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How to Determine the world map size in pixels given this data?

Map size of a particular area say, for example:

Makati city, Philippines with bounds:

Top-Right: 121.0281, 14.56497

Bottom-Left: 121.0144, 14.54637

Image size: width="4095px" height="4095px"

Scale: at zoom level 17 | 1:4,000

Now my question is... how can I know the size of the world map in pixels using these available data?

I'm still new to geographic information systems.... so please if possible make it understandable for a novice like me... :)

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Hmm...The world spans 360 degrees of longitude and 180 degrees of latitude. This map requires 4095 pixel widths for 121.0281 - 121.0144 = 0.0137 degrees of longitude and 4095 pixel heights for 14.56497 - 14.54637 = 0.0186 degrees of latitude. Therefore, to maintain the same scale, it would require 4095 * (360 / 0.0137) = 107,605,839 pixel widths and 4095 * (180 / 0.0186) = 39,629,032 pixel heights for a total of 3,971,453 Gigapixels = 3,972 Terapixels = 4 Petapixels. I think Sony is developing a Petapixel video monitor slated for release in the year 2149. Can you wait that long? –  whuber Jan 11 '13 at 15:43
    
@whuber Thanks for the Formula... :) very good analysis here... im using it now and works Great... :) –  dicenice Jan 15 '13 at 3:29
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1 Answer 1

up vote 3 down vote accepted

You have tagged your question with OpenStreetMap, so I am assuming you are interested in the data in OSM's zoom levels.

Please have a look at: Zoom Levels

Usually you would not look at the whole world, at the same zoom level, as you would a small city. Your example is at zoom level 17, which has a scale of 1:4000.

You would look at the world either at zoom level 1 or 2.

This is because, at higher zoom levels, a humungous number of tiles would be required. How many you ask? Look at this page: Tile Disk Usage

You will see that at zoom level 17, there are 17,179,869,184 tiles, out of which 429,535,936 have been seen so far. Each is 256 by 256 pixels. And that is a lot of pixels.

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Hi... just what i wanted.... :D i'm only concerned with the numbers... since i'll be using it on my formula. i won't be downloading the tiles.... by the way how did you come up with 429,535,936? can you give me the formula? ratio of the map? or the exact width,height of the image in pixels.... Thanks :) –  dicenice Jan 11 '13 at 8:22
    
@dicenice: All of that is present in the two pages I have linked. The number of tiles comes from the second link. Each tile is of 256 by 256 pixels. at Zoom level 17, the scale is 1:4000 –  Devdatta Tengshe Jan 11 '13 at 8:53
    
@dicenice: A small correction. The total number of tiles is 17,179,869,184, out of which only 429,535,936 have data or have been seen. –  Devdatta Tengshe Jan 11 '13 at 8:55
    
thanks... got it already... ^_^ many thanks to you...... i wish i could up your answer.. too bad i still have 6 reps.... Thanks anyway :) –  dicenice Jan 11 '13 at 9:54
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