project bluemarble

lastmodified on 12/11/2005

sources

Imagery was taken from nasa bluemarble project

processing

Processing was done on the data of january 2004 and the topographic map of august 2004, the large png files.
Main imagery were 8 tiles of 21600 pixels square.
Software used was java1.5 ( new ImageIO ).
Hardware used was a single opteron 146 / 3gb memory.

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| A1 | B1 | C1 | D1 | 
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| A2 | B2 | C2 | D2 | 
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Scale : subsampling rate eg. 144 is 144 times smaller.

Stepping : for that scale the stepping in longitude/lattitude in wich the images were generated.

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| Scale    | 144 | 36    | 18    | 12   | 6    | 4    | 2    | 0     |
| Stepping | 90  | 22.50 | 11.25 | 7.50 | 3.75 | 2.50 | 1.25 | 0.625 |
 --------------------------------------------------------------------

Tiles were cut at 150 pixels wide in progressive jpg format and compressed at ratio 0.5.
Images are stored in the following directory structure/naming :
/$scale/$lat.000x$long.000.jpg

Longitude goes from -90 to 90.
Lattitude goes from -180 to 180.

data

Directory structure is as follows :

user interface

Since i'm not a guru in javascript, I did my try here, but I can imagine that there is better code to do this ( code that is actually working :p )

I used as a base the code from ka-map.

On mozilla under linux, i'm still having some kind of delays ........, explorer hangs ....

If anyone finds a better way to do it -> contact mogo at mogo dot be.

Next step is to map it with 3d api....., let's first see this is working.