On Thu, 17 Jun 2004, Chris Cannam wrote: > music, I might get two staffs with eight or nine voices on each. Not > ideal for piano music, then. That's not too problematic because the > default mode in NoteEdit appears to be to edit all voices at once, > right? Can I merge selected voices as well? Just now I created Beethoven's Sonata No.8 in C-, Op.13 'Pathetique' (530 measures) from: http://www.stormloader.com/users/beethoven/midi.htm The result is: 2 staff with 4 voices each. I used the TSE3 --> Merge... feature because the MIDI file has 5(!) tracks. (Unfortunataly, this feature doesn't work in noteedit-2.6.0. I'll fix this together with Dave Phillips' problems) The main parts are playable. The problem is the MIDI file: Beethoven wrote: |\ |\ |\ |\ |\ |\ ---------|\------------|\------------|\------------|\------------|\------------|\--- ---------|-------------|-------------|-------------|-------------|-------------|---- --|\----/-------|\----/-------|\----/-------|\----/-------|\----/-------|\----/----- --|\------------|\------------|\------------|\------------|\------------|\---------- --|-------------|-------------|-------------|-------------|-------------|----------- / / / / / / But on MIDI file is: |\ |\ |\ |\ |\ |\ ---------|\------------|\------------|\------------|\------------|\------------|\--- ----\----|-------------|-------------|-------------|-------------|-------------|---- ---\/---/-------------/-------------/-------------/-------------/-------------/----- ---/-------------------------------------------------------------------------------- ------------------------------------------------------------------------------------ \ \ \ \ \ \ | | | | | | | | | | | | |-------------|-------------|-------------|-------------|-------------| actually distributed over 2 staves. Of course, NoteEdit cannot comprehend this and computes 2 voices :-( The reason for the: NMidiTimeScale::findPathsInChunk" Error Code is: 1" is certainly the the TSE3 sustain problem, because the 'Pathetique' is certainly a good test example. > How do you decide whether to run this algorithm at all? I mean, how > can you know at the outset whether a track is expected to contain > one, two, or several voices? I imagine you could find a division > into "voices" of pretty much any MIDI track with chords in it. > > (pause while I try out the feature) > > Yes, it looks like it runs on every MIDI file -- Yes, indeed: But if all works(?) there shouldn't be unnessesary voices. Imagine the events are so: pitch 4: |---ev2--| |--ev6--| pitch 3: |--ev1 --| |--ev5--| pitch 2: pitch 1: |--ev4----------| pitch 0: |--ev3--| | | | | | | | --> time 0 4 8 16 24 32 40 And PITCH_DIST_COST_FAC = 2 and START_DIST_FAC = 20 then according to: if (MidiOnTime(j) - (MidiOffTime(i) < 0) { costs(i, j) = infinity } else { costs(i, j) = PITCH_DIST_COST_FAC * |(pitch(i) - pitch(j))| + START_DIST_FAC * (MidiOnTime(j) - (MidiOffTime(i)) } the cost matrix is: To: | 1 | 2 | 3 | 4 | 5 | 6 | --------|------|------|------|------|------|------| from: 1 |infty | 2 | 86 | 244 | 560 | 722 | --------|------|------|------|------|------|------| from: 2 |infty |infty | 8 | 166 | 482 | 640 | --------|------|------|------|------|------|------| from: 3 |infty |infty |infty | 2 | 326 | 488 | --------|------|------|------|------|------|------| from: 4 |infty |infty |infty |infty | 4 | 166 | --------|------|------|------|------|------|------| from: 5 |infty |infty |infty |infty |infty | 2 | --------|------|------|------|------|------|------| from: 6 |infty |infty |infty |infty |infty |infty | --------|------|------|------|------|------|------| The first event is evt1, the last evt6. As you can see the shorest path from evt1 to evt6 is: evt1 --> evt2 --> evt3 --> evt4 --> evt5 --> evt6 The sum is: 2 + 8 + 2 + 4 + 2 = 18 There is certainly no shorter path from evt1 to evt6 in the graph: |------- e1 \---------- | / | | | -- e2--|-- e5 ---- | | | | \ | / | | | | | | / - \ | | | |--|- e3 -|-- e6-----|-| | \ | / / \ --- e4 ------- And this computes Dijkstra's shortest path algorithm. Because all notes are marked in first loop there is no need for a 2nd loop and all events belong to the one-and-only (and 1st) voice. As explained above: (If all works correctly) the algorithm computes multiple voices only if the MIDI events overlap. If so, such score is produced: |\ -----|-------------- -----/-------------- -------------------- -------------------- -----\-------------- | | How can I merge this ? Such a way: |\ -----|---------------- ----/|---------|\----- -----|---------|------ -----|---------|------ ----/---------/------- \-----/ Ok, but how to merge this: |\ |\ |\ |\ |\ | |\ | | | |\ | | | ---|--/----/----/----/----/.-------/----/---|---- ---|----------------------------------------|---- ---|----------------------------------------|---- ---|----------------------------------------|---- ---|--\---------\-------------\.--------\---|---- | | | | | | | |/ > btw, how does NoteEdit quantize on MIDI import? Dynamically! The snap value is computed from MIDI note length. -- J.Anders, Chemnitz, GERMANY (ja@xxxxxxxxxxxxxxxxxxxxxxxxx)
