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First, let me say that I am new to this field. I have an existing image/video viewing application. My primary goal is to implement an efficient method to determine the latitude and longitude of any pixel in an image or video frame. I know the latitude and longitude of the four corners and the center of the image/frame. I also know the projection system that the coordinates are based in.

The images in question are not maps. They are areal photographs. I cannot make assumptions about the viewing angle or anything like that.

I'm not looking to use any existing application or tool. I need to implement the necessary functionality in my own application. I am open to using a third party library if that's the best way, but my application is proprietary. So licensing is a concern.

I've been looking into this for a while now. I've read up on world files and using them for rectification. But I don't know how to create one for my image. It seems like the tutorials that I have seen make assumptions for simplicity sake that I cannot make.

I'm basically looking for a description of the necessary math to perform the required analysis and/or a good library I could use that is compatible with proprietary software. My existing application is written in c++ and c#.

I apologize if any of terminology is incorrect. Any advice would be appreciated.

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It seems to me that your Images are ALREADY georeferenced given that you already know the coordinates of your corner pixels. –  nickves Dec 6 '12 at 0:19
    
Unless you do not have access to ArcGIS, it is the right tool for the job. Having said that, there a plethora of open source GIS (like QGIS) which will also provide the required functionality. Writing a C++/C# code to georeference would be a bit of too much unnecessary hard work and re-inventing the wheel, when the objective is to have the image georeferenced. Use the following link to georeference in ArcMap: help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//… –  ujjwalesri Dec 6 '12 at 2:37
    
use gdal_translate with argument a_ullr for "assign upper left, lower right. –  mdsumner Dec 6 '12 at 10:23
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