Ordnance Survey – Great Britain's national mapping agency
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All the Imagery Layer images have been fully orthorectified to represent truly and accurately what is on the ground.
Provided at 25-cm resolution and 24-bit colour, each image is edgematched and colour balanced into the existing coverage and is accompanied by metadata to allow ease in data management.
Available in TIFF, JPEG, ECW and MrSID, each format is accompanied by relevant georeferencing files.
Format and compression ratios
| Image format | Compression type | Target compression ratio | Average file size |
| TIFF | Uncompressed (46Mb) |
- |
46 Mb |
| JPEG | Jpeg compression (3.67Mb) |
20:1 |
2.7 Mb |
| ECW | ECW wavelet compression (2.34Mb) | 10:1 | 2.2 Mb |
| MrSID | MrSID wevelet compression (2.2Mb) | 10:1 | 2.2 Mb |
For both ECW and MrSID files a plug-in is normally required. Customers are advised to consult the suppliers of their image viewing software to discuss format requirements prior to placing an order for imagery.
Please see our Ordering pages for more details about our convenient online ordering service.
Imagery orders are delivered by FTP, CD, DVD or hard disk. The following data volume limits define the allowable media delivery option.
|
Medium |
Delivery Size |
|
FTP |
<400 Mb |
|
CD |
<50 Gb |
|
DVD |
<250 Gb |
|
Hard disk |
>10 Gb |
Note: FTP orders are retained on the server for 22 days.
FTP orders are compressed using ZIP.
To order, or to receive a quote, please contact our Customer Service Centre on 08456 05 05 05
For further information please look at our Imagery Layer user guide
For imagery currency and coverage maps please refer to our Coverage page. Information about the current status of the Imagery Layer is updated monthly here.