<div>Hello..</div> <div> </div> <div>I am trying to find a more accurate geo transform than the least squares used</div> <div>in the GDALGCPsToGeoTransform API.</div> <div> </div> <div>I would like to use the thin plate splines, but am having trouble getting good results.</div> <div> </div> <div>I am trying to use a reference image with 8 GCPs, and the image transformer with</div> <div>the nOrder = -1 argument. Is this a feasible approach?</div> <div> </div> <div>I continually get a resulting geo transform with values on the order of 1e+70 (someone</div> <div>may have seen this?).</div> <div> </div> <div>Here's the procedure I used:</div> <div> </div> <div>1) Load a JPEG raster (it will be the hSrcDS).</div> <div>2) Set the dataset's projection (as generic WGS-84).</div> <div>3) Set the dataset's GCPs.</div> <div>4) Create the img transform object, using NULLs in the destination parameters.
(I wanted to go from pixel/line to georef).</div> <div>5) Get the dest geo transform and warped image size with the GDALGetSuggestedWarpOutput API.</div> <div>6). Create the new vrt warped dataset with the image size and geo transform in 5) and</div> <div> the warp options object required to do the warping.</div> <div>7). Warp the image.</div> <div>8). Cleanup/render.</div> <div> </div> <div>I am getting a strange image that contains the correct color data + black filler pixels but is curved in a semicircular pattern. I assume that this is not the intent of the warper or</div> <div>I have not set it up correctly. Can anyone help?</div> <div> </div> <div>Thanks,</div> <div> </div> <div>Chris Pozsgai</div><BR><BR><p> 
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