Since Optimized LAS is new on the market people are obviously interested in different ways it compares to other solutions. Optimized LAS has a number of benefits in terms of providing compression, spatial indexing and statistics required for better user experiences as well as restructuring for use in cloud based storage and distribution. Other solutions may do things differently and it can be hard to make fair comparisons. In this post we’ll try to clarify how to do this from the LAS Optimizer’s perspective. First up, compression speed:
Apples-to-apples comparison of compression performance between LAS Optimizer and other software
Raw compression speed is one factor to look at when comparing the LAS Optimizer to other solutions. Most other software that compresses LAS does just that, compression and nothing else. Since the LAS Optimizer does a combination of things, to look at compression speed alone we need to exclude those other factors for a fair comparison. Here’s how you run the Optimizer at its fastest with it only performing the work of compression:
- Create a ‘*.lasx’ file for a LAS file. This sidecar auxiliary file contains statistics and indexes for the LAS file. You can get this made in one of two ways:
- Use the Optimizer itself to compress and decompress a file. The resulting LAS will have an additional *.lasx sitting next to it.
- Use the LAS dataset in ArcGIS 10.2. One of the options on the LAS Dataset Properties dialog is to Calculate Statistics. This will make a lasx for each referenced LAS file.
- Under the Optimizer’s Advanced Options make sure the CPU power is set to 100%.
- Turn off ‘Rearrange points’ and ‘Import PRJ file’ options.
- Run the Optimizer.
An alternative, if the other software has options to build indexes, sort point records, etc., is to include them in the process and the time it takes to execute them.