[OSM-talk] unkown coordinate encoding

Nick Hill nick at nickhill.co.uk
Mon Mar 27 21:59:15 BST 2006

You may also find the numbers change substantially when you go west of 
the meridian.

West co-ordinates are negative.

It is likely that in your format, the most significant bit will either 
simply flag west of the meridian, or the number will be expressed in 2's 
complement. 2's complement is the most likely, and is a little more 

For more information on binary negation, see:

Nick Hill wrote:
> Actually, the number should probably be
> 8388608
> which is the nearest whole number in the 2^x series. So by shifting the 
> binary number 23 bits to the right, you get the integral. The least 
> significant 23 bits are the fractional.
> Nick Hill wrote:
>> Hi Ovidiu
>> Just divide the numbers by 8388611 to get the regular lat/lon 
>> co-ordinates.
>> so
>> 373101418 becomes 44.477
>> 219065058 becomes 26.114
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