laszip now compresses LAS 1.4 (via "compatibility mode")

[Martin Isenburg]

Hello,

The latest version laszip of LAStools (150330) compresses LAS 1.4 via "compatibility mode". This re-codes LAS 1.4 points as LAS 1.2 or LAS 1.3 points with extra bytes so that the resulting LAZ files are both (a) compressed LAS 1.4 content but also (b) readable with any older, existing, legacy software that can already read LAZ content. For sample use the below. The lasinfo reports of both, the uncompressed LAZ and the compressed LAZ are attached.

There are two limitations: (a) the LAS 1.4 files must have fewer that 4 billion points. and (b) the LAS 1.4 file must not use EVLRs. 

Remember ... the main reason we held off the development o a native LAS 1.4 compressor based on your input [1] was our hope that we could convince ESRI to join the LiDAR community and work with us to develop a joint compressor for LAS 1.4 that that also fulfills their needs [2]. But this "compatabiliy mode" - sponsored by NOAA - allows us to use compresssed LAS 1.4 files today with existing software and little workflow impact (until LAS 1.4 has wider adoption and LAS 1.4 software has matured).

Please test it!!!

Regards,

Martin

[1] http://rapidlasso.com/2014/01/21/call-for-input-on-compression-of-las-1-4

[2] http://rapidlasso.com/2014/04/01/esri-and-rapidlasso-develop-joint-lidar-compressor

[3] http://rapidlasso.com/2014/10/06/rapidlasso-announces-laszip-compatibility-mode-for-las-1-4

----------------------

laszip -version

LAStools (by mar...@rapidlasso.com) version 150330

----------------------

laszip -i Q680i\Q680i_las14.las -o Q680i_las14.laz

laszip -i Q680i_las14.laz

lasdiff -i Q680i\Q680i_las14.las -o Q680i_las14.las

checking 'Q680i\Q680i_las14.las' against 'Q680i_las14.las'

headers are identical.

raw points are identical.

files are identical. both have 874463 points. took 0.39 secs.

----------------------

laszip -i VQ580\VQ580_las14.las -o VQ580_las14.laz

laszip -i VQ580_las14.laz

lasdiff -i VQ580\VQ580_las14.las -o VQ580_las14.las

checking 'VQ580\VQ580_las14.las' against 'VQ580_las14.las'

headers are identical.

raw points are identical.

files are identical. both have 414174 points. took 0.14 secs.

----------------------

laszip -i VMX450\VMX450_las14.las -o VMX450_las14.laz

laszip -i VMX450_las14.laz

lasdiff -i VMX450\VMX450_las14.las -o VMX450_las14.las

checking 'VMX450\VMX450_las14.las' against 'VMX450_las14.las'

headers are identical.

raw points are identical.

files are identical. both have 3372476 points. took 1.393 secs.

---------------------

lasinfo -odix _info -otxt -i Q680i_las14.las

lasinfo -odix _laz_info -otxt -i Q680i_las14.laz

lasinfo -odix _info -otxt -i VQ580_las14.las

lasinfo -odix _laz_info -otxt -i VQ580_las14.laz

lasinfo -odix _info -otxt -i VMX450_las14.las

lasinfo -odix _laz_info -otxt -i VMX450_las14.laz

Regards.

Martin @rapidlasso

[Martin Isenburg]

Hello,

our friends at RIEGL have tested the LAS 1.4 compression support in the latest version of laszip (150406) across an array of example files and they did not find any problems. The log they send me is below. 

Regards,

Martin

D:\WORK\las_LAZ\LAS14>laszip -version

LAStools (by mar...@rapidlasso.com) version 150406

 

D:\WORK\las_LAZ\LAS14>laszip -i Q680i_Waveforms.las -o Q680i_Waveforms.laz

D:\WORK\las_LAZ\LAS14>laszip -i Q680i_Waveforms.laz -o Q680i_Waveforms_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i Q680i_Waveforms.las -i Q680i_Waveforms_decompressed.las

checking 'Q680i_Waveforms.las' against 'Q680i_Waveforms_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 718785 points. took 0259 secs.

 

D:\WORK\las_LAZ\LAS14>laszip -i Q1560_extrabytes_channel1.las -o Q1560_extrabytes_channel1.laz

D:\WORK\las_LAZ\LAS14>laszip -i Q1560_extrabytes_channel1.laz -o Q1560_extrabytes_channel1_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i Q1560_extrabytes_channel1.las -i Q1560_extrabytes_channel1_decompressed.las

checking 'Q1560_extrabytes_channel1.las' against 'Q1560_extrabytes_channel1_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 8941574 points. took 4.734 secs.

 

D:\WORK\las_LAZ\LAS14>laszip -i Q1560_extrabytes_channel2.las -o Q1560_extrabytes_channel2.laz

D:\WORK\las_LAZ\LAS14>laszip -i Q1560_extrabytes_channel2.laz -o Q1560_extrabytes_channel2_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i Q1560_extrabytes_channel2.las -i Q1560_extrabytes_channel2_decompressed.las

checking 'Q1560_extrabytes_channel2.las' against 'Q1560_extrabytes_channel2_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 8750081 points. took 4.438 secs.

 

D:\WORK\las_LAZ\LAS14>laszip -i Q1560_noextrabytes_channel1.las -o Q1560_noextrabytes_channel1.laz

D:\WORK\las_LAZ\LAS14>laszip -i Q1560_noextrabytes_channel1.laz -o Q1560_noextrabytes_channel1_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i Q1560_noextrabytes_channel1.las -i Q1560_noextrabytes_channel1_decompressed.las

checking 'Q1560_noextrabytes_channel1.las' against 'Q1560_noextrabytes_channel1_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 8941574 points. took 2.432 secs.

 

D:\WORK\las_LAZ\LAS14>laszip -i Q1560_noextrabytes_channel2.las -o Q1560_noextrabytes_channel2.laz

D:\WORK\las_LAZ\LAS14>laszip -i Q1560_noextrabytes_channel2.laz -o Q1560_noextrabytes_channel2_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i Q1560_noextrabytes_channel2.las -i Q1560_noextrabytes_channel2_decompressed.las

checking 'Q1560_noextrabytes_channel2.las' against 'Q1560_noextrabytes_channel2_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 8750081 points. took 2.365 secs.

 

D:\WORK\las_LAZ\LAS14>laszip -i VQ880G_extrabytes_channel1_0.las -o VQ880G_extrabytes_channel1_0.laz

D:\WORK\las_LAZ\LAS14>laszip -i VQ880G_extrabytes_channel1_0.laz -o VQ880G_extrabytes_channel1_0_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i VQ880G_extrabytes_channel1_0.las -i VQ880G_extrabytes_channel1_0_decompressed.las

checking 'VQ880G_extrabytes_channel1_0.las' against 'VQ880G_extrabytes_channel1_0_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 4830449 points. took 2.764 secs.

 

D:\WORK\las_LAZ\LAS14>laszip -i VQ880G_extrabytes_channel1_1.las -o VQ880G_extrabytes_channel1_1.laz

D:\WORK\las_LAZ\LAS14>laszip -i VQ880G_extrabytes_channel1_1.laz -o VQ880G_extrabytes_channel1_1_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i VQ880G_extrabytes_channel1_1.las -i VQ880G_extrabytes_channel1_1_decompressed.las

checking 'VQ880G_extrabytes_channel1_1.las' against 'VQ880G_extrabytes_channel1_1_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 4963677 points. took 2.528 secs.

 

D:\WORK\las_LAZ\LAS14>laszip -i VQ880G_noextrabytes_channel1_0.las -o VQ880G_noextrabytes_channel1_0.laz

D:\WORK\las_LAZ\LAS14>laszip -i VQ880G_noextrabytes_channel1_0.laz -o VQ880G_noextrabytes_channel1_0_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i VQ880G_noextrabytes_channel1_0.las -i VQ880G_noextrabytes_channel1_0_decompressed.las

checking 'VQ880G_noextrabytes_channel1_0.las' against 'VQ880G_noextrabytes_channel1_0_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 4830449 points. took 1.27 secs.

 

D:\WORK\las_LAZ\LAS14>laszip -i VQ880G_noextrabytes_channel1_1.las -o VQ880G_noextrabytes_channel1_1.laz

D:\WORK\las_LAZ\LAS14>laszip -i VQ880G_noextrabytes_channel1_1.laz -o VQ880G_noextrabytes_channel1_1_decompressed.las

D:\WORK\las_LAZ\LAS14>lasdiff -i VQ880G_noextrabytes_channel1_1.las -i VQ880G_noextrabytes_channel1_1_decompressed.las

checking 'VQ880G_noextrabytes_channel1_1.las' against 'VQ880G_noextrabytes_channel1_1_decompressed.las'

headers are identical.

raw points are identical.

files are identical. both have 4963677 points. took 1.762 secs.