User's Guide

LAS2ARC

Creates an Arc Grid coverage from a LAS image.

Function:

Creates an Arc Grid coverage from a LAS image. The input image data type may by BYTE, INTEGER*2 or INTEGER*4.

Parameters:

IN
Input image. The name of the LAS image to be converted.

OUTGRID
Output Arc Grid. Name of the Arc Grid directory or stack file. The name is limited by Arc to be no more than 9 characters in length and only contain lower case characters. For a single output band, the output Grid file and supporting projection and location data will be in the directory specified by OUTGRID. For multi-band output, each of the n bands will be in a separate directory, named OUTGRIDc1, OUTGRIDc2...OUTGRIDcN, with the names of these directories entered in a stack file, OUTGRID.stk. Host file naming conventions must be used.

DELFLG("YES")
Delete flag. Delete the intermediate processing files.
  =YES: Delete all intermediate processing files.
  =NO:  Do not delete intermediate processing files.
GRIDFLAG("YES")
Grid flag.
  =YES: Create Arc Grid coverage.
  =NO:  Do not create Arc Grid coverage.  This is usually
        done when using only the intermediate files such as
        the .BIL or .STX file.  Be sure to set DELFLG to "NO"
        when using this option.

Example:

LAS> las2arc in=ah11050192131852(1,1,1000,1000:1,3,4) outgrid=africa
Bands 1,3, and 4 for the specified 1000 by 1000 window of IN will be converted to an Arc Grid format. The three bands will be stored in directories africac1, africac2, and africac3. Other required files will be generated from the intermediate files africa.stx, africa.prj and africa.hdr. The intermediate files will be deleted from disk after processing is completed.

Description/Algorithm

LAS2ARC begins by determining if Arc has been initialized; if not, LAS2ARC terminates. Otherwise the windowing information provided is used in conjunction with the input image DDR to generate the Arc supporting header (.HDR) and projection (.PRJ) files.
TRANSLAS-OUT creates an intermediate image file in BIL format. The Arc program IMAGEGRID is then used to create the desired output grid from the temporary files. If an Arc license is not currently available, LAS2ARC exits with an advisory message.
After IMAGEGRID executes successfully, the temporary .prj file is copied to the Arc grid directory or directories. If only one band was output, the file is simply copied to <OUTGRID>/prj. For multi-band output, the stack file (<OUTGRID>.stk) is accessed, and the projection file copied to the directory for each grid. By default LAS2ARC deletes all intermediate files.

Nonfatal Error Messages:

[las2arc-badmaptbl] Mapping table corrupted
An internal table has been corrupted; therefore a projection (PRJ) file cannot be created. Contact the system administrator for assistance.
[las2arc-badutmzn] DDR projection parameter [0] for UTM gives invalid zone
The longitude value specified for the UTM projection was less than -180 degrees or greater than or equal to +180. Check for valid projection coefficients. A projection file will not be created.
[las2arc-illconv] Illegal conversion code for projection coefficient <NN> -- value not written to PRJ file
An internal table has become corrupted. Projection data may not be processed correctly. Contact the system administrator for assistance.
[las2arc-nonfatal] Projection file not written
An error was encountered while trying to write or create the ;PRJ file. No file was created. The absence of the ;PRJ file will not cause an error for the Arc module IMAGEGRID-IN.
[las2arc-noprj] Projection or datum/spheroid information not available
The data needed to create a complete projection file for Arc could not be extracted from the input image's DDR. Either the DDR projection fields were invalid, or the data they contained could not be used for the reason specified by the immediately preceding message. If the output Arc Grid does not contain projection information, it can still be processed by Arc, but cannot be converted to other projections or combined with other data sets in other projections unless the Arc module PROJECT is used to define the coverage projection.
[las2arc-nozone] Can not determine valid zone code for UTM projection
The input DDR specified a UTM projection but does not specify either the UTM zone or the latitude and longitude of a point within the image from which the UTM zone could be determined. A projection file cannot be created.
[las2arc-proj] Unsupported projection type
An unsupported projection type was found in the DDR. Refer to the current Geometric Registration Overview, Appendix E and/or the Arc Map Projections & Coordinate Management manual.
[las2arc-cornerpts] DDR corner points not valid. Arc grid will not contain projection information.
The image DDR corner points are not valid. The corner points are used to compute header (.HDR) file information.
[las2arc-pixelsz] DDR pixel size not valid. Arc grid will not contain projection information.
The image DDR projection distances (pixel size) are not valid. The projection distances are used to compute header (.HDR) file information.
[las2arc-datarc] Datum <xxx> not supported by Arc.
Please contact LAS developers.
[las2arc-datlas] Datum <xxx> not supported by LAS2ARC.
Please contact LAS developers.
[las2arc-spharc] Spheroid <xx> not supported by Arc.
Please contact LAS developers.

Fatal Error Messages:

[las2arc-arcnoset] Arc/Info not initialized -- exit LAS and setup Arc
Arc/Info has not been initialized. Exit LAS and run the required setups for Arc. Contact the Arc system administrator for assistance.
[las2arc-dtype] Invalid data type
The data type of the input image cannot be ingested by Arc IMAGEGRID; therefore, it will not be converted. Valid input data type may be BYTE, INTEGER*2 or INTEGER*4.
[las2arc-exist] <XXX> file already exists
The specified file already exists. Delete it or specify a new outfile name and re-run the program.
[las2arc-fatal] Fatal error encountered
A fatal error was encountered during processing. The message that is displayed immediately preceding this message is the specific error that was encountered.
[las2arc-open] Error opening <XXX>
An error occurred while trying to open the specified file. Check file and directory protections.
[las2arc-proc] Error processing <XXX>
An error occurred while processing the specified file. Check file protections and available disk space before re-running.
[las2arc-qout] Error passing variables to TAE
An error occurred while passing parameters to the TAE parameter block. Contact the system administrator for assistance.
[las2arc-write] Error writing to <XXX>
An error occurred while writing to the specified file. Check file and directory protections.
[arc2las-outext] Extension found on OUTGRID filename. Arc does not support file names with extensions
Please choose an OUTGRID filename without an extension.
[arc2las-outlen] OUTGRID filename must be less than 10 chars
Please choose an OUTGRID filename that is within the Arc limits of 1 to 9 characters in length (excluding directory path).
[arc2las-rot] Input image is rotated. Rotated images are not supported by Arc
Please unrotate the image or choose a different input image and try again.
[las2arc-upcase] OUTGRID name cannot contain upper case characters
Arc does not allow upper case characters in filenames. Please choose an OUTGRID filename without upper case characters.

User Notes:

The corner coordinate information is not required by IMAGEGRID; allowing for an unregistered image to be ingested by Arc.
IMAGEGRID may not generate statistics for the Arc Grid. The user may have to run Grid BUILDSTA to generate Grid statistics before using the grid coverage with other Arc modules.
Refer to the TRANSLAS user guide for additional error messages.
LAS2ARC may be run from the UNIX command line by using ULAS. ULAS is a function in $LASTOOLS.
```
    Example:
    % ulas las2arc "[dg5.devsys.release.images]us93(1,1,20,30)" "us93"  
```
Arc/Info is invoked by the command arc. It is assumed that the Arc setup script adds the appropriate directory to your $PATH environment variable.