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I have about 65000 photos, each of them a square where an inscribed circle is radius 1 degree.

Each of these photos has an associated latitude and longitude of the center.

I'm trying to figure out how to georeference these photos with gdal so that I can warp them into a large, more sane latlong coordinate system. Once I figure out one of them, it will be trivial to automate the rest, but I just can't figure out how to properly georeference an orthogonal photo.

For instance, tile 1 has a central latitude and longitude of 0. Further, along the central X-axis it occupies 1 deg and along the y-axis, it occupies 1 degree. Using the attached photo as a guide:

Reference points

NOTE: (long, lat) A: 0,0 B: 0,.5 C: .5,.5 D: 0,-.5 E:-.5,-.5

The next photo in this series along longitude would have the following coordinates:

A:1,0 B: 1,.5 C: 1.5,.5 D: 1,-.5 E:.5,-.5

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Likewise, a photo at the pole would have a central latitude of 90 and longitude of 0. So

A: 0,90 B: 0,89.5 C: 90,89.5 D: 180,89.5 E: -90,89.5

Further, the next photo in this series would be rotated by 1 degree. So

A: 1,90 B: 1,89.5 C: 91,89.5 D: -179,89.5 E: -89,89.5

An so and, so forth.

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My proposed solution is something like:

gdal_translate -a_srs "+proj=ortho +lat_0=0 +lon_0=0 +a=6378140 +b=6378140 +units=d" input_000_00.jpg output_000_00.tif

But, when I do that and attempt to warp it, I get the following:

ERROR 1: Unable to compute a transformation between pixel/line and georeferenced coordinates for test17990.tif. There is no affine transformation and no GCPs.

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You have specified degrees as units, but not added any information what coordinates your corner points have. Apart from that, +units=d is not listed with proj -lu and might be ignored.

You may try gdal_translate with -a_ullr, or add GCP points with -gcp.

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