Getting Lat/Lon from X,Y Pixel Coordinates

Discussion created by vgensini on Mar 8, 2013
Latest reply on Mar 11, 2013 by MKennedy-esristaff
I'm having difficulty calculating the latitude and longitude values of an image that I am hosting inside of a div tag on my webpage. I can easily figure out the x,y (pixel) coordinates of the image and save them to a variable inside of my script. Here's the tricky part...

The map is not a mercator projection, so I cannot simply linearly interpolate the x,y pixel coordinates to lat and lon values. However, I do have the luxury of knowing the latitude and longitude of all four corners of the image (see posted diagram), projection of the map on the image, central meridian, and latitude of origin.


The 800x600 pixel image is of the U.S. and I am basically trying to capture the latitude and longitude on click by passing the x,y pixel coordinates. I am assuming I will need some sort of transformation function.