harmonizing geospatial metadata

Ryan E. Bowe, GISPHarmonizing Geospatial Metadata Standards

Picking your genre

Know your data

What metadata standard are you currently using?Where are you posting your data?

Simple

\__/ ROCK \__/

While ArcGIS 10.x has a tolerable Item Details (KISS) and FGDC interface, it cannot handle true

ISO 19115 metadata without serious customization, which may not be feasible in

some more tightly controlled scenarios.

Esri

Metadata format: Unknown

Three Accuracy Metadata Sections

• USGS LiDAR Base Specification 1.2• ldraccur

• ISO 19115• gmd:DQ_AbsoluteExternal

PositionalAccuracy

• FGDC CSDGM• Building block for USGS LiDAR Base

Specification 1.2• vertacc

FGDC CSDGM

• Data Quality (dataqual)– Positional Accuracy (posacc)

• Vertical Accuracy (vertacc)– Vertical Accuracy Report

(vertaccr)– Quantitative Vertical Accuracy

(qvertpa)» Vertical Accuracy Value

(vertaccv - real)» Vertical Accuracy Value

Explanation (vertacce - text)

Data Quality’s Vertical Accuracy Section

USGS LiDAR Base Spec 1.2

• In addition to the vertacc section from the CSDGM, each of the various templates have the possibility to add all, or part, of the LiDAR Accuracy (ldracc) section which contains– Required Element: Required NVA for the

Raw Point Cloud Data ldrchacc. If none is given, enter 0.

– Required Element: Calculated NVA for the Raw Point Cloud Data rawnva

– Required Element: Number of Check Points used to calculate Raw NVA rawnvan

– Optional Element: Calculated NVA for the Classified Point Cloud Data clsnva

– Optional Element: Number of Check Points used to calculate Classified NVA clsnvan

LiDAR Information’s LiDAR Accuracy Section

• The rest of the ldracc section– Optional Element: Calculated VVA of the

classified point cloud data clsvva– Optional Element: Number of Check Points

used to calculate Classified VVA clsvvan

• ALL VALUES ARE IN METERS• There are no units after the

values. Only values.

LiDAR Information’s LiDAR Accuracy Section (Part 2)

• Classified LAS– Abstract– Supplemental Information talks about who

collected the control– LiDAR Accuracy

• Raw NVA– Source Info– Processing Description

• Swath– Supplemental Information talks about who

collected the control– LiDAR Accuracy

• Raw NVA– Source Info– Processing Description

Samples with LiDAR Section

• DEM– Abstract– Supplemental Information

talks about required accuracy– Source Information– Process Description

Samples without LiDAR Section

• Intensity Image– Abstract– Source Information– Process Description

• Breaklines– Abstract– Source Information– Process Description

ISO 19115

The future?

Although there is a push to migrating from CSDGM to ISO, most places have a crosswalk to assist the transition.LiDAR Base Spec is not in this section, so how is the LiDAR Accuracy documented?

gmd:DQ_AbsoluteExternalPositionalAccuracy

DQ:QuantitativeResult

So How Do You Do That?Step-By-Step Metadata

• Pick your main standard/extension• Pick your secondary standard/extension• Learn both to make them functional (FIND TOOLS)• Use a crosswalk

Thank You!Please let me know if you have further questions.