libLAS FAQ

This page is dedicated to Frequently Asked Questions about libLAS library and ASPRS LAS Format Standard.

What software supports ASPRS LAS Format?

There is a number of geospatial software packages that support read/write of ASPRS LAS Format. Popular software is listed on the Software Wiki page.

How does ASPRS LAS Format handle endianness?

According to the LAS Format Standard, all data is stored in little-endian format. The implication is that on little-endian architectures multi-byte data of LAS file can be read (or write) directly and bytes reordering is not required. On big-endian machines, however, bytes of multi-byte data must reordered between big-endian and little-endian format.

Does libLAS support LAS 2.0?

Not at this time. We hope to support as much of 2.0 when the specification stabilizes and there are enough softwares and implementations out there to base the work on. The LAS 2.0 specification is a whole-scale rewrite of the LAS specification, and its implementation will be challenging within libLAS.

Does libLAS support LAS 1.2?

Not at this time. While it would be a significant amount of work, libLAS can be updated to support 1.2 without too much trouble. Submit a patch, or hire one of the devs to make it happen.

How can I remove points classified as ground from LAS files?

Use the las2las utility to generate a new file with the points removed:

las2las -i input.las -o output.las --eliminate_class 2

How can I get past the linking error when building svn trunk on OS X 10.4?

ld: multiple definitions of symbol ___divdi3
/usr/lib/gcc/powerpc-apple-darwin8/4.0.1/libgcc.a(_divdi3.o) private external definition of ___divdi3 in section (__TEXT,__text)
/usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libgcc_s.10.4.dylib(_divdi3_s.o) definition of ___divdi3
ld: multiple definitions of symbol ___udivdi3
/usr/lib/gcc/powerpc-apple-darwin8/4.0.1/libgcc.a(_udivdi3.o) private external definition of ___udivdi3 in section (__TEXT,__text)
/usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libgcc_s.10.4.dylib(_udivdi3_s.o) definition of ___udivdi3
ld: multiple definitions of symbol ___umoddi3
/usr/lib/gcc/powerpc-apple-darwin8/4.0.1/libgcc.a(_umoddi3.o) private external definition of ___umoddi3 in section (__TEXT,__text)
/usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libgcc_s.10.4.dylib(_umoddi3_s.o) definition of ___umoddi3
/usr/bin/libtool: internal link edit command failed

OS X 10.4's XCode has an extremely old automake/autoconf/libtool stack, and without upgrading those, you'll have to stick to building libLAS from releases.