NASA ROSES ACCESS Project Review

Science Data Systems for Satellite and Airborne LiDAR Data

23 February 2011

C. Meertens and J. McWhirter, UNAVCOS-J. S.Khalsa and T. Haran, NSIDC/CUC. Baru and C. Crosby, SDSC/UCSD

D. Harding and B. Blair, NASA/GSFC and M. Hofton, U. Maryland

ACCESS: Advancing Collaborative Connections for Earth System Science

Objective

Approach

Co-Is/Partners

Key Milestones

Advancing Collaborative Connections for Earth System ScienceACCESS

Science Data Systems for Satellite and Airborne LiDAR Data

PI: Charles Meertens, UNAVCO

TRLin=5 TRLcurrent=5

19 April 2010

• Provide an integrated system (NLAS) for web services-based access to distributed NASA airborne (LVIS) and satellite (ICESAT/GLAS) LiDAR data archives using OpenTopography technologies.

• Define enhanced quality control (QC) metrics and a standard data format to improve evaluation of data quality, data usability, and compatibility with commercial LiDAR software packages.

• Provide users access to point cloud and waveform LiDAR data, on-demand digital elevation models (DEMs) generation, and derivative products and visualizations.

• Collaborate to define an industry-based LiDAR data format for NASA LiDAR data; to define enhanced QC metrics; and to design web services.

• Develop NSIDC ICESAT/GLAS web service.• Develop UNAVCO/GSFC LVIS data repository system

and web service.• Provide integrated user access using OpenTopography

Portal.• Science partner testing of enhanced data and QC

products and portal access.

Portal provides user access to LiDAR point cloud, standard and on-demand digital elevation models

generation.

• Complete data format, QC, and web services definitions.

12/10• Implementation of Data Web Services.

04/11• Beta release of NLAS/OpenTopography Portal with connectivity to NSIDC and UNAVCO. 10/11 • Production release of NLAS Portal. 03/12

S-J. S.Khalsa, NSIDC/CU; C.Baru, SDSC/UCSD; D.Harding, B.Blair, NASA/GSFC; and M.Hofton, U.MD.

High Altitude AirborneLaser Vegetation Imaging System ( LVIS)

~500 thousand points/day600 km altitude70 m footprint

Terrestrial LiDAR Scanning

100-500 million points/daytripod1 cm footprint

Satellite - Icesat

Low Altitude Airborne Laser Scanning

500 million-1 billion/day0.5 km altitude20 cm footprint

LiDAR Data Platforms

5 million points/day10 km altitude10 m footprint

Distributed and Large Collections from a diverse set of LiDAR Platforms

NLAS Project Overview

• Provide an integrated system (NLAS) for web services-based access to distributed NASA airborne (LVIS) and satellite (ICESAT/GLAS) LiDAR data archives using OpenTopography technologies.

• Define enhanced quality control (QC) metrics and a standard data format to improve evaluation of data quality, data usability, and compatibility with commercial LiDAR software packages.

• Provide users access to point cloud and waveform LiDAR data, on-demand digital elevation models (DEMs) generation, and derivative products and visualizations.

Public Website(search for “NLAS Opentopography”)

Hosted at OpenTopography

Objectives of NLAS Project(NASA Laser Access System)

Project Collaborative Wiki(uses Google sites nlaswiki)

Project Partners

UNAVCO PI: Charles Meertens, Project managementSoftware Engineer: Jeff McWhirter, Web services, API, and UI development

San Diego Supercomputing Center, University of California, San DiegoCo-PI: Chaitan Baru, Project management support Science Specialist: Chris Crosby, Algorithm Development, Science EvaluationSoftware Engineers: Vishu Nandigam, Minh Phan

Web services, API, and UI development

National Snow and Ice Data Center, NSIDC, CUCo-PI: Siri Jodha Singh Khalsa, Project management support, ESDSWGSoftware Engineers: Terry Haran, Nitin Khanna

Web services, API, UI and Visualization development

Goddard Space Flight CenterCo-PI: David Harding and Collaborator: Bryan Blair

Define data format, QA/QC, generate new products, science evaluation

University of MarylandCollaborator: Michelle Hofton

Define data format, generate new products, science evaluation

Major Accomplishments

Major Accomplishments• AGU NLAS presentation and NASA booth demo with end-to-end proof of

concept for LVIS, ICESat GLAS, and TLS data

• Ingest of select LVIS and ICESAT/GLAS data sets into Open Topography portal

• Definition of initial new GLAS GLANL format and LVIS Comprehensive format

• NLAS/RAMADDA supports LVIS, LAS, GLAS and ASCII data formats as well as aggregations of those files

• Provisional support for new ICEBRIDGE data sets – ATM, MCORDS, PARIS

• OpenTopography federated web service query to NLAS/RAMADDA for remote data repository collection summary metadata using ATOM caster.

• Public OpenTopography website at http://www.opentopography.org/index.php/about/nlas (sample LVIS collections, LVIS point cloud, DEM service)

Major Milestones

Major Milestones• Complete data format, QC, and web services definitions. 12/10

Draft definitions• Final definitions will evolve in stages over next two quarters

Develop file conversion software for LVIS, GLAS 12/10Note major step to use NLAS/RAMADDA to provide common data

repository and richer web services for LVIS and GLASSample data sets ingested in OT; Presentations at 2010 AGU 04/11

• Implementation of Data Web Services. 04/11

Prototype Catalog of services (connectivity between UNAVCO/SDSC OT)• Full data service implementation at NSIDC, OT

• Beta release of NLAS/OpenTopography Portal with connectivity to NSIDC and UNAVCO. 10/11 • Production release of NLAS Portal. 03/12

Project Schedule Summary

Project Schedule Summary

• Prototyping of NLAS workflow from data repositories to OT samples for LVIS and GLAS: slightly ahead of schedule

• Expedited by decision to utilize RAMADDA framework for data repositories and universal, flexible data translation web service

• Definition of data formats and enhanced QC/QA: on schedule• Definition of full data web services API and implementation : behind

schedule• Processing of complete datasets into comprehensive formats: behind

schedule• Science partner utilization of NLAS services: slightly behind schedule• Publicizing NLAS project: ahead of schedule

NLAS System Overview

OpenTopography Currently:

• Provides users access to ten’s of billions of LiDAR point cloud measurements and in industry standard formats (e.g. ascii, LAS)

• Provides on-demand processing services to enable generation of digital elevation models (DEMs), derivative products and visualizations.

NLAS will provide:

• Web Services access to distributed archives using a downloadable data repository package (NLAS/RAMADDA)

• Integrated access to NLAS data via OpenTopography

• An extensible Java package for reading and writing various LiDAR formats

• Add full waveform access and enhanced quality control (QC) metrics for ICESat/GLAS and LVIS

USERS

OpenTopographyOpenTopography

LVIS

LVIS

ICESat/GLASICESat/GLAS

NLAS RAMADDANLAS RAMADDA

Open Topography

OpenTopography Search

• Map Interface• Metadata about Dataset• Access to download and processing interface

• Public website http://www.opentopography.org/index.php/about/nlas

OpenTopography is funded through the National Science Foundation

Open Topography – Data Access

Data Downloading and Processing

User specifies Download/Processing Parameters

1.) Select area from Map Interface 2.) Point Cloud - Select format (ASCII or LAS) 3.) DEM Generation -Select Gridding Method, parameters, and format

Open Topography - Results Page

OpenTopographyOn-demand Processing Products:

• Subset of point cloud data• Digital Elevation (DEM) Map•Visualization product and .kmz file if desired•DEM on browser embedded GoogleEarth

LVIS example in Sierra Nevada

Open Topography - GLAS LiDAR Examples

ICESat/GLAS example

• Subset area of interest (below left)• Download ASCII Lat, Long, Elev (X,Y,Z)

• Example of subsequent import into Excel and plot of shot number vs elevation (below right)

Beta Server at: http://ot-beta.sdsc.edu:8080/gridsphere/gridsphere?cid=datasets

OT query of NLAS/RAMADDA product catalog using web services with ATOM casting just completed (see beta server)

Open Topography - Other LiDAR Examples

Terrestrial Laser Scanning example (NSF OT Development)• Subset area of interest• Download options include: ASCII Point Cloud, DEM, Hillshade & Slope Products, kmz, and image• Note that UNAVCO will implement TLS into RAMADDA for NSF

NLAS Interoperability

NLAS/RAMADDA

Open Topography Visualization/Analysis Clients

NLAS Web Service

HTML Interface

NLAS Web Service

Interoperability with DataRepository Web Service

NLAS – ICESat/GLAS GLANL/QCQA

ICESat Consolidated and Enhanced Altimetry Data Structure

Consolidation of parameters from 8 GLA product files•Eliminating numerous redundant, invalid and unused parameters•Producing a single data record for each laser shot

Selection of subsets from full ICESat GLA product files•Currently ~160 unique parameters in products•NLAS/GLANL 100 parameters in “long” subset for advanced users•NLAS/GLANL 18 parameters in “short” subset for casual users

Definition of 25 additional derived parameters for improved ease of use

•e.g., Conversion of waveform-derived relative range offsets to elevations

Definition of 6 QA/QC parameters to guide selection of appropriate data •Source of return: Earth surface, cloud, noise, indeterminate•Cause when no geolocation result reported: no return detected, instrument anomaly•Non-nadir data acquired during spacecraft maneuver•Possible presence of forward scattering range delay•Qualitative range precision assessment from S/N and signal fitting residual•Data reliability: composite yes/no flag for 8 parameters effecting quality

NLAS/RAMADDA

RAMADDA Overview• Data repository framework developed at Unidata/UCAR

– Freely available Java based open source package– Extensible plugin architecture

• Basic content management functionality

NLAS/RAMADDA plugin to support LiDAR data services• LiDAR data ingest, metadata harvesting and publication• Services include:

– Map overview, time series and waveform displays– Spatial subset, decimation– Conversion to multiple data format:

original binary, LAS, ASCII CSV, …– Product generation - Image, hill shade image, KMZ

NLAS/RAMADDA (LVIS or GLAS – same

package) Open

Topography Portal

Web services

•Spatial queries•Subsetting

•Data Conversion•Product generation

Ingest

MetadataDatabase

Other Clients

Collection Query

Metadataharvesting

LVIS Data System

File store

LiDAR Tools

Data Request

ATOM Response

LAS, ASCII CSV, etc.

NLAS Data Repository – LVIS Example

NLAS/RAMMADA

Open Topography

Portal

Web services

•Spatial queries•Subsetting

•Data Conversion•Product generation

Ingest

MetadataDatabase

Other Clients

Collection Query

Metadataharvesting

ICESat/GLAS Data System

File store

LiDAR Tools

Data Request

ATOM Response

LAS, ASCII CSV, etc.

NLAS Data Repository – ICESat/GLAS Example

NLAS/LiDAR Tools

NLAS/LiDAR Tools

Stand-alone Extensible Java package for reading and writing various LiDAR formats (made available via SourceForge)– LAS– LVIS (including waveform)– ICESAT/GLAS products– Other Icebridge formats – ATM, MCORDS, PARIS– Terrestrial Laser Scanning formats – text, PTX– Transforms global XYZ to Lat, Long, Elevation– …

LiDAR Subset Form

Data Access direct from NLAS/RAMADDA(may run demo instead if time allows)

LiDAR Waveform Data

Transmit Pulse

Alternate Signal Start

Outer Canopy Relief

Canopy InflectionStandard Gaussian Fit

Within Canopy Light Extinction

Ground ReliefAlternate Signal End

Amplitude (volts)

1064 nm laser pulse footprint~ 70 m diameter spaced 175 m along profile

Full Waveform LiDAR Data

NLAS/RAMADDA Waveform Display

NLAS/RAMADDAWaveform Display

Project Metrics

Metrics Plan•Custom and web log statistics from OpenTopographyhttp://www.opentopography.org/index.php/about/pcmetrics

•NLAS/RAMADDA Repository implementation includes web service API logging•Web log analysis software will be used to parse and summarize information on service requests (e.g. Domain analysis such as IP address, unique visitors, volume of data transferred, number of points processed, jobs executed)•UNAVCO will aggregate repository statistics and will be responsible for upload to NASA metrics system•Additional impact and software reuse metrics separate from the web logs are planned•OT has guest user (no login) and login access that allows increased processing limits and a custom workspace (mylidarjobs). NLAS will determine login and services access requirements and apply to RAMADDA and OT. NLAS will also need to pass through user id or IP through web service API and will bring this up with broader ESDSWG.

Example2008 LVIS Sierra Nevada, CA:Dec 2010 9 jobs 23,341,301 pointsJan 2011 4 jobs 2,186,947 pointsFeb 2011 11 jobs 14,797,042 points

ESDSWG Participation

ESDSWG Participation

Siri Jodha Khalsa is the representative to the ESDSWG

Highlights:• Standards Process Group (SPG) activities

•Participation in monthly teleconferences•Service on two SPG Technical Working Groups evaluating proposed standards and reviewer on third.

• New Orleans meeting in October, 2010 (McWhirter also attended)• Incorporated Atom-based Service Cast output format into the NLAS web service implementation.

Feedback planned to ESDSWG:• Federated distributed search/processing from NLAS Repositories• Web service pass-through of user id/IP• Khalsa is tracking developments of a proposed US national lidar data encoding standard and will provide feedback to ESDSWG.

Status and Next Steps

Accomplishments• LiDAR data repository framework• NLAS/RAMADDA Data Repository• LiDAR Data translation software tool• End-to-end proof of concept

– LVIS, ICESat GLAS, TLS• New GLAS product

– GLANL containing enhanced QC

Some Next Steps• Define NLAS web service API

– Data and metadata discovery– Data service access

• Implement NLAS production servers for GLAS and LVIS data sets• Implement full wave form service into OpenTopography• Explore potential application of NLAS services to other data sets –

ATM, TLS, etc.

GSFC LVISAntarctic Glacier Scan