完美，同志，完美！！！！！！！

old-things/bgArrayLib/bpm.py

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+import mido
+import numpy
+
+'''
+bpm
+bites per minutes
+每分钟的拍数
+'''
+
+def mt2gt(mt, tpb_a, bpm_a):
+    return round(mt / tpb_a / bpm_a * 60)
+
+
+def get(mid:mido.MidiFile) -> int:
+    '''传入一个 MidiFile, 返回其音乐的bpm
+    :param mid : mido.MidFile
+        mido库识别的midi文件数据
+    :return bpm : int
+    '''
+    # mid = mido.MidiFile(mf)
+    length = mid.length
+    tpb = mid.ticks_per_beat
+    bpm = 20
+    gotV = 0
+
+    for track in mid.tracks:
+        global_time = 0
+        for msg in track:
+            global_time += msg.time
+            if msg.type == "note_on" and msg.velocity > 0:
+                gotV = mt2gt(global_time, tpb, bpm)
+    errorV = numpy.fabs(gotV - length)
+    last_dic = {bpm: errorV}
+    if last_dic.get(bpm) > errorV:
+        last_dic = {bpm: errorV}
+    bpm += 2
+
+    while True:
+        for track in mid.tracks:
+            global_time = 0
+            for msg in track:
+                global_time += msg.time
+                if msg.type == "note_on" and msg.velocity > 0:
+                    gotV = mt2gt(global_time, tpb, bpm)
+        errorV = numpy.fabs(gotV - length)
+        try:
+            if last_dic.get(bpm - 2) > errorV:
+                last_dic = {bpm: errorV}
+        except TypeError:
+            pass
+        bpm += 2
+        if bpm >= 252:
+            break
+    print(list(last_dic.keys())[0])
+    return list(last_dic.keys())[0]
+
+
+def compute(mid:mido.MidiFile):
+    answer = 60000000/mid.ticks_per_beat
+    print(answer)
+    return answer
+
+
+if __name__ == '__main__':
+    mid = mido.MidiFile(r"C:\Users\lc\Documents\MuseScore3\乐谱\乐谱\Bad style - Time back.mid")
+    get(mid)
+    compute(mid)