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<DIV><SPAN style="MARGIN-TOP: 0px; FONT: 90% monospace; font-size-adjust: none; font-stretch: normal"><FONT size=3>I apologize if this has already been answered previously, but I am trying to <BR>use the GDALWarp functionality and the process appears to be working only <BR>intermittently. I am using the 1.5.0 build of GDAL. The first time I try <BR>to use the warp functions when a project is opened, the results appear to be <BR>correct. If I subsequently run the warp again (using the same data) I have <BR>been getting erroneous results. For the image warping <BR>(oOperation.ChunkAndWarpImage) the output is an all black image. For the <BR>point warping (GDALTPSTransform) the result is extremely high values. In <BR>both cases, if I set a breakpoint in the debugger post-operation, and then <BR>set the active statement to the beginning of the setup function, the warping <BR>results are suddenly correct. <BR><BR>Does anyone have experience with this type of issue with the GDALWarp <BR>library? <BR><BR>The code that shows these issues is below.. <BR><BR>Warp Image: <BR><BR>psWarpOptions->pTransformerArg = GDALCreateTPSTransformer(tieIn->Count, <BR>tiePoints, 0); <BR>psWarpOptions->pfnTransformer = GDALTPSTransform; <BR>psWarpOptions->eResampleAlg = GRA_Bilinear; <BR>GDALWarpOperation oOperation; <BR>oOperation.Initialize( psWarpOptions ); <BR>CPLErr err = oOperation.ChunkAndWarpImage(0, 0, ihOut->ImageWidth, <BR>ihOut->ImageHeight); <BR><BR><BR><BR>Warp Points: <BR><BR>GDALTransformerFunc* gFunc = <BR>(GDALTransformerFunc*)GDALCreateTPSTransformer(tieIn->Count, tiePoints, 0); <BR>GDALTPSTransform(gFunc, 0, pWarp->Count, dX, dY, dZ, iSuc); <BR><BR><BR><BR>Thanks for your help! <BR><BR>Christiaan</FONT></SPAN></DIV></body></html>