# Thread: calculate area from map image

1. i need inch/pixel ratio of nokia map or google map

any one can help me

2. What excatly are you looking for ? basically you could check the difference of a location by using coordinate class, and our APIs do have a way on mapping pixel location from teh visible map to a coordinate, so you could do that very easily, though the value would differ between different zoom levels.

Also, if this is technology independent question, then do specify what excatly you are looking for and why, at least for me the use case is really unclear.

And if this is technology specific question, you could see the the different categories & sub categories and find out most suitable one for your questions, and ask it in there.

3. sorry for my incomplete data realy i need to calc area.
I need to know in full zoom 1 pixel = ?

4. I suppose you could check it from the code as explained. I'm rather sure its not specified in anywhere. All and all, what would be the use case for this information ?

5. Originally Posted by Abilash ov
sorry for my incomplete data realy i need to calc area.
I need to know in full zoom 1 pixel = ?
In order to know the answer to your question you need to know three things

1. How Map Providers and Overlays Work
2. Which map projection the Nokia Maps APIs use
3. The circumference of the Earth = 40,075 km

Now combining these facts together, you can tell that for a 256x256 base tile, one pixel width = 156.54 km at the equator at zoom 0, with distance halving at each subsequent zoom level. Obviously the calculations are more complex at other latitudes, as each line is stretched according to the projection. but assuming a spherical shape, the circumference at any latitude is just the circumference at the equator times the cosine of the latitude.

6. Originally Posted by symbianyucca
I suppose you could check it from the code as explained. I'm rather sure its not specified in anywhere. All and all, what would be the use case for this information ?

I need to calculate size(area) of building Or a land.realy i need google map information. Thats i can use in python.i think nokia map is not free.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•
Nokia Developer aims to help you create apps and publish them so you can connect with users around the world.