I am trying to clip a raster using a polygon an GDAL. The following code is running without an error but the ouputimage is all zeros. All files are in the same CRS. Is there a way to use GdalWarp with Cutline?
const char* inputPath = "input.tif";
const char* outputPath = "output.tif";
//clipper Polygon
auto w_read_filenamePoly = "Polygon.shp";
char* read_filenamePoly = new char[w_read_filenamePoly.length() + 1];
wcstombs(read_filenamePoly, w_read_filenamePoly.c_str(), w_read_filenamePoly.length() + 1);
GDALDataset* hSrcDS;
GDALDataset* hDstDS;
GDALAllRegister();
hSrcDS =(GDALDataset *) GDALOpen(inputPath, GA_Update);
hDstDS = (GDALDataset*)GDALOpen(outputPath, GA_Update);
const char* proj = hSrcDS->GetProjectionRef();
const char* proj2 = hDstDS->GetProjectionRef();
//clipper Layer
GDALDataset* poDSClipper;
poDSClipper = (GDALDataset*)GDALOpenEx(read_filenamePoly, GDAL_OF_UPDATE, NULL, NULL, NULL);
Assert::IsNotNull(poDSClipper);
delete[]read_filenamePoly;
OGRLayer* poLayerClipper;
poLayerClipper = poDSClipper->GetLayerByName("Polygon");
int numClip = poLayerClipper->GetFeatureCount();
//get my geometry as OGRPolygon
std::vector<OGRFeature*> vecClipFeature;
OGRFeature* feat;
while ((feat = poLayerClipper->GetNextFeature()) != NULL)
{
vecClipFeature.push_back(feat);
}
OGRGeometry* geom = vecClipFeature.at(0)->GetGeometryRef();
OGRPolygon *clipPoly = geom->toPolygon();
//setup warp options
GDALWarpOptions* psWarpOptions = GDALCreateWarpOptions();
psWarpOptions->hSrcDS = hSrcDS;
psWarpOptions->hDstDS = hDstDS;
psWarpOptions->nBandCount = 1;
psWarpOptions->panSrcBands = (int *) CPLMalloc(sizeof(int) * psWarpOptions->nBandCount);
psWarpOptions->panSrcBands[0] = 1;
psWarpOptions->panDstBands = (int*)CPLMalloc(sizeof(int) * psWarpOptions->nBandCount);
psWarpOptions->panDstBands[0] = 1;
psWarpOptions->pfnProgress = GDALTermProgress;
psWarpOptions->hCutline = clipPoly;
// Establish reprojection transformer.
psWarpOptions->pTransformerArg = GDALCreateGenImgProjTransformer(hSrcDS,proj, hDstDS, proj2, FALSE, 0.0, 1);
psWarpOptions->pfnTransformer = GDALGenImgProjTransform;
GDALWarpOperation oOperation;
oOperation.Initialize(psWarpOptions);
oOperation.ChunkAndWarpImage(0, 0, GDALGetRasterXSize(hDstDS), GDALGetRasterYSize(hDstDS));
GDALDestroyGenImgProjTransformer(psWarpOptions->pTransformerArg);
GDALDestroyWarpOptions(psWarpOptions);
GDALClose(hDstDS);
GDALClose(hSrcDS);
Best Answer
This is a duplicate of a question on SO. There are many pitfalls when using the C++ interface.