Your -clip command is eliminating all of the points, and las2las is dumb about telling you this.
http://liblas.org/ticket/162 is a bug to clean this up, and it has been applied to the repository. Howard On Jan 11, 2010, at 8:48 PM, Peter Tittmann wrote: > Hello, > > I wonder if you discovered what was wrong in this scenario > (http://www.mail-archive.com/[email protected]/msg00202.html) . I > am attempting to and select first only first returns and subset using the > following: > > $ las2las -i ucd_03.las -first_only -clip 409849.040000 4534962.800000 > 409949.04 4535062.8 -o ucd_03_fr.las > > and get a similar error message: > > clipped: 5135796 > Not able to fetch a point. LASReaderH is invalid: Pointer 'hPoint' is NULL in > 'LASPoint_Destroy'. (3) from method LASPoint_Destroy > > lasinfo on the created file returns: > > --------------------------------------------------------- > Header Summary > --------------------------------------------------------- > File Name: ucd_03_fr_s.las > Version: 1.2 > Source ID: 0 > Reserved: 0 > Project ID/GUID: '00000000-0000-0000-0000-000000000000' > System Identifier: 'MODIFICATION' > Generating Software: 'TerraScan' > File Creation Day/Year: 0/0 > Header Size 227 > Offset to Point Data 229 > Number Var. Length Records 0 > Point Data Format 1 > Point Data Record Length 28 > Number of Point Records 0 > Number of Points by Return 0 0 0 0 0 > Scale Factor X Y Z 0.01 0.01 0.01 > Offset X Y Z -0.000000 -0.000000 -0.000000 > Min X Y Z 409849.040000 4534962.810000 73.570000 > Max X Y Z 410860.310000 4535963.860000 239.200000 > Spatial Reference > > and > $ cat ucd_03_fr_s.las > returns > LASFMODIFICATIONTerraScan�� {�G�z�?{�G�z�?{�G�z�?���ףp=�A���(�Aq= > ��MQA> > ׳�lqagffff�...@�g�zdr@ > > Im suspicious that it might be that there is no spatial reference defined so > I'm working on how to define one but wanted to ask in case om off track. > > Thanks very much! > > PT > _______________________________________________ > Liblas-devel mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/liblas-devel _______________________________________________ Liblas-devel mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/liblas-devel
