Thank you.. I solved the problem. Cutting polygon has to be converted to pixel coordinates. I have missed that point. now it works well ..
Regards 30 May 2023 Sal 16:20 tarihinde Rahkonen Jukka < jukka.rahko...@maanmittauslaitos.fi> şunu yazdı: > Hi, > > > > I can’t really read the code, but based on what happens, maybe your > cutline is outside the image. So you > > - create an output band > - fill it with zeroes > - and then you write pixels within the cutline into the output > > Because the output stays all zeroes, and there are no errors, then I guess > that the pixels within your cutline are all nodata. > > Maybe printing the WKT out from “geom” could prove or disprove my guess. > > > > -Jukka Rahkonen- > > > > *Lähettäjä:* gdal-dev <gdal-dev-boun...@lists.osgeo.org> *Puolesta *Ahmet > Temiz > *Lähetetty:* tiistai 30. toukokuuta 2023 15.57 > *Vastaanottaja:* Norman Vine <n...@meganet.net> > *Kopio:* gdal-dev <gdal-dev@lists.osgeo.org> > *Aihe:* Re: [gdal-dev] wrong with clipping a tif file with a polygon > > > > Thank you , > > > > I already worked on that code. But clipping was not succesful. output.tif > is blank on qgis. > > > > On Tue, May 30, 2023 at 3:24 PM Norman Vine <n...@meganet.net> wrote: > > perhaps this will help > > https://stackoverflow.com/questions/70664043/clip-raster-with-polygon-with-gdal-c > > > On May 30, 2023, at 8:12 AM, Ahmet Temiz <ahmettemi...@gmail.com> wrote: > > > > Hi, > > I am trying to clip a tif file with a polygon. But resulting output.tif > file shows nothing. > > > > Where am I doing wrong ? > > > > " #include <gdal/gdal.h> > > #include <gdal/gdal_priv.h> > > #include <gdal/gdalwarper.h> > > #include <gdal/ogrsf_frmts.h> > > #include <gdal/gdalwarper.h> > > #include <string> // for string class > > using namespace std; > > > > int main() { > > const char *inputPath = "input.tif"; > > const char *outputPath = "output.tif"; > > > > // clipper Polygon > > // THIS FILE MUST BE IN PIXEL/LINE COORDINATES or otherwise one should > > // copy the function gdalwarp_lib.cpp:TransformCutlineToSource() > > // from GDAL's sources > > // It is expected that it contains a single polygon feature > > const char *read_filenamePoly = "input.geojson"; > > > > GDALDataset *hSrcDS; > > GDALDataset *hDstDS; > > > > GDALAllRegister(); > > auto poDriver = GetGDALDriverManager()->GetDriverByName("GTiff"); > > hSrcDS = (GDALDataset *)GDALOpen(inputPath, GA_ReadOnly); > > > > hDstDS = (GDALDataset *)poDriver->CreateCopy( > > outputPath, hSrcDS, 0, nullptr, nullptr, nullptr); > > // Without this step the cutline is useless - because the background > > // will be carried over from the original image > > hDstDS->GetRasterBand(1)->Fill(0); > > > > hDstDS->SetProjection(hSrcDS->GetProjectionRef()); > > > > const char *src_srs = hSrcDS->GetProjectionRef(); > > const char *dst_srs = hDstDS->GetProjectionRef(); > > printf("%s ",src_srs); > > // clipper Layer > > GDALDataset *poDSClipper; > > poDSClipper = (GDALDataset *)GDALOpenEx( > > read_filenamePoly, GDAL_OF_UPDATE, NULL, NULL, NULL); > > > > auto poLayerClipper = poDSClipper->GetLayer(0); > > auto geom = poLayerClipper->GetNextFeature()->GetGeometryRef(); > > //char* wkt = nullptr; > > if (geom != nullptr && geom->IsValid()) > > { > > printf("\n geom is valid \n"); > > } > > // 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 = geom; > > > > // Establish reprojection transformer. > > psWarpOptions->pTransformerArg = GDALCreateGenImgProjTransformer( > > hSrcDS, src_srs, hDstDS, dst_srs, TRUE, 1000, 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); > > } > > " > > > > -- > > Ahmet Temiz > > Jeoloji Müh. > > Afet ve Acil Durum Yönetimi Başkanlığı > > Deprem Dairesi Başkanlığı > > > > > > ________________________ > > > > Ahmet Temiz > > Geological Eng. > > > > Disaster and Emergency Management > > of Presidency > > _______________________________________________ > > gdal-dev mailing list > > gdal-dev@lists.osgeo.org > > https://lists.osgeo.org/mailman/listinfo/gdal-dev > > > > > -- > > Ahmet Temiz > Jeoloji Müh. > Afet ve Acil Durum Yönetimi Başkanlığı > Deprem Dairesi Başkanlığı > > > ________________________ > > Ahmet Temiz > Geological Eng. > > Disaster and Emergency Management > of Presidency >
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