User's Guide

CKTRANS

Checks images transferred over the network.

Function:

Checks AVHRR images that have been transferred over the network from the specified receiving station to ensure the images are the correct size.

Parameters:

Subcommand -BAA:
Checks all images transferred from Buenos Aires, Argentina (through Miami University). Valid images are moved to the ADAPSACQ directory (See User Note 8).

INDIR(/SGS4/KM1/XFER/BAA)
Input directory. Directory where the images to be checked are located.

NIMAGES
Number of images. The number of images checked is returned in the specified TAE INTEGER variable.
Subcommand -LSU:
Checks all images transferred from Louisiana State University. Images with the correct file size are moved to the ADAPSACQ directory (See User Note 6).

INDIR(/SGS4/KM1/XFER/LSU)
Input directory. Directory where the images to be checked are located.

NIMAGES
Number of images. The number of images checked is returned in the specified TAE INTEGER variable.
Subcommand -TK2:
Checks all images transferred from University of Tokyo. Images with the correct file size are moved to the ADAPSACQ directory (See User Note 6).

INDIR(/SGS4/KM1/XFER/UTOKYO)
Input directory. Directory where the images to be checked are located.

NIMAGES
Number of images. The number of images checked is returned in the specified TAE INTEGER variable.
Subcommand -UMX:
Checks all images transferred from University of Mexico. Images with the correct file size are moved to the ADAPSACQ directory (See User Note 6).

INDIR(/SGS4/KM1/XFER/UMX)
Input directory. Directory where the images to be checked are located.

NIMAGES
Number of images. The number of images checked is returned in the specified TAE INTEGER variable.
Subcommand -NSIDC:
Checks all images transferred from National Snow and Ice Data Center (NSIDC). Valid images are moved to the ADAPSING directory (See User Note 9).

INDIR(/SGS4/KM1/XFER/NSIDC)
Input directory. Directory where the images to be checked are located.

NIMAGES
Number of images. The number of images checked is returned in the specified TAE INTEGER variable.
Subcommand -OPF:
Checks all images transferred from Oberpfaffenhofen Germany. Images with the correct file size are moved to the ADAPSACQ directory (See User Note 6).

INDIR(/SGS4/KM1/XFER/OPF)
Input directory. Directory where the images to be checked are located.

NIMAGES
Number of images. The number of images checked is returned in the specified TAE INTEGER variable.
Subcommand -PAS:
Checks all images transferred from Prince Albert, Canada. Images with the correct file size are moved to the ADAPSACQ directory (See User Note 6).

INDIR(/AVHRR/ADAPS/XFER/PAS)
Input directory. Directory where the images to be checked are located.

NIMAGES
Number of images. The number of images checked is returned in the specified TAE INTEGER variable.

Examples:

  1. LAS> cktrans-baa nimages=numb

    CKTRANS will search INDIR for images matching the BAA naming scheme (see User Note 1) and check them for the Miami image format (see User Note 7). Images in the Miami format are moved into the ADAPSACQ directory and others are moved to ADAPSERR and must be retransferred. The number of images that are checked is returned in the TAE INTEGER variable NUMB.

  2. LAS> cktrans-lsu nimages=numb

    CKTRANS will search INDIR for images matching the LSU naming scheme (see User Note 2). All images matching the naming scheme will have a check sum computed and compared to the value in its associated check sum file (same root file name with a ".sum" extension). If the values are equal, the image is moved into the ADAPSACQ directory; otherwise, the image is moved to ADAPSERR and must be retransferred. The number of images that are checked is returned in the TAE INTEGER variable NUMB.

  3. LAS> cktrans-tk2 nimages=numb

    CKTRANS will search INDIR for images matching the TK2 naming scheme (see User Note 3). All images matching the naming scheme are checked to confirm that they were transferred completely (they are the same size as they were in Tokyo -> the size is in a corresponding file with the .done extension), If the files were transferred correctly they are moved to the ADAPSACQ directory; otherwise they are moved to ADAPSERR and must be retransferred. The number of images that are checked is returned in the TAE INTEGER variable NUMB.

  4. LAS> cktrans-nsidc nimages=numb

    CKTRANS will search INDIR for images matching the NSIDC naming scheme (see User Note 4). All images matching the naming scheme are checked to confirm that they are in the required AVHRR archive format. Images in the AVHRR archive format are moved into the ADAPSING directory, and others are moved to ADAPSERR and must be retransferred. The number of images that are checked is returned in the TAE INTEGER variable NUMB.

  5. LAS> cktrans-umx nimages=numb

    CKTRANS will search INDIR for images matching the UMX naming scheme (see User Note 5). All images matching the naming scheme are checked to confirm that they were transferred completely (they are the same size as they were in Mexico -> the size is in a corresponding file with the .done extension), If the files were transferred correctly they are moved to the ADAPSACQ directory; otherwise they are moved to ADAPSERR and must be retransferred. The number of images that are checked is returned in the TAE INTEGER variable NUMB.

  6. LAS> cktrans-opf nimages=numb

    CKTRANS will search INDIR for images matching the OPF naming scheme (see User Note 12). All images matching the naming scheme are checked to confirm that they were transferred completely i.e. we have received a file with extension .done and that they are the same size indicated in the .done file. If the files were transferred correctly they are moved to the ADAPSACQ directory; otherwise they are moved to ADAPSERR and must be retransferred. The number of images that are checked is returned in the TAE INTEGER variable NUMB.

Description/Algorithm:

CKTRANS has a subcommand for each receiving station that transfers images over the network to the EROS Data Center. Depending upon the receiving station, CKTRANS will verify the images have been successfully transferred. To determine if an image was successfully transferred, a check sum is computed for the image on the current system and is compared to the check sum value computed on the system it was transferred from. If the values are equal, the image was transferred successfully (see User Note 6).

Images that have been successfully transferred are moved into the ADAPSACQ or ADAPSING directory for processing (see User Notes 7 and 8). All other images are moved to ADAPSERR. The log file "CKTRANS;LOG" in the ADAPSLOG directory should be checked for any error messages.

Nonfatal Error Messages:

  1. [cknsidc-ceos] Unexpected CEOS ID found: <xxx>

    CEOS ID <xxx> is not one of the IDs expected from NSIDC. If the ID is a valid ID contact the system administrator.

  2. [cktrans-disk] Not enough room in ADAPSACQ (<xxxxx> bytes)

    There is not enough room in the ADAPSACQ directory to move images into it for processing. Run CKTRANS again when there are at least <xxxxx> bytes available in this directory.

  3. [cktrans-exists] Image <xxxxx> could not be renamed to <yyyyy>

    The transferred image <xxxxx> could not be renamed to <yyyyy> because an image by this name already exists. This image should be manually renamed to an appropriate name. See User Note 6.

  4. [cknsidc-hdr] Error reading header for <xxxxx>

    An error was encountered while reading the header file for the specified image. Verify the header file for this image is a valid AVHRR archive header.

  5. [ckbaa-hdr] Invalid header found in <xxxxx>

    The Miami header for the specified image does not contain the required values. Consult the system administrator to examine these fields. This image may have to be retransferred.

  6. [cktrans-move] Error moving <xxxxx> to ADAPSACQ

    The specified image could not be moved to ADAPSACQ. Verify the file and directory permissions are set appropriately and there is enough disk space available.

  7. [cknsidc-size] File size not multiple of <xxxxx> for <yyyyy>

    The number of bytes contained in the image <yyyyy> is not a multiple of <xxxxx>. This image should be retransferred from NSIDC.

  8. [cklsu-sum] No check sum file for <xxxxx>

    No check sum file exists for image <xxxxx>. LSU must retransfer the check sum file for this image.

  9. [ckutokyo-unequal] File sizes differ for <xxxxx>. Local size = <yyyyy>, remote size = <zzzzz>.

    The size of transferred file is not the same as it was before it was transferred. The image must be retransmitted.

  10. [cklsu-unequal] Check sums do not agree for <xxxxx>. Local sum = <yyyyy>, remote sum = <zzzzz>

    The check sums for image <xxxxx> are not equal. This image must be retransferred from LSU.

  11. [cklsu-year] Unknown year. Setting it to <xx>

    The year could not be extracted from the image name. The year will be set to the current year.

  12. [ckumx-unequal] File sizes differ for <xxxxx>. Local size = <yyyyy>, remote size = <zzzzz>.

    The size of transferred file is not the same as it was before it was transferred. The image must be retransmitted.

Fatal Error Messages:

  1. [cktrans-abort] User aborted <xxxxx>

    The user aborted the specified function.

  2. [cktrans-args] Must have <xxxxx> arguments for <yyyyy>

    The command <yyyyy> was called with an inappropriate number of arguments. Consult the system administrator.

  3. [cktrans-dir] Error accessing INDIR

    CKTRANS was unable to access INDIR. Check the permissions on this directory and rerun.

  4. [cktrans-env] <xxxxx> and <yyyyy> are not set

    The specified environment variables must be set. Set these variables to the appropriate values and run CKTRANS again.

  5. [cktrans-fatal] Fatal error encountered

    A fatal error was encountered. The message displayed immediately preceding this message is the error encountered.

  6. [cktrans-lib] Error determining library for <xxxxx>

    CKTRANS could not find the path for the specified command. Ensure the path for this command is in one of the TAE global variables $USERLIB, $APLIB, or $SYSLIB and that all of the environment variables referenced in these paths are set appropriately.

User Notes:

  1. The naming scheme for images transferred from the BAA receiving station is <YYJJJHHMMSS>.n<XX> where YY is the two digit year in which the image was acquired, JJJ is the Julian day of acquisition, HH, MM, and SS are the hour, minute, and second at the start of the acquisition, and XX is the number of the satellite that acquired the image.

  2. The naming scheme for images transferred from the LSU receiving station is n<SS>.<YYMMDD>.<HHMM>.acq where SS is the number of the satellite that acquired the image, YY, MM, and DD are the year, month, and day of acquisition, and HHMM is the hour and minute at the start of the acquisition.

  3. The naming scheme for images transferred from TK2 is a<T><NN><MMDDYY><HHMMSS>.tk2 where: T is the data type (l for LAC, g for GAC, h for HRPT), NN is the satellite number, MMDDYY is the date of acquisition (month, day and year), and HHMMSS is the starting time of acquisition (hour, minute, second).

  4. The naming scheme for images transferred from NSIDC is a<SS>_<XXX>_<YYMMDD>_<HHMM>.arch where SS is the satellite number, XXX is their three character abbreviation for the receiving station which acquired the data, YYMMDD is the year, month, and day of acquisition, and HHMM is the hour and minute at the start of acquisition.

  5. The naming scheme for images transferred from UMX is n<SS>.<YYMMDD>.<HHMM>.mx.lac where SS is the satellite number, YYMMDD is the year, month, and day of acquisition, and HHMM is the hour and minute at the start of acquisition.

  6. A check sum is a value computed using the byte values within a file and a common algorithm. When an image is transferred across the network for the Global 1KM project, a check sum value is computed before and after the transfer. If the check sum value on the destination machine is equal to the value on the source machine, the image was transferred successfully. If an error occurred during the transfer, some of the bytes will not be received correctly and the check sum values will not agree. For more details see the UNIX command "sum".

  7. Reference for Miami format:

    Nimbus/Tiros Archive Disk Format, University of Miami, RSMAS/MPO, James W. Brown, 14-Apr-1992.

  8. When an image is moved into the ADAPSACQ directory for processing, it is renamed to a standard name such as akm_<XXX>_<YY>_fn<ZZZ>.<XXX>. Here, XXX is the three character CEOS ID of the receiving station that supplied the image, YY is the two digit year in which the image was acquired, and ZZZ is the number of images received from the station to date. When ZZZ reaches 999 it is reset to 001.

  9. Images transferred from NSIDC are in the EROS Data Center's AVHRR archive format. These images are checked to confirm the size of the image matches the number of lines specified in the header file and the CEOS ID is converted from their designation to the internationally approved ID.

    Images that are in the EROS Data Center's AVHRR archive format are moved directly into the ADAPSING directory for processing.

  10. During normal processing, CKTRANS will be called every two hours. When an error is encountered with an image it is moved to the ADAPSERR directory. This prevents CKTRANS from reporting the same error multiple times. It is up to the user to look at the "CKTRANS;LOG" file in the ADAPSLOG directory to determine the appropriate action.

  11. A related function is IMGTRANS.

  12. Reference for Germany format:

    The naming scheme for images transferred from the Germany receiving station is <XXNSSYYMMDDHHmm.hrpt.Z or .gz> where XX is the station -- OP for Oberpfaffenhofen Germany or TF for O'Higgins Antarctica; SS is the satellite that acquired the image; YYMMDDHHmm are the year, month, day, hour and minute of acquisition; and an extension of .Z for Unix compression or .gz for gzip compression.

  13. Reference for Prince Albert format:

    The naming scheme for images transferred from Prince Albert Canada receiving station is <noaa_SS_YYYYMMDD_HHmm_OOOOO.zip> where SS is the satellite that acquiredthe image; YYYYMMDD is the year month and day; HHmm is hour and minute at start of acquisition; and OOOOO is the orbit number. The image is compressed and, when unzipped, contains several files including: thumbnail images with .jpg extension; a header with .led extension; a trailer with .trl extension; misc. files with .nul and .vol extensions; and the image data file with .img extension. The header and image are concatenated together to form the PAS image file expected by INGEST.