Problem loading GeoTiff of odd bit depth

RossOverstreet

Hi Guys,

Global Mapper v11.01 Build Nov 6th keeps crashing and exiting every time I try to open some odd GeoTiffs. Based on error codes from other software, I believe the bit depth being used in these GeoTiffs is non-standard. Photoshop CS3 will not open them and complains of the bit depth. Manifold and Irfanview open it with a black image.

The GeoTiff is sidescan data from Anacapa Island in California.

Here's the source data:
http://coastalmap.marine.usgs.gov/regional/contusa/westcoast/socal/cinms/data.html

Click "Sidescan Imagery", download sana1m.tgz

Any ideas? Is the data corrupt?

This is not a big deal for me and certainly isn't time critical but it would be neat to be able to open the image.

Thanks,
Ross Overstreet

STH

I downloaded the file - this is the information in the header:

Output from Display Header
File Name: C:\temp\sana1m\sana1m\sana1m.tif
File Information:
Standard : : TIFF File
Format : : Word integers (16 bits)
Pixels per Line : 11574
Number of Lines : 4852
Samples per pixel : 1
File bits per sample : 16
Actual bits per sample : 16
Untiled file
Number of overviews : 0
Scanning device resolution : 1 : lines/inch
Orientation : 4 : Row major order, origin at top left
NO scan line headers : non-scannable file
Standard color table - type: 2
Color Table Size - Num entries: 65536
Packet size (16-bit words) : 0
Free vlt space (16-bit words) : 2000000000
Free packet space (16-bit words) : 2000000000
Raster to UOR matrix:
Unspecified or All Zero Matrix
Raster to World Matrix:
Units: Meters
amx[ 0]= 0.999961443, amx[ 1]= 0, amx[ 2]= 827296.451
amx[ 3]= 0, amx[ 4]= -0.999961443, amx[ 5]= 3770912.07
827296.451 , 3770912.07
838870.004741282 , 3770912.07
838870.004741282 , 3766060.25707856
827296.451 , 3766060.25707856
Geotiff_Information:
Version: 1
Key_Revision: 1.0
Tagged_Information:
ModelTiepointTag (2,3):
0 0 0
827296.451 3770912.07 0
ModelPixelScaleTag (1,3):
0.999961443 0.999961443 0
End_Of_Tags.
Keyed_Information:
GTModelTypeGeoKey (Short,1): ModelTypeProjected
GTRasterTypeGeoKey (Short,1): RasterPixelIsArea
GTCitationGeoKey (Ascii,235): "IMAGINE GeoTIFF Support\nCopyright 1991 - 2001 by ERDAS, Inc. All Rights Reserved\n@(#)$RCSfile: egtf.c $ $Revision: 1.9.2.9 $ $Date: 2002/10/28 15:14:13EST $\nProjection Name = NAD_1983_UTM_Zone_10N\nUnits = meters\nGeoTIFF Units = meters"
ProjectedCSTypeGeoKey (Short,1): PCS_NAD83_UTM_zone_10N
PCSCitationGeoKey (Ascii,205): "IMAGINE GeoTIFF Support\nCopyright 1991 - 2001 by ERDAS, Inc. All Rights Reserved\n@(#)$RCSfile: egtf.c $ $Revision: 1.9.2.9 $ $Date: 2002/10/28 15:14:13EST $\nUTM Zone 10N\nEllipsoid = GRS 1980\nDatum = NAD83"
ProjLinearUnitsGeoKey (Short,1): Linear_Meter
End_Of_Keys.
End_Of_Geotiff.
PCS = 26910 (NAD83 / UTM zone 10N)
Projection = 16010 (UTM zone 10N)
Projection Method: CT_TransverseMercator
ProjNatOriginLatGeoKey: 0.000000 ( 0d 0' 0.00"N)
ProjNatOriginLongGeoKey: -123.000000 (123d 0' 0.00"W)
ProjScaleAtNatOriginGeoKey: 0.999600
ProjFalseEastingGeoKey: 500000.000000 m
ProjFalseNorthingGeoKey: 0.000000 m
GCS: 4269/NAD83
Datum: 6269/North American Datum 1983
Ellipsoid: 7019/GRS 1980 (6378137.00,6356752.31)
Prime Meridian: 8901/Greenwich (0.000000/ 0d 0' 0.00"E)
Projection Linear Units: 9001/metre (1.000000m)
Corner Coordinates:
Upper Left ( 827296.451, 3770912.070)
Lower Left ( 827296.451, 3766060.257)
Upper Right ( 838870.005, 3770912.070)
Lower Right ( 838870.005, 3766060.257)
Center ( 833083.228, 3768486.164)

Attached is a screenshot of the file when opened in RasView and in ER Viewer - not sure if the colors should look like this or not? Anyway - it shows "corrupted" in both these viewers - less corrupt in ER Viewer.

global_mapper

Ross,

The problem was that the image is a 16-bit image, but uses a palette. I guess this is technically legal, but I've never seen this done. In any case, I've added support for reading this image and now it comes in correctly. I have placed a new build at http://www.globalmapper.com/global_mapper11.zip with the change for you to try. Simply download that file and extract the contents into your existing v11.xx installation folder to give it a try. If you are using the 64-bit version, there is a new build available at http://www.globalmapper.com/global_mapper11_64bit.zip .

Let me know if I can be of further assistance.

Thanks,

Mike
Global Mapper Support
support@globalmapper.com

RossOverstreet

Mike,

Thanks for fixing this for me! It works great now.

Your tech support is best I've ever seen and GM is the best money I've spent on software period. I post the problem here late at night and there's a fix before the start of the day. Amazing!

Thanks,
Ross Overstreet