1. Introduction This data set has been generated by the Jet Propulsion Laboratory's (JPL) Science Digital Data Preservation Task (SDDPT) by migrating valuable space science data from older, deteriorating magnetic tapes to CD-ROM. The primary goal of the SDDPT is to reduce the amount of data stored on magnetic tapes, preserve valuable science data and make it more accessible to the user. This data set resides on a series of CD-ROM volumes containing Viking Lander high resolution mosaics, stereo images and range data sets for archival. Each volume in the set includes ancillary information in addition to instrument data. The input for the compact discs was magnetic tape which, in most cases, was at least 15-20 years old. Accompanying each tape on the disc, there is a log file which documents SDDPT processing history. Therefore, if problems were encountered while recovering the data from tape, they will be documented in the log file. The SDDPT is not reformatting the data. However, it has been made readable in standard ISO 9660 format on the compact disc useable on a variety of platforms. Three copies of each title will be generated: one intended for deep archive at the National Space Science Data Center in Goddard, MD; one as a backup copy at the JPL Archives; and one to reside with the data user. In the cases where a planetary data set is likely to have many users, the "user" disc will be sent to the cognizant discipline node of the Planetary Data System. For further information about the SDDPT and the process by which valuable data sets were identified, see the SDDPT Inventory/Evaluation Phase Final Report,(JPL Document D-10753) or contact: Amy Hochstettler Culver MS 168-514 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 818-397-7363 Electronic mail addresses: SPAN: MIPL3::ADH875 Internet: ADH875@ipl.jpl.nasa.gov 2. Data Set Information and SDDPT History The input tapes to this CD volume set contained special products generated from processed Viking Lander imaging data. In particular, the high resolution archive mosaics, stereo images and the range data sets are included. The data files are comprised of variable length records - for more detail on the exact file structure, consult the COPY_LOG file accompanying each tape. The file RNG_INFO.TXT is included on each CD in the series, and it correlates the tape ID and a description of the tape's contents, where available. On the last CD of the series, the archive CD volume is also included for each tape. In order for the user to locate a particular file on the appropriate CD volume, he or she can check the jewel box backliners to determine the input tapes used to create the particular CD, or consult the RNG_INFO.TXT file. 2.1 Handling of duplicate tapes The original tapes had prefixes DNM, DNR, DNS, FNM and FNS. All of the prefix sets except DNR had two copies of each tape, a 0xx version and a 1xx version. (For example, the data on DNM-001 was identical to the data on DNM-101.) When the data on the 0xx version of the tape was read without errors, it was the version archived on the CD. If there were problems reading the 0xx version tape, the 1xx tape was also read, and the best copy was archived on the CD under the name of the 0xx version of the tape. The DNR tapes had both the 0xx and 1xx copies for tapes 1 through 35, but DNR tapes 36 through 43 did not have a 0xx version. Therefore DNR-001 through DNR-035 have been archived on the CD under their 0xx tape name, and DNR-136 through DNR-143 were archived under their 1xx version names. 2.2 Reference Documentation Documents which may be useful for interpreting the Viking Lander high resolution mosaics, stereo images and RNG data sets include, but are not limited to: Levinthal, Elliott C. and Jones, Ken L., "The Mosaics of Mars as Seen by the Viking Lander Cameras", NASA Contractor Report 3326. Tucker, Robert B., "Viking Lander Imaging Investigation: Picture Catalog of Primary Mission Experiment Data Record", NASA Reference Publication 1007, February 1978. NASA Contractor Reports 1137 and 1068v.1 & 2. 3. Disc Format Each CD-ROM disc has been formatted so that a variety of computer systems (e.g. IBM PC, Macintosh, Sun, VAX) may access the data. Specifically, the discs are formatted according to the ISO 9660 level 1 Interchange Standard, and file attributes are specified by Extended Attribute Records (XARs). For computer software that fully supports XARs, access to the CD-ROM volume will be straightforward; the disc will appear to the user to be identical to a file system of directories, subdirectories and data files. Some computer systems that do not support XARs will ignore them; others will append the XAR to the beginning of the file, in which case the user must read past the first 512 bytes of the file. For further information, refer to the ISO 9660 Standard Document: RF# ISO 9660-1998, 15 April 1988. 4. CD-ROM Contents The files on this CD-ROM are organized in one top-level directory with several subdirectories. The following table shows the structure and contents of these directories. In the table, directory names are enclosed in square brackets ([]), upper-case letters indicate an actual directory or filename and lower-case letters indicate the general form of the directory file names. Top-level directory | |-AAREADME.TXT - This text file containing general information. | |-[INDEX] - Directory containing a text file to simplify searching for | | specific data. | | | |-RNG_INFO.TXT- A text file describing basic information about the input | data. In this file, tape IDs are correlated with their | descriptions. On the last CD in the series, the CD volumes | are also listed. | |-[dnm_aaa_bbb] - The tapes are grouped into directories based on on prefix | | sets. This is done in order to minimize delays reading | | the CD due to a large number of directories all appearing at | | the same level of the CD. In this example, dnm is the | | prefix of all the tapes included in the directory, aaa | | represents the lowest tape number in the directory, bbb is | | the highest tape number included in the directory. | | | |-[dnm_xxx] - The data files are arRNGd into directories based on the | | | INPUT TAPE IDS. The user can locate particular data based on | | | the tape's description by using the RNG_INFO.TXT file. | | | | | |-[DATA] - The subdirectory containing the data files. | | | | | | | |-dnm_xxx.yyy;1 - Each data file has a unique name. The file | | | name (dnm_xxx) represents the input tape id, and the file | | | extension (yyy) indicates the file number on the input tape. | | | Example: DNM_008.001 is the file originally located on | | | tape DNM_008, file 1. | | | | | |-[LOGS] - The subdirectory containing a log file describing tape | | | | copying history. | | | | | | | |- COPY_LOG.yyy;1 - The tape copying history has been preserved for | | | each data file so that the user can determine if some | | | data has been skipped or lost due to problems reading the | | | input tape. There will be a COPY_LOG in the directory | | | covering each file on the input tape. If there is only one | | | log file in the directory, it covers all files on the tape, | | | otherwise the file extension (yyy) indicates the file number | | | on the input tape. If problems were encountered during the | | | copying process, the entire history will be preserved in | | | this log file. 5. Text Files All document files and copying logs contain a carriage return character (ASCII 13) and a line feed character (ASCII 10) at the end of each record. This allows the files to be read by the MacOS, DOS, Unix, and VMS operating systems. 6. Recommended CD-ROM Drives and Driver Software (Note that the following list is not inclusive.) VAX/VMS Drive: Digital Equipment Corporation (DEC) RRD40, RRD42, or RRD50. Driver: DEC VFS CD-ROM driver V4.7 or V5.2 and up. Note: The driver software may be obtained from Jason Hyon at JPL (Files are: JPLPDS::DISK$USER1:[JHYON]VFS*.A). It is necessary to use this driver to access the XARs on the CD-ROM. VAX/Ultrix Drive: DEC RRD40, RRD42, or RRD50. Driver: Supplied with Ultrix 3.1. Note: Use the "cdio" software package (in "~ftp/src/cdio.shar" from the "space.mit.edu" server). IBM PC Drive: Toshiba, Hitachi, Sony, or compatible. Driver: Microsoft MSCDEX version 2.2. Note: The newest version of MSCDEX (released in February 1990) is generally available. Apple Macintosh Drive: Apple CD SC (Sony) or Toshiba. Driver: Apple CD-ROM driver. Note: The Toshiba drive requires a separate driver, which may be obtained from Toshiba. Sun Micro Drive: SUN Microsystems (Sony). Driver: SUN CD-ROM Driver. Note: There is a patch to support structured files. >the following error, when >trying to do a "ls" on its directory contents: > 'hsfs: filetype(0X8) not supported'. > The files that cause the error message are structured files. They are organized in records (fix or variable length). Applications need to retrieve additional file attributes (fix or variable length, and maximum record length) from these files in order to access the contents correctly. Unfortunately, UNIX can only handle stream files (unstructured byte stream). There is currently no application interface to access the extended file attributes and data records in a record format file. (Note: Philips is coming up with an X/Open specification (XCDR) to provide an API to access the ISO 9660 CD-ROM format Disc. It is too early to tell whether it will be approved or not). The design decision when implementing the CD-ROM file system was to ignore all record format files stored in a CD-ROM. This is obviously a mistake. The best way is at least to allow users to access these files. The following is a patch for SunOS 4.1 Sun4c (SPARCSTATION) to correct the above problem: acuraintegra# adb -w vmunix >>>> hs_parsedir+9c?X _hs_parsedir+0x9c: ba0da0ee >>>> hs_parsedir+9c?Wba0da0e6 _hs_parsedir+0x9c: 0xba0da0ee = 0xba0da0e6 >>>> hs_parsedir+14c?X _hs_parsedir+0x14c: ba0da0ee >>>> hs_parsedir+14c?Wba0da0e6 _hs_parsedir+0x14c: 0xba0da0ee = 0xba0da0e6 >>>> $q Note: you can also patch hsfs_node.o with the above patch. The patch for SunOS 4.0.3c (SPARCSTATION) is similar: hs_parsedir+9c?X _hs_parsedir+0x9c: ba0de0ee hs_parsedir+9c?Wba0de0e6 _hs_parsedir+0x9c: 0xba0de0ee = 0xba0de0e6 hs_parsedir+14c?X _hs_parsedir+0x14c: ba0de0ee hs_parsedir+14c?Wba0de0e6 _hs_parsedir+0x14c: 0xba0de0ee = 0xba0de0e6 $q The following is the patch for the sun3: adb -w hsfs_node.o hs_parsedir+56?X _hs_parsedir+0x56: ee6612 hs_parsedir+56?We66612 _hs_parsedir+0x56: 0xee6612 = 0xe66612 hs_parsedir+e4?X _hs_parsedir+0xe4: ee6612 hs_parsedir+e4?We66612 _hs_parsedir+0xe4: 0xee6612 = 0xe66612 $q 6. Who to Contact for Information For questions about how to read CD-ROMs: Jason J. Hyon MS 525-3610 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 818-306-6054 Electronic mail addresses: SPAN: JPLPDS::JHYON Internet: JHYON@jplpds.jpl.nasa.gov NASAmail: jhyon For questions concerning the Viking Lander high resolution mosaics, stereo images and range data sets: Ken Jones MS 168-414 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 818-354-2242 Electronic mail addresses: Internet: Ken_Jones@iplmail.jpl.nasa.gov or the Principal Investigator, Thomas Mutch at Brown University. For questions concerning the distribution of the Viking Lander processed imaging data contact the Planetary Data System's Imaging Node: Leslie Pieri MS 168-522 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 818-354-8320 Electronic mail addresses: SPAN: MIPL3::LJP051 Internet: LJP051@ipl.jpl.nasa.gov OR Eric Eliason United States Geological Survey Branch of Astrogeology 2255 North Gemini Flagstaff, AZ 86001 Electronic mail addresses: SPAN: ASTROG::EELIASON Internet: EELIASON@astrog.span.nasa.gov