Le vendredi 08 février 2013 23:35:26, Martin Chapman a écrit : > I asked the following a couple of weeks ago and never got a reply. Frank, > can you comment on this please? > > > > . > > > > I am trying to remap all "0" value pixels in the source images to the > value "1" in the output image using gdalwarp like so: > > > > warpOptions->padfSrcNoDataReal[bandIndex] = 0; > > warpOptions->padfSrcNoDataImag[bandIndex] = NULL; > > warpOptions->padfDstNoDataReal[bandIndex] = 1; > > warpOptions->padfDstNoDataImag[bandIndex] = NULL; > > > > 1. I am setting INIT_DEST=0.
That might be the issue actually. Try with INIT_DEST=1 or INIT_DEST=NO_DATA Using the warper to do that is however a bit overkill. You could just RasterIO(GF_Read, ) each line/block, patch values, and then write back with RasterIO(GF_Write). > > 2. not setting UNIFIED_SRC_NODATA. > > 3. the source images have no defined nodata value. > > 4. the output image has no defined nodata value. > > > > with no luck. My question is: Is gdalwarp supposed to do this? When I > look at the pixel value of the output image the black pixels are still "0" > and not "1". > > > > My input and output are both 8-bit 3 band images. I am using gdal 1.9.2. > > > > Best regards, > > Martin _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/gdal-dev
