Re: [Matplotlib-users] Re: drawing the GPS data on the map

Petr Jakes wrote:

>I am trying to think how to convert image (scanned map) to the Numeric array.
>My map is in Transverse Mercator projection  (this is my intended
>target projection as well) and it has WGS84 coordinates (datum) on it.
>
>I just can't figure out, how I can identify the exact pixel, where (at
>least) the 3 wgs84 coordinates intersection point are located. I think
>I need such a identification so I will be able to assign the
>information about position (coordinates) to each image pixel during
>the conversion of the image to the Numeric array? Maybe there is some
>general function how to "calibrate" the picture(pixels) to the coordinates.
>
>Any idea about it? Or is my approach completely wrong?
>
>Thks and regards
>
>Petr
>
>  
>

Petr:  I think the best approach would be make your scanned map into a 
'georeferenced' image (such as a geotiff).  I think you can do this with 
gdal (http://gdal.maptools.org).  Once the image is georeferenced, I can 
give you an example showing how to read it in using the python gdal 
module, convert it to an array and plot it with basemap.  Sorry I can't 
be of more help, but this is really outside my realm of expertise.

-Jeff

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