On Monday 22 December 2008 14:21:25 Jukka Rahkonen wrote: > > I thought I was clever enough to upload 17 aerial photos of my home town > > to which I have paid for free use (copyright retained by the aerial > > photography firm) but when it came to complications of georectification I > > stalled. So I agree a bit more help would be useful except how many > > people have use of such photos? Mine are 4MB jpegs and with overlap they > > cover about 5km by 5km. > > If you can acquire ground control points in some way I believe I could > guide you a bit further. What you should do first is to find a few points > from each image and measure the image coordinates (row and column of a > pixel) and real world coordinates for that same pixel in some known > projection.
I can do that by choosing 4 identifiable points (a railway bridge over a road, two roundabouts and a large fuel tank) which are near the 4 corners of an image. I can survey each of these points with a gps. I'll do this over the next few days rather than read them off another map. AJH _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
