Filename detection analyzes all of the filenames against a set of rules in order to match each filename to its appropriate layer. Filename detection also analyzes any text files to see if they may contain the correct file mappings.
When filename detection is enabled, two additional columns are shown in the Files pane: Side and Style. The Side column shows which side of the board (Top, Bottom or Inner) that filename detection has determined the file to be. The Style column shows which type of layer has been detected. The styles are: Cu (copper), Cu out (outer layer), Cu in (inner layer), Cu in/neg (inner layer negative image), SM (solder mask), No (legend), PM (paste mask), PLT (plated through drill), NPT (unplated through drill), B/B (blind or buried drill), Rou (routing or contour), Drw (drawing), Mech (mechanical), Gold (hard gold), Glue (glue layer), Assy (assembly drawing), Peeloff (peel-off mask), and v-cut (scoring).
If the autolinker is not able to match all of the image files to a layer, then the user is given the option to try autolinking with link filters.