Hallo, Claude Heiland-Allen hat gesagt: // Claude Heiland-Allen wrote:
mark edward grimm wrote:
Is is possible to play a midifile in reverse
Sure, if you want each note-off message to happen before its
corresponding note-on messages!Actually doing it might be difficult though - MIDI files have
variable-length fields, so you probably have to decode *all* of it into
some other format or data structure before you start playing from the end.
This actually isn't too hard if some external tools are allowed. In the rj-library, the help file for [c_seqplay] contains an example how to convert a midi file to a text file, that [qlist] can read (using Cyclon's [seq] instead of [midifile]). Once you have the qlist-file, you can reverse it using for example the "tac" command in Linux/OS-X - "tac" is the opposite of "cat".
As qlist-files encode delta times or times between events, loading this reversed file into qlist will make it play back the whole midi file backwards.
As you noted, the notoffs then happen before the noteoffs, so some additional tweaking may be wanted, either to the file format or to your Pd player logic.
Frank