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GeoTrellis

CI Join the chat at https://gitter.im/geotrellis/geotrellis ReadTheDocs Changelog Contributing

Maven Central Snapshots

GeoTrellis is a Scala library and framework that provides APIs for reading, writing and operating on geospatial raster and vector data. GeoTrellis also provides helpers for these same operations in Spark and for performing MapAlgebra operations on rasters. It is released under the Apache 2 License.

Please visit the project site for more information as well as some interactive demos.

You're also welcome to ask questions and talk to developers (let us know what you're working on!) via Gitter.

Getting Started

GeoTrellis is currently available for Scala 2.12 and 2.13, using Spark 3.3.x.

To get started with SBT, simply add the following to your build.sbt file:

libraryDependencies += "org.locationtech.geotrellis" %% "geotrellis-raster" % "<latest version>"

To grab the latest SNAPSHOT, RC or milestone build, add these resolvers:

// maven central snapshots
resolvers ++= Seq(
  "sonatype-snapshot" at "https://oss.sonatype.org/content/repositories/snapshots/"
)

// or eclipse snapshots
resolvers ++= Seq(
  "eclipse-releases" at "https://repo.eclipse.org/content/groups/releases",
  "eclipse-snapshots" at "https://repo.eclipse.org/content/groups/snapshots"
)

If you are just getting started with GeoTrellis, we recommend familiarizing yourself with the geotrellis-raster package, but it is just one of the many available. The complete list of published GeoTrellis packages includes:

  • geotrellis-accumulo: Accumulo store integration for GeoTrellis
  • geotrellis-accumulo-spark: Accumulo store integration for GeoTrellis + Spark
  • geotrellis-cassandra: Cassandra store integration for GeoTrellis
  • geotrellis-cassandra-spark: Cassandra store integration for GeoTrellis + Spark
  • geotrellis-gdal: GDAL bindings for GeoTrellis
  • geotrellis-geotools: Conversions to and from GeoTools Vector and Raster data
  • geotrellis-hbase: HBase store integration for GeoTrellis
  • geotrellis-hbase-spark: HBase store integration for GeoTrellis + Spark
  • geotrellis-layer: Datatypes to describe sets of rasters
  • geotrellis-macros: Performance optimizations for GeoTrellis operations
  • geotrellis-proj4: Coordinate Reference systems and reproject (Scala wrapper around Proj4j)
  • geotrellis-raster: Raster data types and operations, including MapAlgebra
  • geotrellis-raster-testkit: Testkit for testing geotrellis-raster types
  • geotrellis-s3: Amazon S3 store integration for GeoTrellis
  • geotrellis-s3-spark: Amazon S3 store integration for GeoTrellis + Spark
  • geotrellis-shapefile: Read ESRI Shapefiles into GeoTrellis data types via GeoTools
  • geotrellis-spark: Geospatially enables Spark and provides primitives for external data stores
  • geotrellis-spark-pipeline: DSL for geospatial ingest jobs using GeoTrellis + Spark
  • geotrellis-spark-testkit: Testkit for testing geotrellis-spark code
  • geotrellis-store: Abstract interfaces for storage services, with concrete implementations for local and Hadoop filesystems
  • geotrellis-util: Miscellaneous GeoTrellis helpers
  • geotrellis-vector: Vector data types and operations extending JTS
  • geotrellis-vector-testkit: Testkit for testing geotrellis-vector types
  • geotrellis-vectortile: Experimental vector tile support, including reading and writing

A more complete feature list can be found on the Module Hierarchy page of the GeoTrellis documentation. If you're looking for a specific feature or operation, we suggest searching there or reaching out on Gitter.

For older releases, check the complete list of packages and versions available at locationtech-releases.

Hello Raster

scala> import geotrellis.raster._
import geotrellis.raster._

scala> import geotrellis.raster.render.ascii._
import geotrellis.raster.render.ascii._

scala> import geotrellis.raster.mapalgebra.focal._
import geotrellis.raster.mapalgebra.focal._

scala> val nd = NODATA
nd: Int = -2147483648

scala> val input = Array[Int](
     nd, 7, 1, 1,  3, 5, 9, 8, 2,
      9, 1, 1, 2,  2, 2, 4, 3, 5,
      3, 8, 1, 3,  3, 3, 1, 2, 2,
      2, 4, 7, 1, nd, 1, 8, 4, 3)
input: Array[Int] = Array(-2147483648, 7, 1, 1, 3, 5, 9, 8, 2, 9, 1, 1, 2,
2, 2, 4, 3, 5, 3, 8, 1, 3, 3, 3, 1, 2, 2, 2, 4, 7, 1, -2147483648, 1, 8, 4, 3)

scala> val iat = IntArrayTile(input, 9, 4)  // 9 and 4 here specify columns and rows
iat: geotrellis.raster.IntArrayTile = IntArrayTile([I@278434d0,9,4)

// The renderAscii method is mostly useful when you're working with small tiles
// which can be taken in at a glance.
scala> iat.renderAscii(AsciiArtEncoder.Palette.STIPLED)
res0: String =
∘█  ▚▜██▖
█  ▖▖▖▜▚▜
▚█ ▚▚▚ ▖▖
▖▜█ ∘ █▜▚

scala> val focalNeighborhood = Square(1)  // a 3x3 square neighborhood
focalNeighborhood: geotrellis.raster.op.focal.Square =
 O  O  O
 O  O  O
 O  O  O

scala> val meanTile = iat.focalMean(focalNeighborhood)
meanTile: geotrellis.raster.Tile = DoubleArrayTile([D@7e31c125,9,4)

scala> meanTile.getDouble(0, 0)  // Should equal (1 + 7 + 9) / 3
res1: Double = 5.666666666666667

Documentation

Documentation is available at geotrellis.io/documentation.

Scaladocs for the the master branch are available here.

Further examples and documentation of GeoTrellis use-cases can be found in the docs/ folder.

Contributing

Feedback and contributions to the project, no matter what kind, are always very welcome. A CLA is required for contribution, see Contributing for more information. Please refer to the Scala style guide for formatting patches to the codebase.

Where is our commit history and contributor list prior to Nov 2016?

The entire old history is available in the _old/master branch.

Why?

In November 2016, GeoTrellis moved it's repository from the GeoTrellis GitHub Organization to it's current home in the LocationTech GitHub organization. In the process of moving our repository, we went through an IP review process. Because the Eclipse foundation only reviews a snapshot of the repository, and not all of history, we had to start from a clean master branch.

Unfortunately, we lost our commit and contributor count in the move. These are significant statistics for a repository, and our current counts make us look younger than we are. GeoTrellis has been an open source project since 2011. This is what our contributor and commit count looked like before the move to LocationTech:

Commit and contributor count before LocationTech move

Along with counts, we want to make sure that all the awesome people who contributed to GeoTrellis before the LocationTech move can still be credited on a contributors page. For posterity, I will leave the following contributors page to what it was before the move:

https://github.com/lossyrob/geotrellis-before-locationtech/graphs/contributors

Tie Local History to Old History

You can also tie your local clone's master history to the old history by running

> git fetch origin refs/replace/*:refs/replace/*

if origin points to https://github.com/locationtech/geotrellis. This will allow you to see the old history for commands like git log.