Os tools for os

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Revision as of 00:25, 28 June 2011 by Wiki-Walkermatt (talk | contribs) (Added details of existing osmmloader)
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This page is intended as a central location for ideas feeding into creating open source tools for interacting with Ordnance Survey data / products.

Astun Technology and Faunalia are working on a set of tools to convert Ordnance Survey's GML based data sets to PostGIS or Shapefile.

OS MasterMap loader

A Simple script for loading OS MasterMap into a variety of formats including PostGIS, Shape, TAB etc. Written in Python and based on OGR.

Source code and download available on GibHub: https://github.com/AstunTechnology/osmmloader

Future enhancements

  1. Managing Change only Updates
  2. Postgres SQL to post process data to improve comparability with common client software
  3. Creation of a classification column to make styling features easier
  4. SLD and .map files to style the data

QGIS Plugins

Feel free to add possible features here for a QGIS plugin to allow users to easily interact with OS products

Importing OpenData

A nice typical process for users to follow to download OpenData would be:

  1. Select the required data from the OS OpenData download page, enter details and wait for email
  2. Paste contents of email into QGIS plugin
  3. Plugin downloads all nessisary files mentioned in email and processes them

The data processing would generally consist of unzipping the data into a data type specific subfolder of the users's "OS Data Library" and then doing some data specific pre-processing. 

Data specific pre-processing

The following tasks would be carried out on various different data types during the import process

Raster data

  • Create new or update existing .VRT layer of the raster tiles (VRTs are virtual raster layers that make multiple tiles look like one big tile)
  • Create new or update existing vector coverage layer (the vector coverage layer could be a square for each downloaded tile with an action set to open the given tile when a user clicks on it)
  • Image pyramids?

PostGIS Support

Would be nice:

  • Plugin sets up a PostGIS database easily without much user intervention
  • Plugin imports data (probably in chunks) into the database, taking care not to make duplicate features
  • Plugin handles change only updates
  • Plugin handles spatial index creation and database maintenance

General

Plugin keeps track of the last time each dataset was updated and possible lets the user know when updates are available

Ability to "backup" the library and settings, allowing the dataset to easily be transferred to another machine

Other

  • A gazateer plugin to be able to easily type in a place name to get QGIS to zoom to that location