Autocorrect null notes, fix missing channels

Author: Cantersoft

YTPMVE.py

@@ -40,6 +40,7 @@ def exitScript(errMessage, exitCode,):
 def process_midi(MIDI_filename):
 	A440_REF = 69			#MIDI index value of A4, the universal reference note.
 
+	counter=0
 	current_time=0
 	start=0
 	MIDI_time=[]
@@ -60,6 +61,11 @@ def process_midi(MIDI_filename):
 	#Process MIDI file
 	print("Processing MIDI file.")
 	try:
+		MIDI_file_list = list(MIDI_file)
+		# We must have a 1:1 ratio of note_offs for note_ons. This will create a space in note_durations which will be filled later.
+		for i in range(len(MIDI_file_list)):
+			note_durations.append("NULL")
+			
 		for msg in MIDI_file:															   
 			current_time=float(msg.time)+current_time
 			# Change this so that we don't look at the if statement except the first few times.
@@ -71,14 +77,29 @@ def process_midi(MIDI_filename):
 				continue	
 			else:
 				MIDI_time.append(current_time)
-				# End of note.
+				# Start of note.
 				if msg.type == "note_on" and msg.velocity != 0:
+					counter += 1
 					note_channels.append(msg.channel)
 					note_tones.append(msg.note)
 					note_starts.append(current_time)
-					# We must have a 1:1 ratio of note_offs for note_ons. This will create a space in note_durations which will be filled later.
-					note_durations.append("NULL")
-				# Start of note
+					
+					#Forward note search	
+					current_time_2 = current_time
+					for counter_2 in range(1, len(MIDI_file_list)-counter):
+						msg2 = MIDI_file_list[counter+counter_2]
+						current_time_2 = current_time_2 + msg2.time
+						#we need to confirm the type has the velocity attribute before checking if the velocity is 0, otherwise an error is thrown
+						if msg2.type == "note_off" or msg2.type == "note_on": 
+							if msg2.type == "note_off" or (msg2.type == "note_on" and msg2.velocity == 0):
+								note_duration = current_time_2 - current_time
+								#Avoid zero-duration notes, which may cause crashes.
+								if note_duration == 0:
+									continue
+								note_durations[counter] = note_duration
+								break
+				
+				# End of note
 				elif msg.type == "note_off" or msg.velocity == 0:
 					#note_durations.append(msg.time)	#I think this was originally used for legato?
 					 # Reverse search the note starts list and find the note_on message that was probably linked to this note_off
@@ -88,6 +109,15 @@ def process_midi(MIDI_filename):
 							list_match=i
 							note_durations[list_match]=current_time-note_starts[i]
 							break
+			
+			#Forward search notes. This should probably be an optional feature, but for now it prevents notes from getting stuck on.
+			# for i in range(0, len(note_starts), 1):
+				# if note_durations[i] == "NULL":
+					# try:
+						# note_durations[i] = note_durations[i+1]
+					# except IndexError:
+						# pass
+				
 	except Exception as error:
 		exitScript(str(error)+". MIDI processing failed.", 1)
 

YTPMVE_UI.pyw

@@ -1,5 +1,5 @@
 #YTPMVE
-#20250126
+#20250128
 from os import path
 import tkinter as tk
 import tkinter.ttk as ttk
@@ -95,7 +95,8 @@ def set_midi_channel_titles(MIDI_file):
 			track_name = msg.name
 		#This might grab control changes unrelated to tracks? Not sure, may be an issue later and this should be refined.
 		#Update 20250125: Only control change 0 is used for bank select, which serves a similar purpose to a program change.
-		elif (msg.type == "control_change" and msg.control == 0) or msg.type == "program_change":
+		#Update 20250128: Some horribly malformed MIDIs jump right into notes and never specify which channels are being used, so note_on, and note_off messages also add channels now.
+		elif (msg.type == "control_change" and msg.control == 0) or msg.type == "program_change" or msg.type == "note_on" or msg.type == "note_off":
 			channel = msg.channel
 			if channel not in dict_midi_channels:
 				dict_midi_channels[channel] = ('Channel {}: {}'.format(channel, track_name))