U.S. Department of the Interior U.S. Geological Survey

Jason Stoker Physical Scientist USGS EROS

Lidar data handling: why standards, specs and metadata unfortunately matter

The lidar spectrum

Primary Region of Interest (km2)

Density &

Accuracy (pts / m

2)

The airborne analogy

Stoker, J.M.; Tyler, D.J.; Turnipseed, D.P.; Van Wilson, K., Jr., and Oimoen, M.J., 2009. Integrating disparate lidar datasets for a regional storm tide inundation analysis of Hurricane Katrina. Journal of Coastal Research, SI(53), 66–72.

A real mess

The bottom line…….. •  For an individual:

• Metadata doesn’t matter* • Standards don’t matter* • Specifications don’t matter*

*If you don’t want to share your data with anyone else, want your data to have any usefulness outside of what you collected it for, or contribute 3-D snapshots in time to the greater scientific world

The argument against

•  Making properly formatted detailed metadata is a pain, time consuming, and has little value to me

•  Standards are boring

•  Specifications are constraining

•  Things are always changing anyway

•  My data is not geolocated

•  Why would anyone want my source TLS data anyway?

The argument against

95% of us in this room make a living proving that the “standard” way is not good enough Without a standard way to refute or improve, what will we publish?

Why they do matter •  Attempting multi-project analyses or multi-scale analyses is much easier if the data is consistent

•  Properly formatted metadata with well defined specifications and standardized procedures make collective data easily searchable, comparable and useable later

•  Easier to repeat measurements with proper metadata, standard procedures and consistent specifications = better change detection

•  Reduced/better understood variability between collections

Why they do matter

The world is bigger than you •  Your data could be the key to cure cancer, or to unlock the mysteries of the universe – if others can make any sense of it

•  If you used public funds to support the collection of the data, it isn’t just your proprietary data but the taxpayer’s data

My vision of the future of lidar

Where we are today

A few of my recommendations 1.  TLS, Mobile Mapping, Airborne and satellite lidar data

can’t easily talk to each other- we need to improve this

2.  TLS, Mobile Mapping, Airborne and satellite lidar people don’t talk to each other as much as we should- we need to improve this

(talking to yourself doesn’t count)

3.  The TLS community needs to develop an agreed-upon spatial metadata template that includes accuracy assesment and is coordinated with the other geospatial communities to make querying and reporting easy

4.  The TLS community should build upon the work that has been done by the other lidar communities, but retain the information that makes TLS data unique from other data

Final thoughts • While the TLS gives an individual a tremendous amount of power to render their personal world in 3-D, there are other worlds than these. Focus on your problem, but be mindful that there may be others.

• Don’t be afraid to share your data- you are an expert, we trust you did it right, or at least have enough confidence in it that you can tell us how it was done so we can repeat it

• The power of multiscale measurements has yet to reach its potential, because each scale is still treated individually

• Don’t let the vendors dictate standards and specs- their best interests may not be yours as a user

•  We are still at the infancy of these technologies- there is still time to do it right before people get too entrenched to change or adapt

THANK YOU