GNMIDI
[in menu Analyse]
This batch operation searches for similar or identical MIDI files in two folders.
Using GNMIDI Light license batch operations are not available.
Source folders
Instead of choosing one source and one destination folder (as most other batch operations ask for) you must choose two source folders. The MIDI files within these folders are not modified.
Hint: Only this batch operation allows that both folders are identical folder in order to search for similar MIDI files within one folder. In this case both folder path names must be identically, else it will be assumed that they are different folders and that would cause finding many duplicate files.
Duration
Before comparing starts it will collect MIDI files and some MIDI information from both folders. Then it will compare those MIDI files that have similiar information. The duration for this depends on number of MIDI files in the folder (and sub folders). It could take more time.
Result
At end it generates a text file and displays it with notepad editor, which contains the list of identical or similar MIDI files.
Differences
To get the difference in more detail you could compare two MIDI files.