You’ve heard of Open Street Map, right? You can think of it as Wikipedia for maps: people from all over the world map their own neighborhoods, and the results are made available for free, to all, with no copyright restrictions. For most of the US the road network has been pretty well mapped already, via free data available from the government, but it can get out of date surprisingly quickly and of course it doesn’t list the really important stuff like where to get the best ice cream.

These brave souls are about to redefine the leisurely walk.

On March 13th, nineteen people from CUGOS (including three Lizards) and one dog met up over on sunny Bainbridge Island for an Open Street Map mapping party. It was a diverse group — academics, kids, hackers, spouses. We met in the morning at the Bainbridge ferry dock, took a picture to commemorate the event, and divided up into four groups. Each group then spent the next few hours walking around a different part of Bainbridge’s downtown core, recording the coordinates of any “features of interest”:

• roads that had changed or been renamed
• “street furniture”: bus stops, park benches, fire hydrants
• points of interest: pharmacies, libraries, museums, pubs, ice cream parlors
• walking trails
• and much, MUCH more

Holly reviews her route while Dane gets “walking orders” from Michael.

Altogether we collected a few hundred different way points, using everything from handheld GPS units to iPhones to laser range finders. Over a leisurely late lunch by the waterfront, and in a subsequent CUGOS meeting, we worked to get all our GPS tracks and waypoints uploaded to the OSM databases.

Leaving no avenue uncharted, no point of interest unheralded, Michael, Walter and Roger investigate.

A walk through Bainbridge on a sunny day with friends — and GPS gear. What more could a GIS geek want?

Roger and Tifani display the elements of their GPS walking kit (bus stop sold separately).

Photos courtesy of CUGOS’ own Roger and Tifani.

Several of us just returned from the ILMF 2010 conference in Denver, Colorado. What was near and dear to my heart there was the interest in LiDAR compression. Several presentations focused on this (linked items below are PDF documents):

• “Storing and Managing LiDAR Data” by Jon Skiffington (LizardTech)
• “Compressing LiDAR Waveform Data” by Dr. Charles Toth (Ohio State University)
• “laszip: Lossless Compression for LiDAR in LAS Format” (poster) by Dr Martin Isenburg (Lawrence Livermore National Laboratory)
• “LiDAR Compression with MrSID Generation 4” by Michael Rosen (LizardTech)

My sense from talking with the other presenters is that this is something for which the industry is hungry. Dr. Toth is researching ways to compress waveform data (as opposed to the spatial and other attributes of the point cloud itself). He presented two approaches:  one based on a wavelet transform and another based on compressive sensing.

Dr. Isenburg presented a poster session describing laszip, a compression mechanism for LAS files. He described it to me as being primarily focused on archiving LAS data and so rather orthogonal to our efforts, which emphasize accessibility and integration. Also, laszip is free.

Mr. Skiffington’s presentation focused on our LiDAR Compressor product while your author’s presentation gave an outline of the motivation for and an algorithmic explanation of the underlying MG4 technology.

I had several people asked for copies of my presentation so I’ve provided the link above.

Michael Rosen
LizardTech, Engineering Mgr
mrosen at lizardtech dot com