Filtering only shows rows that match a particular rule, any active filters are shown in the status bar. If you run an autocorrection task it will only be performed on the visible records. There are currently filters available for the MusicBrainz Unique Id and the AmpliFIND Id, only one MusicBrainz filter and/or one AmpliFIND filter can be enabled at the same time.
When enabled only songs that contain the same combination of Musicbrainz Id and AmpliFIND Id same as at least one other records are displayed. This function is very useful for finding and possibly deleting duplicate versions of the same song.
When enabled only records containing a Unique File Id field that is the same as at least one other records are displayed. This function is very useful for finding and possibly deleting duplicate versions of the same song.
When enabled only records containing a Unique File Id field are shown. This function is useful for checking tracks corrected by MusicBrainz.
When enabled only records that do not contain a Musicbrainz Id field are shown. This function is useful for finding tracks that have not been matched by MusicBrainz, that may need matching manually
When enabled only records containing a AmpliFIND Id field that is the same as at least one other records are displayed, filter status is also shown in the status bar. This function is very useful for finding and possibly deleting duplicate versions of the same song.
When enabled only records containing a AmpliFIND Id are shown. This function is useful for listing tracks that have been matched by AmpliFIND.