Licensing options for this format begin with FME Professional Edition.
Overview
The GeoPackage Tiles Reader/Writer allows FME to read and write data in the GeoPackage Tiles format.
The GeoPackage specification is an efficient format for storing tilesets in a single SQLite database file, and it is ideal for sending data over the web, or displaying data on a mobile device.
GeoPackage supports PNG, PNG8, and JPEG data stored as binary blobs in the tiles column. Additionally, it supports WEBP tiles as an extension.
A GeoPackage Tiles table is composed of tile layers called Zoom Levels. Zoom Level 0 has the least resolution, and most tiling schemes contain only 1 or 2 tiles at this level. Each successive zoom level has greater resolution than the last. In most tiling schemes, each zoom level has twice the resolution and four times as many tiles as the previous zoom level.
In FME, a single GeoPackage file is a dataset and each tiles table within the file is a feature type. Each tiles table is read and written as a single mosaicked feature with raster geometry. Each pixel color value in a tile is a value in a single FME raster feature.
Reader Overview
FME considers a single GeoPackage file to be a dataset.
The file must contain entries in the geopackage_contents table with the type tiles to be valid for reading with the GeoPackage Tiles reader.
The reader allows for selecting subsets of data based on a user-provided spatial envelope and/or a specific zoom level.
If a specific zoom level is specified, then the a mosaicked feature with raster geometry is read using the tiles at that zoom level. Otherwise a mosaicked feature is read using the tiles at the most resolute zoom level.
Writer Overview
The GeoPackage Tiles writer stores the raster tiles data inside a SQLite .gpkg file. The file does not have to exist before the translation occurs. An existing file with the same name will be overwritten with the new feature data.
Each raster feature is written as a tiles table within the GeoPackage file. The image is converted into tiles and then written to the zoom level that best matches the image resolution.
The writer allows for generating additional zoom levels and also allows various tiling schemes, image formats, and compression levels to be specified.
Writer-Level Format Parameters
The writer supports additional options through the OGC GeoPackage Tiles Writer Feature Type Parameters dialog.
FME Raster Features
FME raster features represent raster data and use several concepts that are unlike those used in the handling of vector data. The topics below describe how FME processes raster data.
GeoPackage Tiles supports rasters with up to 4 bands.