Hi all.

I'm looking for some ideas on a project that i'm researching.

I must create a coverage type map using data that's in fact a massive
TIFF format image.

Looks like i can use the PHP function imagecolorat() to get the RGB
values of the pixel that corresponds to a lat/lng.
So i want to extract pixel RGB values to represent coverage on a 100m
square grid, and build a database from those values.

http://uk.php.net/manual/en/function.imagecolorat.php

I'm assuming that opening a large TIFF image and reading the RGB pixel
values for a lat/lng each time someone uses the map will be far too
much strain on the server...
Would opening a many MBs size image and getting a pixel value be a
strain on the server?
I don't know the size of the image just that it's a massive file!

Now i've spent a while searching for info on geospatial databases but
not found anything that suggests how i can store my data - the data
will be a value between 1 and 4 for each 100m square of the area that
the map represents.

What geospatial types can i save my data as so i can easily create a
query to return coverage for a lat/lng?

I was hoping to use MySQL's built in geospatial functions for this -
if i use any other database then there is no guarantee my client's
webserver will support it.

Thanks for any help and suggestions - a link to any relevant tutorials
would be handy.

Martin.

PS Is there a MySQL group i could post this question to too?
(Haven't found one yet).

-- 
You received this message because you are subscribed to the Google Groups 
"Google Maps API" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/google-maps-api?hl=en.

Reply via email to