v0.4.0
Pre-release
Compression and compaction
What's Changed
- Made sure the parent resolution is of type int internally by @ndemaio in #26
- Implements DGGS compaction by @alpha-beta-soup in #31
- widens compression options by @alpha-beta-soup in #30
Full Changelog: v0.3.0...v0.4.0
Compaction
Sample images for compaction (https://github.com/mommermi/geotiff_sample), rounding all bands down to the nearest 100, and only compacting where all three bands with a common ancestor have the same value. (Images only showing B01, but compaction is across all bands.)
H3
rHEALPix
Geohash
S2
Compression
Sample compression results for H3, compacted as above, but at a higher maximum resolution (13); and with the following forms of compression:
| Compression | Size |
|---|---|
| none | 43 MB |
| lz4 | 5.8 MB |
| brotli | 3.3 MB |
| snappy | 6.3 MB |
| zstd | 4.9 MB |
The input image is 5.7 MB at 10 m resolution, and with whatever compression that sample image comes with.
H3 represenation of the image requires 2.091 million cells, vs 1.002 million cells for the raster (so this is 2x over-sampled). But note that sample image values are rounded to the nearest 100 for the demonstration of compaction, so the comparison really isn't 1:1.
Even higher compression and compaction would be expected for true categorical raster data (or vector data).
