I have a custom CSV file with the columns UTM easting, UTM northing, red, green, blue. The latter values represent a RGB color of the pixel value. Now I want to convert this CSV to a raster GeoTIFF. I've found that there is a import function in QGIS (Layer -> Add delimited text layer) where I can import the CSV as vector layer. How can I transform it to a raster GeoTIFF?