I am trying to convert a shapefile into a raster, but ArcGIS gives values only to outside cells, not inside´s, so I get a raster with a hole in the inside with the shape of the feature.
How can I inverse the results?
If you convert a polyline shapefile to a raster it will generate non-nodata cells only at the locations that overlap the lines. Same goes for point shapefiles. If you want a raster covering the whole enclosed area, you need to have a polygon shapefile and convert that to a raster, meaning that you have to convert a polyline feature to polygon if that is what you have.