Reads LTWG full-scene formatted tapes.
Reads Landsat LTWG full-scene formatted tapes and creates a LAS image. The image on tape may be windowed or subbanded when copied. Ancillary files may also be written to disk.
- COMMENT
- Description of tape(s). A text string sent to the operator's terminal describing the tape(s) to be mounted. COMMENT should contain the tape library identification number and a short description of the tape. This will allow the operator to ensure the correct tape is mounted. See User Note 2.
- OUT
- Output image. The name of the output LAS image. The size of the output image is determined by information from the leader file on tape or the values specified in WINDOW and BANDS. The output data type is BYTE.
- WINDOW(--)
- Window specification. Specifies the starting line, starting sample, number of lines, and number of samples to be processed. The default indicates that the entire image will be processed. If the starting line and sample values are not 1, then they must be evenly divisible by four unless the entire image is to be processed. See User Note 5.
- BANDS(1,2,3,4,5,6,7)
- Band number(s). The image bands on tape to be processed. The default indicates that all bands present on tape are processed. See User Note 2.
- WRTDSK(LEAD)
- Write to disk. Specifies which associated files/or records are to be copied from tape. These files are associated with the output image with the specified extensions. Any combination of these files may be specified.
= VDF: Volume Directory file. The volume directory file is written to "<xxxxx>;vdf". = LEAD: Leader file. The leader file is written to "<xxxxx>;lead". = TRAI: Trailer file. The trailer file is written to "<xxxxx>;trai". See User Note 2. = SUPP: Supplemental file. The supplemental file is written to "<xxxxx>;supp". See User Note 2. = CAL: Calibration file. The calibration file is written to "<xxxxx>;cal". = WOR: Workorder summary file. The work order summary file is written to "<xxxxx>;wor". = HST: History file. The processing history file is written to "<xxxxx>;hst".
The tape bb0707 is mounted on a drive. The user has specified that a 1024x1024 window be copied from tape starting at line 100, sample 100. Only bands 2 and 4 will be copied to TAI.IMAGE. By default, the leader file will be copied to the disk. Because the trailer and supplemental files are not being copied, only those tapes that contain bands 2 and 4 (bb0707 and bb0705) need to be specified.
The volume directory file and the leader file are read to obtain necessary processing information, i.e, band format, record size, etc.. If requested, these files are written to the associated files ;vdf and ;lead, repectively.The image file descriptor record is then read to obtain image size, band count, data type, blocking factor, and the number of prefix and suffix bytes within each image line. If requested, this record is written to the associated file ;idr.
A LAS image is created and opened for output. For each line and band to be read, the image data is extracted from the physical tape record and written to disk. If specified, the image data suffix and prefix data for each image line is written to disk in the ";IDR" file.
Once all of the requested image data is read, the third tape is mounted if the trailer or supplemental files specified to be written to disk. These files will be associated with the output LAS image and will have the extensions ";TRAI",";SUPP",";CAL",";WOR" and ";HST".
The band entered in BANDS does not exist on tape. Processing will continue with the remaining bands being copied from tape.
The image did not contain map projection information. The corners of the image will approximated. See User Note 4.
A nonfatal error was encountered during processing. The error message displayed immediately preceding this message is the specific error encountered. Processing continues.
The tape did not contain projection information or the projection is not currently supported by LTWG2IN. The image will be created with an invalid DDR. Contact the system administrator.
The specified tape did not contain a supplemental file and WRTDSK specified that one should be written to disk. Processing continues.
The specified window is larger than the image data on tape. The window has been reset to be the intersection of the window specification and the actual image.
An error occurred allocating memory. Rerun, and if the error persists, contact the system administrator.
The next tape in the volume is needed to continue processing. Enter all the tape IDs of the tape set in sequential order in COMMENT and rerun.
The data type of the image data on tape is not currently handled by LTWG2IN. Only BTYE is currently handled. Contact the system administrator.
A fatal error was encountered during processing. The error message displayed preceding this message is the specific error encountered. Processing is terminated.
An error was encountered reading the tape. Verify that the tape is good and conforms to the LTWG2IN tape format.
An error was encountered skipping to the correct location on the tape. Verify that the tape is good and conforms to the LTWG tape format or rerun and specify a window.
An invalid window was specified. Starting line and sample specifications must be evenly divided by four, if specified. This windowing restriction is due to the need to expand the thermal band to match non-thermal bands. Respecify the window and re-run.
No bands specified in BANDS were available on the input tapes. Respecify BANDS and rerun.
The values of WINDOW must be greater than or equal to one. Respecify WINDOW and re-run.
Documents of the LANDSAT-D CCT Standards Committee Presented to the LANDSAT Ground Station Operators Working Group, Draft, August 15, 1978.
LANDSAT Technical Working Group, Format for the Thematic Mapper CCT, EOSAT, Version 1.4, March 1993.