This function is used to extract earliest release metadata from data downloaded from AcoustID.org. A file will not be processed if it does not have a User Defined Text Info item named Acoustid Data.
You have the option of ignoring compilations.
The algorithm weighs track contained title fields against recording title fields looking for the earliest year information. The earliest release is the release which has the best score. Note that releases with durations that differ more than five seconds from the track's duration are ignored. Also recordings with no available release year are also ignored.
The options allow you to select when current values will be overwritten. The options are based on the current value of the Original Release Time field. Note that an Original Release Time value of 0 is treated as does not exist.
The following metadata will be extracted: Original Album, Original Artist, Original Filename/Title, Original Release Time and the MusicBrainz Original Album Id UDTI.