Hi, You can also correct this 5x5 problem by using gdal grid with Nearest neighbour interpolation. You could use the point data to do this.
I also post a small presentation that can help go from vector to raster with point data. Sometimes, keeping it simple is better. https://www.slideshare.net/shencoop/qgis-raster-to-point If you do decide to make a shapefile with the csv, make sure to store the coordinates in a text field. Placing the coordinates in a $x and $y object fields will lead to rounding. Any rounding would corrupt the raster therefore you need to original coordinates for this to work. This may explain your problems also. I used this method to change the geoids of a thousands of rasters because the program I was using was designed to change the z value for texte files only and not rasters (NRCAN GPS-H). Nicolas Cadieux Ça va bien aller! > Le 13 mai 2020 à 11:25, chris hermansen <[email protected]> a écrit : > > > Maria and list, > >> On Tue, May 12, 2020 at 7:00 PM Priv.-Doz. Dr. Maria Shinoto >> <[email protected]> wrote: >> Hi, >> >> Thanks for helping. -- Thanks to you and Chris Hermansen I got a result, but >> it could be better. >> >> For the records, a short explanation: >> >> ***** >> Well, I checked the properties, jgd2011 is in Meters, the raster is said to >> be 5m. In the official Japanese viewer, which creates a beautiful raster >> image without white pixels, the pixels are exactly 5m*5m. >> >> Today I tried the export to .xyz since the shapefile looked ugly, and after >> realising that the Japanese xyz is indeed yxz, everything looked fine, and I >> could store it in a Geopackage. But the grid is now 5,276m * 6,146m. But it >> fits well on top of the basemap. The basemap is of the same special Japanese >> GML format, but QGIS could read it all without problem. I do not understand >> why QGIS does not read the point data from the GML fille, but that is an >> aside, I am amazed by what QGIS actually can do. >> >> From the Geopackage I could rasterize. It is as Chris Hermansen said, >> thanks. Unfortunately, I did not get it done from the shapefiles, they >> always looked weird or like nothing, even with identical settings. But the >> geopackages from xyz tiles are fine. >> >> For resolution, I chose georeferenced units as Chris suggested, and since >> the measurement tool got some different length, I put it to 5,276m by >> 6,146m. A 5m by 5m resolution created a weird layer with horizontally >> expanding white pixels. >> >> It seems that tweaking with the resolution might lead to an even better >> result, but for the time being, it is OK as it is. >> ***** >> >> > Upon reflection I think the basic problem here is that the point data should > be interpolated to create a raster if you want a precise 5x5m resolution. > > For this, rather than use the Raster > Rasterize tool, the approach should be: > open the processing toolbox Processing > Toolbox > in the toolbox open Interpolation > TIN interpolation > in the TIN Interpolation screen: > select the Vector layer > select the Interpolation attribute > click the + to add to the vector layer panel > choose the interpolation method - probably best to use cubic > click on the ... next to extent and set it to the layer extent > set the pixel size to 5.0 and 5.0 > click Run > This way you won't have the odd sizes you mentioned. This may give you a > smoother surface in the end as well. > > > -- > Chris Hermansen · clhermansen "at" gmail "dot" com > > C'est ma façon de parler.
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