In order to understand what openmpt can do, you need to
understand what tracker music is. Tracker music uses ‘spreadsheet’-like
tables (called patterns) to specify which instruments or samples are to
be played at which notes in which order, with which timing and with
which effect. Typically, tracker music uses multiple of these patterns
played in a specified sequence to form a song.
Tracker music is stored in a module file format. These files are self-contained, meaning they contain all information required to play (both patterns, pattern sequences and samples / instruments). There is more information at Wikipedia. Note that the terms modules and tracker music is often used interchangeably.
openmpt
The openmpt R packages uses libopenmpt at its core. It
essentially provides R bindings to the features offered by libopenmpt.
This means that this package can read modules, play them, convert them
to other audio formats. You can also retrieve meta-information stored in
or about the module. The underpinning library does not contain entry
points to modify or edit the modules, so this is also true for the R
package.
On Windows machines you can use the OpenMPT software, which has a graphical
user interface (GUI). It allows you to compose and edit music. If you
want to stick to R you can use ProTrackR2. That
package allows you to create and modify modules in R. The
downside is that it only support ProTracker compatible module files.
What about midi files? Well midi files are no modules (i.e., not
self-contained). According to the libopenmpt documentation
it should be able to play some midi files to some extend. However, I was
not able to test this successfully. If you want to work with midi files
in R it is recommended to use fluidsynth
instead.
The comparison of openmpt and its alternatives are
sumarised in the table below.
| Software | Runs in R | Allows editing | Supported file formats | Operating systems |
|---|---|---|---|---|
openmpt
R package
|
✔ | mptm mod s3m xm it 667 669 amf ams c67 dbm digi dmf dsm dsym dtm far fmt fst imf ice j2b m15 mdl med mms mt2 mtm mus nst okt plm psm pt36 ptm sfx sfx2 st26 stk stm stx stp symmod gtk gt2 ult wow xmf gdm mo3 oxm umx xpk ppm mmcmp | Windows, MacOS, Ubuntu, Fedora | |
| OpenMPT (with GUI) | ✔ |
same as openmpt R package
|
Windows | |
ProTrackR2
R package
|
✔ | ✔ | mod (ProTracker compatible only) | Windows, MacOS, Ubuntu, Fedora |
fluidsynth
R package
|
✔ | mid | Windows, MacOS, Ubuntu, Fedora |