GeoPackage SWG Overview

®

Sponsored by

GeoPackage Standards Working Group

98th OGC Technical CommitteeWashington, DC USA

08 March 2016

Copyright © 2016 Open Geospatial Consortium

OGC®

Agenda

• Introductions – JY (10 minutes)• GeoPackage 1.1 – JY (30 minutes)• GeoPackage Elevation Extension Interoperability

Experiment – Carl Reed (20 minutes)• NSG Profile – Roy Rathbun (15 minutes)• GeoPackage Compliance – Matt Sorenson (10

minutes)• Future Considerations – JY (10 minutes)• Implications for an OGC GeoPackage Symbology

Encoding Standard (Discussion Paper) – JY (10 minutes)


OGC®

Introductions and Roll Call

• Jeff Yutzler, Image Matters LLC (chair)• Thomas Nierynck, Luciad (vice chair)


OGC®

Patent Call

INTELLECTUAL PROPERTY RIGHTS POLICY of the Open Geospatial Consortium, Inc. as approved on 19 December 2008

Please be aware that this meeting is being held under the Intellectual Property Rights Policy adopted by OGC. If you do not have a copy of this policy, please see me (the meeting Chair) during this meeting. You may also view and download a copy of that policy at:

http://portal.opengeospatial.org/files/?artifact_id=32268

At this time, I would ask that anyone in attendance inform me if they are personally aware of any claims under any patent applications or issued patents that would be likely to be infringed by an implementation of the standard or other work product which is the subject of this meeting. You need not be the inventor of such patent or patent application in order to inform us of its existence, nor will you be held responsible for expressing a belief that turns out to be inaccurate.


OGC®

Tile Pyramids24 zoom levels

GeoPackage: Raster Maps, Images and Feature Data in One File

Raster Maps:Small – Large Scale

ImageryLow – High Resolution

Single File Sqlite Databasecontaining all data for direct-use on mobile platforms & handheld devices

FeatureData

OGC®

What is GeoPackage

• Open format for geospatial information– Vector geospatial features– Raster tile matrix sets (pyramids) of imagery and raster

maps at various scales– Extensions

• SQLite database schema– Table definitions– Integrity assertions– Format limitations– Content constraints


OGC®

geopackage.org

• Go here first!• Web version of specification• News, implementations, sample data, and FAQ• Hyperlinks for participants (quickest way to portal,

Wiki, etc.)


OGC®

GitHub Hosting

• https://github.com/opengeospatial/geopackage• We’re the first SWG to do as much as possible on GitHub

– Encourages public input– Provides more modern tools– Portal, Wiki, and email list still used to conduct SWG business and

to protect participants’ intellectual property• Issue Tracker

– https://github.com/opengeospatial/geopackage/issues• http://geopackage.org hosted by GH Pages

– Suggestions welcome– Pull requests too! See the gh-pages branch.


https://github.com/opengeospatial/geopackage

https://github.com/opengeospatial/geopackage

https://github.com/opengeospatial/geopackage/issues

https://github.com/opengeospatial/geopackage/issues

http://geopackage.org/

OGC®

Vector Tables

• Similar to other relational databases • Built on existing standards

– OGC Simple Features– Well-known Binary (WKB)

• Not subject to many of Shapefile’s limitations


OGC®

Raster Tile Matrix Sets (Pyramids) Raster Basemaps and Imagery available online from raster

tile servers (WMS, WMTS) and offline in GeoPackages

Raster Maps:Small – Large Scale

ImageryLow – High Resolution

Single Raster Tile Server w/ raster basemap & imagery data.

Tile Pyramid24 zoom levels

Geopackage w/Raster Tile Data

Tile Pyramid24 zoom levels

OGC Web Servicesto online clients/appsWMS, WMTS, WFS

OGC®

Brief History

• Foundations established prior to 2012– SQLite3 (sqlite.org) – SpatiaLite (https://www.gaia-gis.it/fossil/libspatialite/home)– MBTiles (https://github.com/mapbox/mbtiles-spec/blob/master/1.2/spec.md)

• 2012 – Concept initiated by USACE’s AGC/TEC and NGA at a hosted TEM with FOSS / commercial software developers– Started as Google Groups; moved to OGC due to need for standards

development structure and potential IPR concerns• Oct. 2012 – SWG charter established• 2013-present – OGC Web Services (OWS) Testbeds

– Phase 9 developed initial draft spec; others built prototype applications• Feb. 2014 – Encoding Standard (1.0) adopted by OGC

– Mandated as of DISR* 14-2• Early 2015 – Corrigendum (1.0.1) adopted by OGC


* Defense Information Systems Registry

OGC®

Benefits

• Supports sharing of raster and vector geospatial information in a single container

• Supports direct use– Avoid intermediate format translations (extract, transform, load)– SQLite is a true relational database with built-in indexing

• Platform independent, supporting multiple computing environments (hardware and operating system)– Local storage reduces power requirements and supports

disconnected/intermittent/limited connectivity– Conserves storage space by allowing multiple applications to

access the same data store


OGC®

Emerging Uses

• Mobile applications• Data dissemination, including but not limited to

foundation GEOINT• Not the solution for everything

– For simpler vector applications, GeoJSON may be plenty– In some enterprises an SQLite-based solution may be

inappropriate


OGC®

State of GeoPackage

• Emerging as an important geospatial standard• Faster adoption than other OGC standards:

– 16+ separate vendors listed on geopackage.org– Promptly added to the US Defense Information Systems

Registry (DISR)– Will it win #TheShapefileChallenge ?

• Areas for improvement:– Data distribution (we are not seeing as much

GeoPackage data in the wild as we could)– Implementation guidance (we could use more helpful

content on geopackage.org)


OGC®

GeoPackage Implementation Examples

• GDAL• Luciad Lightspeed, Mobile, and Fusion• QGIS• Esri ArcGIS (10.2.2 for vector, 10.3 for tiles)• NGA• SpatiaLite (4.2.0)• GeoServer• Compusult• GeoTools• US Army ERDC• Envitia MapLink• Terrago (GeoPDF)

OGC®

GeoPackage 1.1

• The SWG has developed a Technical Amendment to the GeoPackage Encoding Standard

“Where…an OGC Standard is used…but technical changes are needed, a deliverable may be proposed for amendment. An amendment alters and/or adds to an existing OGC standard [and results] in a new version number of the document. An amendment may consist of additional reference examples, use cases, schema changes, and other normative and informative content or clarifications.” (http://docs.opengeospatial.org/pol/05-020r20/05-020r20.html#125)• Technical Amendment – more than corrigenda, but

less than a completely new edition of the standard.Copyright © 2015 Open Geospatial Consortium

http://docs.opengeospatial.org/pol/05-020r20/05-020r20.html#125



OGC®

GeoPackage 1.1 (continued)

• Goal: Improve the standard (especially readability and interoperability) without harming existing implementations

• Requires:Release Notes (15-123r1 posted on Pending

Documents)SWG ApprovalOGC Architecture Board review and approval– IPR review period– TC Vote (at TC meeting or by e-vote)

• The plan is for the vote to occur this week.


OGC®

Review of Substantive Changes

• All work was done in GitHub (see geopackage.org)• #102 – Add REQ 45 to describe tile matrix width

and height to eliminate interoperability failure• #132 – Collapse all extensions under Annex F. for

improved readability• #137 – Add new extension for CRS WKT support

(OGC 12-063r5)• #147 – Demote metadata / schema to extensions• #130 – Fix casing of column names for Schema• #189 – Update Application ID to 1.1


OGC®

Requirement 45

• Interoperability issue discovered during GeoPackage Plugfest (2014-5)– Tile numbering was inconsistent between

implementations – some used “tight” bounds and others used “potential” bounds to allow sharing between tile sets

• We added the following:The width of a tile matrix (the difference between min_x and max_x in gpkg_tile_matrix_set) SHALL equal the product of matrix_width, tile_width, and pixel_x_size for that zoom level. Similarly, height of a tile matrix (the difference between min_y and max_y in gpkg_tile_matrix_set) SHALL equal the product of matrix_height, tile_height, and pixel_y_size for that zoom level.Copyright © 2015 Open Geospatial Consortium

This won.

OGC®

CRS WKT Support

• OGC recently adopted 12-063r5 to address shortcomings in previous documents

• We want to provide a migration path while not breaking existing implementations

• Solution: Create a new extension– Implementations that support this extension add a

column to gpkg_spatial_ref_sys called “definition_12_063”

– Implementations shall populate both this column and the original “definition” column

– In some cases, one or the other may be “undefined”


OGC®

Questions


OGC®

GPKG-EE IE


OGC®

NSG Profile


OGC®

GeoPackage Compliance


OGC®

Future Considerations

• Over the summer, we conducted an on-line survey to gauge interest in potential extensions.

• We asked about the following:– Symbology/Styling– Multi-Resolution Geometries– Routing– New Geometry Types– New Image Types– Point Clouds– UTFGrid– Synchronization– Coverages

© 2016 Open Geospatial Consortium 25

OGC®

Survey Results


OGC®

Testbed 12

• Testbed 12 is at least partially addressing some of our proposed topic areas– Symbology/Styling– Routing– Others?


OGC®

Testbed 12 Engineering Reports

• As an aside, the Testbed sponsors have requested that at least three GeoPackage-related Engineering Reports be produced– A082 GeoPackage Routing and Symbology– A083 GeoPackage Mobile Apps Integration– A085 GeoPackage Change Request Evaluations

• We will bring these to the SWG for review as per– https://portal.opengeospatial.org/files/?artifact_id=66923


https://portal.opengeospatial.org/files/?artifact_id=66923

https://portal.opengeospatial.org/files/?artifact_id=66923

OGC®

Implications for a Symbology Extension

• OGC 15-122r1 evaluated this topic and proposed the following next steps:– Discuss this proposal in the broader community (outside

the SWG itself) to reach a consensus on approach.– Prioritize the use cases and pursue design and

reference implementations of the viable use case(s).– Establish a separate working group, coordinating with

the GeoPackage SWG (composed of interested GeoPackage SWG members and other stakeholders)

– Analyze applicable informative references to apply towards defining a draft specification to address viable use cases identified.


OGC®

Motion

• The GeoPackage SWG recommends that OGC 15-122r1 be recommended to the Technical Committee for release as a Discussion Paper.– Motion: Jeff Yutzler– Second: ??? – Discussion?– Objection to Unanimous Consent?


OGC®

Multi-Resolution Geometries

• The SWG has determined that the best way to address this issue is through data modeling as opposed to a change to the standard– https://github.com/opengeospatial/geopackage/issues/77

• In response, we posted the following:– http://www.geopackage.org/modeling_guidelines.html


https://github.com/opengeospatial/geopackage/issues/77

https://github.com/opengeospatial/geopackage/issues/77

http://www.geopackage.org/modeling_guidelines.html



OGC®

New Geometry Types

• This capability is already available through two extensions:– GeoPackage Non-Linear Geometry Types (F.1)– User Defined Geometry Types Extension of

GeoPackageBinary Geometry Encoding• At this time we do not have clear guidance on using

these extensions– https://github.com/opengeospatial/geopackage/issues/173

• There is some concern that these extensions are unusable in their current form

• We are looking for volunteers


OGC®

Other Topic Areas Not Under Development

• New Image Types• Point Clouds – maybe ask the Point Cloud DWG?• UTFGrid• Synchronization• Coverages• These can all be handled through extensions…if

we have the will


OGC®

Making Good Extensions

• May be developed by the SWG or brought in from outside

• Must have:Clear Use CaseSound technical approach

– Must be compatible with clients that just implement the core

Commitment from critical mass of vendors (usually 3) to implement


GeoPackage SWG Overview

Engineering

Transcript of GeoPackage SWG Overview