Ian, OS MasterMap is supplied in gzip compressed GML files. In its decompressed form MasterMap is approximately 20-30 times larger than Land-Line. Some approximate sizes for GB coverage of Land-Line and MasterMap are:
OS MasterMap independent polygon gzip format: 31.5 Gb OS MasterMap topological polygon gzip format: 24 Gb Land-Line NTF format: 32 Gb Land-Line DXF(tm) format: 117 Gb To give you some idea of sizes of data on a city basis, decompressed GML for Birmingham is 940Mb for an area covering 266.976km2 Of course, you need to get the GML into MapInfo format. As an example, a 10 km square area covering Bath and its surroundings is 36.2Mb in compressed GML. Translated into MapInfo format it is roughly 400Mb. Therefore a good rule of thumb would be to say that MapInfo MasterMap is approximately ten times larger than the compressed GML, this of course assumes you keep full attribution - which may or may not be necessary for your requirements! Check out the OS web site for more information on MasterMap - as well as the complete user guide in pdf format which contains all this information and more! Hope this helps! -------------------------------- Colin Henderson GI Developer Ordnance Survey Tel: (0)2380 79 2034 -------------------------------- This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the [EMAIL PROTECTED] For more information on Ordnance Survey products and services, visit our web site at http://www.ordnancesurvey.co.uk -----Original Message----- From: Ian Hull [mailto:[EMAIL PROTECTED]] Sent: 11 July 2002 12:36 To: [EMAIL PROTECTED] Subject: MI-L UK only - OS MasterMap Hi, I'm trying to figure future disk space requirements when we switch from LandLine to MasterMap. Does anyone know roughly (10x,15x,20x ...?) the relative file sizes of MapInfo tables from LandLine and MapInfo tables from MasterMap? thanks, Ian Hull Greater Manchester Transportation Unit Salisbury House Granby Row Manchester M1 7AH Tel: 0161 455 2059 Fax: 0161 455 2071 E-mail: [EMAIL PROTECTED] ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept for the presence of computer viruses. Please contact [EMAIL PROTECTED] with any queries ************************************************************ --------------------------------------------------------------------- List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] ******************************************************************** This Email and any attachments has been virus checked upon receipt at the OS and is free of all known viruses. ******************************************************************** *************************************************************** For more information on Ordnance Survey products and services, visit our web site at http://www.ordnancesurvey.co.uk *************************************************************** --------------------------------------------------------------------- List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
