Added support for elongating note when encountering CC64

maezawa-akira · Apr 10, 2018 · f6de572 · f6de572
1 parent 7d7ea0a
commit f6de572
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Showing 2 changed files with 35 additions and 3 deletions.
diff --git a/pretty_midi/instrument.py b/pretty_midi/instrument.py
@@ -73,7 +73,7 @@ def get_onsets(self):
         # Return them sorted (because why not?)
         return np.sort(onsets)
 
-    def get_piano_roll(self, fs=100, times=None):
+    def get_piano_roll(self, fs=100, times=None, sustain_pedal_elongates_note=False, sustain_pedal_elongate_thres=64):
         """Compute a piano roll matrix of this instrument.
 
         Parameters
@@ -84,6 +84,13 @@ def get_piano_roll(self, fs=100, times=None):
         times : np.ndarray
             Times of the start of each column in the piano roll.
             Default ``None`` which is ``np.arange(0, get_end_time(), 1./fs)``.
+        sustain_pedal_elongates_note : Boolean
+            Control Change 64 (Sustain pedal) is reflected as elongation of notes.
+            Default is False, which does nothing.  If True, then CC64 value greater
+            than sustain_pedal_elongate_thres will be treated as pedal on and rest as pedal off.
+        sustain_pedal_elongate_thres : Int
+            The threshold value for treating CC64 message as elongation of note.
+            Default is ``64``
 
         Returns
         -------
@@ -113,6 +120,22 @@ def get_piano_roll(self, fs=100, times=None):
             piano_roll[note.pitch,
                        int(note.start*fs):int(note.end*fs)] += note.velocity
 
+        # Process sustain pedals
+        if sustain_pedal_elongates_note:
+            CC_SUSTAIN_PEDAL = 64
+            time_pedal_on = 0
+            is_pedal_on = False
+            for cc in [_e for _e in self.control_changes if _e.number == CC_SUSTAIN_PEDAL]:
+                time_now = int(cc.time*fs)
+                is_current_pedal_on = (cc.value > sustain_pedal_elongate_thres)
+                if not is_pedal_on and is_current_pedal_on:
+                    time_pedal_on = time_now
+                    is_pedal_on = True
+                elif is_pedal_on and not is_current_pedal_on:
+                    subpr = piano_roll[:, time_pedal_on:time_now]
+                    piano_roll[:, time_pedal_on:time_now] = np.minimum( subpr.cumsum(1), subpr.max(1)[:,np.newaxis])
+                    is_pedal_on = False
+
         # Process pitch changes
         # Need to sort the pitch bend list for the following to work
         ordered_bends = sorted(self.pitch_bends, key=lambda bend: bend.time)

diff --git a/pretty_midi/pretty_midi.py b/pretty_midi/pretty_midi.py
@@ -739,7 +739,7 @@ def get_onsets(self):
         # Return them sorted (because why not?)
         return np.sort(onsets)
 
-    def get_piano_roll(self, fs=100, times=None):
+    def get_piano_roll(self, fs=100, times=None, sustain_pedal_elongates_note=False, sustain_pedal_elongate_thres=64):
         """Compute a piano roll matrix of the MIDI data.
 
         Parameters
@@ -750,6 +750,13 @@ def get_piano_roll(self, fs=100, times=None):
         times : np.ndarray
             Times of the start of each column in the piano roll.
             Default ``None`` which is ``np.arange(0, get_end_time(), 1./fs)``.
+        sustain_pedal_elongates_note : Boolean
+            Control Change 64 (Sustain pedal) is reflected as elongation of notes.
+            Default is False, which does nothing.  If True, then CC64 value greater
+            than sustain_pedal_elongate_thres will be treated as pedal on and rest as pedal off.
+        sustain_pedal_elongate_thres : Int
+            The threshold value for treating CC64 message as elongation of note.
+            Default is ``64``
 
         Returns
         -------
@@ -763,7 +770,9 @@ def get_piano_roll(self, fs=100, times=None):
             return np.zeros((128, 0))
 
         # Get piano rolls for each instrument
-        piano_rolls = [i.get_piano_roll(fs=fs, times=times)
+        piano_rolls = [i.get_piano_roll(fs=fs, times=times,
+                                        sustain_pedal_elongates_note=sustain_pedal_elongates_note,
+                                        sustain_pedal_elongate_thres=sustain_pedal_elongate_thres)
                        for i in self.instruments]
         # Allocate piano roll,
         # number of columns is max of # of columns in all piano rolls