Does anyone have information about possible formats for highly compressed vector data?
Some basic requirements.
- Must be possible to read using the larger commercially available platforms. (ArcGIS, Luciad, MapInfo etc.)
- Must have tools that allows us to create files/format from other data formats (i.e. Shape)
- Speed when reading the format is important as the data is among other things used as a live map in mobile platforms. Compression speed is less important (although nice)
- Must be possible to use a map product in a wide scale range, a 50k map shall be possible to read at a 1 000 k zoom level
- Ability to do selective updates on area, feature-ID or other search criteria would be nice, but not a must.
- Memory footprint must be small, it needs to work with Windows XP and/or Windows 7 allocating less than 1GB RAM so some kind of smart cache management must be implemented
To give an idea of the required compression and as input for memory footprint requirements, I need to store approximately 1TB of shape data to a 100GB disk.
Does anyone have suggestions for good products?
Best Answer
SpatiaLite does support compressed geometry, but you will not get 10:1 compression out of it.
Your real compression performance will probably depend a lot on the data you are putting in. Is it all geometries? If you have a lot of non-spatial data (or a lot of text attributes for spatial points), then it doesn't really matter what you do the geometries - you need to find some way to compress that data instead.