, carried  out by ISIS program cam2map, uses cubic convolution resampling.  Geometry processing employs the NAIF toolkit  (http://naif.jpl.nasa.gov) and uses reconstructed SPICE kernels  generated by the MRO project. The geometry processing uses the MOLA  Digital Terrain Model to improve the camera pointing intercept  position on the Martian surface.  In the geometric processing, individual channel images are stitched  together to form CCD images using the ISIS program histitch. The  spiceinit program searches through the available NAIF kernel set and  applies planet and spacecraft ephemeris data to establish geometric  properties of each CCD image CCD images are then individually map  projected with camp2map and mosaicked together using himos forming an  image of the entire observation. Resulting image maps vary in size  depending on the number of CCDs commanded, number of lines acquired  and the binning mode of the images. RDR products can be very large, at  times exceeding 30,000 x 70,000 pixels. Observations with mixed  binning modes are resampled to the same pixel scale depending on the  minimum binning used in the observation. For the Transition Orbit  Phase (TRA) and Primary Science Phase (PSP), observations with  unbinned imaging are uniformly mapped to a constant 0.25 m/pixel  resolution (0.50 m/pixel for minimum binning 2 and 1.0 for binning 4).  The Aerobraking phase images (AEB) are mapped to a pixel scale  depending on the spacecraft altitude and the minimum binning.  For three-color imaging additional processing steps are required to  create the three-color RDR products. Spacecraft jitter exists at a  higher frequency than can be captured by the reconstructed pointing  kernels. The color CCDs see a point on the planet surface separated  by ~120 milliseconds resulting in jitter-induced pointing  misalignments not captured by the reconstructed pointing matrix. To  minimize color misregistration the blue-green and near-infrared  filters are spatially matched through a two-step empirical approach.  In the first step the blue-green and near-infrared filter CCD images  (usually acquired at a higher binning level than the red-filter CCDs)  are scaled to match the binning of the red-filter CCD imaging. Next,  an ISIS program, hijitreg, applies an image coregistration process  constructing a control network that spatially maps the blue-green and  near-infrared filter imaging to the red filter imaging. The control  network is provided to the second step responsible for resampling the  blue-green and near-infrared filter images to the red. The program,  slither, performs a one-dimensional cubic-spline transformation  performing translational shifts on otherwise undistorted individual  lines. Once the blue-green and near-infrared images are spatially  registered to match the red imaging, the images go through the same  geometric processing to create a map-projected image as described  above. The BANDWIDTH keyword in the PDS labels identifies the color  filters used in the image product. The CENTER_FILTER_WAVELENGTH and  BANDWIDTH keywords provide information about the spectral range of  each filter The storage order for the the three-color products is  Near Infrared (band 1), Red (band 2), and blue-gree (band 3).  Data : The HiRISE EDR products act as the input source to the RDR  processing.  Ancillary Data : Generation of the RDR products relies on the MRO-project deliveries for the Spacecraft Ephemeris (SPK kernels) and MRO spacecraft pointing files (CK kernels) Coordinate System & Cartographic Standards : The HiRISE RDR products are compatible with the cartographic standards  and mapping conventions used by the MRO CRISM map products. When  spatially registering map products produced by the two instrument  teams only a translation and scale change are required. The  coordinate system used is planetocentric latitude and east positive  longitude direction. The planetocentric latitude is the angle from the  equator to a point on the surface of an oblate planet. The longitude  increases from west to east (left to right). The planetary constants used in the camera model to produce the HiRISE  RDR products are obtained from the NAIF SPICE planetary constants  kernel pck0008.tpc. The Mars constants of particular importance are  the right ascension and declination of the pole, the prime meridian,  rotation rate, and radii. The constants used are: BODY499_POLE_RA : ( 317.68143 -0.1061 0. ) BODY499_POLE_DEC : ( 52.88650 -0.0609 0. ) BODY499_PM : ( 176.630 350.89198226 0. ) BODY499_RADII : ( 3396.19 3396.19 3376.20 ) Additionally, the SPICE kernel de405.bsp was used for the ephemeris  data for Mars. Two map projections are used in the HiRISE RDR products:  Equirectangular and Polar Stereographic.

Confidence Level Overview : Known problems are TBD. Review : This archival data set has been examined by a peer review panel prior to its acceptance by the Planetary Data System (PDS). The peer review has been carried out in accordance with PDS  procedures. Data Coverage and Quality : RDR products are the permanent record of the HiRISE observations  that are radiometrically corrected an map projected. The observational coverage on the Martian surface is dependent on the instrument operating modes of the observation. The largest coverage at 300 kilometer spacecraft altitude is about 6 km crosstrack and 37 kilometers downtrack.   During the Primary Science Phase of MRO operations, HiRISE is expected to image about 1% of the surface of Mars. Observations are carefully selected to optimize science return.