OGC GeoPackage Tiles Writer Feature Type Parameters

The tile set's name.

Sets the value of the name row in the metafile table.

Default to the basename of the filename.

The data format of the binary tile blob data stored in the tile table.

Sets the value of the format row in the metafile table if Auto is not specified. If Auto is specified, then no data will be written to the format row in the metafile table.

If the Tile format value is set, then all tile blob data will be written in the file format that is specified.

If Tile Format is set to JPEG or WEBP, this parameter sets the desired compression level of the output images. This is expressed as a percentage of the original file size. For example, setting a compression level of 75 means that the output image will be approximately 75% smaller (one-quarter of the size) than an uncompressed image.

Value: The level of compression that is used, from 1-100. The default is 75.

Note: Repeatedly reading and saving files may decrease the quality for this format. In addition, Workbench may not know which format data comes from, and whether it used lossy compression. If you know that source data comes from files with lossy compression, you should also set the compression level to 0. Although this compression still does not guarantee the exact copy of the source file, the output will be very close to the original.

If Tile Format is set to PNG, this parameter sets the PNG DEFLATE compression level.

Must be a value from 1-9. The default is 6.

If Tile Format is set to PNG8, this parameter determines if the PNG8 data will use Floyd-Steinberg dithering.

• Yes: PNG8 data will be written using Floyd-Steinberg dithering.
• No (default): No dithering will be used.

To enable use of GeoPackage with tile servicing software, you can select a predefined tiling scheme:

• GoogleCRS84Quad, which consists of a single 256x256 tile at its zoom level 0, in EPSG:4326 CRS, with extent in longitude and latitude in the range [-180,180]. Due to unused lines at zoom level 0, InspireCRS84Quad or PseudoTMS_GlobalGeodetic is recommended.
• GoogleMapsCompatible, which consists of a single 256x256 tile at its zoom level 0, in EPSG:3857 CRS, with extent in easting and northing in the range [-20037508.34,20037508.34].
• InspireCRS84Quad, which consists of two 256x256 tiles at its zoom level 0, in EPSG:4326 CRS, with extent in longitude in the range [-180,180] and in latitude in the range [-90,90].
• PseudoTMS_GlobalGeodetic, which has the same definition as the InspireCRS84Quad tiling scheme. Note, however, that full interoperability with TMS is not possible due to the origin of numbering of tiles being the top left corner in GeoPackage, whereas TMS uses the bottom left corner as origin.
• PseudoTMS_GlobalMercator, which consists of four 256x256 tiles at its zoom level 0, in EPSG:3857 CRS, with extent in easting and northing in the range [-20037508.34,20037508.34]. Note, however, that full interoperability with TMS is not possible due to the origin of numbering of tiles being the top left corner in GeoPackage, whereas TMS uses the bottom left corner as origin.

In all the above tiling schemes, consecutive zoom levels defer by a resolution of a factor of two.

Determines the resampling algorithm used:

• Bilinear (default): Use the Bilinear interpolation algorithm to construct the tile data. Calculates a pixel's value by averaging the closest 2x2 neighborhood of pixel values. This method produces a higher-quality result than Nearest Neighbor.
• Nearest-neighbor: Use the nearest-neighbor interpolation to construct the tile data. Nearest-neightbor interpolation uses the value of the nearest pixel to calculate the value of a given pixel without considering the values of pixels outside this nearest pixel range. Nearest-neighbor is the least resource-intensive, but also produces the lowest-resolution tiles.
• Cubic: Use the cubic interpolation algorithm to construct the tile data. Calculates a pixel's value by using the closest 4x4 neighborhood of pixel values.
• Cubic-spline: Use the Cubic Spline interpolation algorithm to construct the tile data. Because it calculates a pixel's value by using a spline, this results in a smaller error than linear interpolation, and the interpolation is smoother.
• Lanczos: Use the Lanczos interpolation algorithm to construct the tile data. Use Lanczos interpolation when you want to enhance or maintain local contrast; it is useful for viewing detailed features or boundaries.
• Mode: Use the Mode resampling method to construct the tile data. This is a custom resampling algorithm made by GDAL. This method will select the value which appears most often in all the sampled pixels and use that as the value for the given pixel.
• Average: Use the average resampling method to construct the tile data. This is a custom resampling algorithm made by GDAL. This method will use the average of all non-NODATA contributing pixels to compute the value of a pixel.

Sets the strategy used to determine the zoom level:

• Auto (default): Round the zoom level to the closest integer value when computing the resolution to determine the zoom level.
• Upper: Round the zoom level down when computing the resolution to determine the zoom level. For example, round 4.25 to 5. This will lead to oversampling.
• Lower: Round the zoom level up when computing the resolution to determine the zoom level. For example, round 4.75 to 4. This will lead to undersampling.

Determines whether to create additional zoom levels by resampling the original raster:

• If Yes, the writer generates zoom levels from the level below the Base Zoom Level, as determined by the Base Zoom Level Strategy parameter. It continues to generate less-resolute zoom levels until it hits the level specified in the Minimum Zoom Level parameter (described below), or until it is impossible to generate less-resolute zoom levels. The interpolation type used to resample the generated zoom levels is controlled by the Interpolation Type parameter.
• If No (default), only the base (closest to native image resolution) zoom level will be written.

Determines the least-resolute zoom level to generate when Generate Zoom Levels is set to Yes.

The default is 0, which is the lowest possible zoom level.