Hey! Long time no post here on DEV. I've been dealing with my mental health issue for a while. I was diagnosed with Bipolar-mixed with Depression and Anxiety a while back after a village hacking group played with me(they're still on the run but are currently under surveillance).

Anyway, here's a quick post to check on how to display the tempo of an audio using librosa. You can check the ipython notebook in google colab if you wish to.

I'm using our song We are Monsters. Check it out if you like it.

You can follow the installation process in their documentation or follow this article 😉

Install and import librosa

python -m pip install librosa
import librosa

Upload and load the audio file in the notebook as a waveform in y and store the sample rate as sr

audio_file = librosa.load('We Are Monsters.wav')
y, sr = audio_file

Then load the tempo tracker to get the estimated tempo of the track

tempo, beat_frames = librosa.beat.beat_track(y=y, sr=sr)
print('Estimated tempo: {:.2f} beats per minute'.format(tempo))

Estimated tempo: 161.50 beats per minute

We then convert the beat frames into timings and get the estimated tempo of the track

beat_times = librosa.frames_to_time(beat_frames, sr=sr)
beat_times

Output:

array([ 1.39319728, 1.76471655, 2.15945578, 2.5077551 ,
2.85605442, 3.27401361, 3.66875283, 4.04027211,
4.41179138, 4.78331066, 5.15482993, 5.50312925,
5.87464853, 6.2461678 , 6.59446712, 6.96598639,
7.31428571, 7.68580499, 8.05732426, 8.42884354,
8.80036281, 9.17188209, 9.54340136, 9.91492063,
10.26321995, 10.61151927, 10.98303855, 11.33133787,
11.70285714, 12.07437642, 12.42267574, 12.77097506,
13.14249433, 13.4675737 , 13.81587302, 14.16417234,
14.51247166, 14.86077098, 15.20907029, 15.55736961,
15.92888889, 16.32362812, 16.69514739, 17.06666667,
17.4614059 , 17.83292517, 18.20444444, 18.57596372,
18.94748299, 19.31900227, 19.69052154, 20.06204082,
20.43356009, 20.82829932, 21.22303855, 21.59455782,
21.9660771 , 22.33759637, 22.70911565, 23.05741497,
23.40571429, 23.77723356, 24.14875283, 24.49705215,
24.86857143, 25.21687075, 25.56517007, 25.91346939,
26.28498866, 26.63328798, 26.9815873 , 27.32988662,
27.67818594, 28.02648526, 28.37478458, 28.7230839 ,
29.11782313, 29.4893424 , 29.86086168, 30.23238095,
30.60390023, 30.9754195 , 31.34693878, 31.71845805,
32.08997732, 32.4614966 , 32.83301587, 33.18131519,
33.55283447, 33.9475737 , 34.31909297, 34.69061224,
35.06213152, 35.45687075, 35.82839002, 36.1999093 ,
36.59464853, 36.9661678 , 37.33768707, 37.7324263 ,
38.10394558, 38.47546485, 38.87020408, 39.2185034 ,
39.59002268, 39.96154195, 40.30984127, 40.65814059,
41.00643991, 41.35473923, 41.70303855, 42.05133787,
42.39963719, 42.74793651, 43.09623583, 43.44453515,
43.79283447, 44.14113379, 44.48943311, 44.83773243,
45.18603175, 45.53433107, 45.85941043, 46.20770975,
46.55600907, 46.90430839, 47.25260771, 47.60090703,
47.94920635, 48.29750567, 48.64580499, 48.99410431,
49.34240363, 49.69070295, 50.03900227, 50.38730159,
50.73560091, 51.08390023, 51.4554195 , 51.80371882,
52.15201814, 52.50031746, 52.84861678, 53.1969161 ,
53.54521542, 53.91673469, 54.26503401, 54.63655329,
55.03129252, 55.40281179, 55.79755102, 56.16907029,
56.54058957, 56.9353288 , 57.28362812, 57.65514739,
58.02666667, 58.39818594, 58.76970522, 59.14122449,
59.53596372, 59.93070295, 60.30222222, 60.6737415 ,
61.04526077, 61.41678005, 61.76507937, 62.11337868,
62.48489796, 62.85641723, 63.22793651, 63.62267574,
63.99419501, 64.36571429, 64.73723356, 65.08553288,
65.45705215, 65.82857143, 66.2000907 , 66.57160998,
66.94312925, 67.31464853, 67.66294785, 68.03446712,
68.40598639, 68.77750567, 69.12580499, 69.49732426,
69.86884354, 70.26358277, 70.63510204, 71.00662132,
71.37814059, 71.74965986, 72.09795918, 72.4462585 ,
72.79455782, 73.14285714, 73.49115646, 73.86267574,
74.21097506, 74.55927438, 74.9075737 , 75.25587302,
75.60417234, 75.95247166, 76.30077098, 76.64907029,
76.99736961, 77.34566893, 77.69396825, 78.04226757,
78.39056689, 78.73886621, 79.08716553, 79.43546485,
79.76054422, 80.10884354, 80.45714286, 80.80544218,
81.1537415 , 81.50204082, 81.85034014, 82.19863946,
82.54693878, 82.8952381 , 83.24353741, 83.59183673,
83.94013605, 84.28843537, 84.63673469, 84.98503401,
85.33333333, 85.68163265, 86.02993197, 86.37823129,
86.72653061, 87.12126984, 87.49278912, 87.86430839,
88.23582766, 88.60734694, 88.95564626, 89.30394558,
89.6522449 , 90.00054422, 90.34884354, 90.72036281,
91.06866213, 91.41696145, 91.83492063, 92.25287982,
92.64761905, 93.01913832, 93.3906576 , 93.76217687,
94.13369615, 94.50521542, 94.87673469, 95.24825397,
95.61977324, 95.99129252, 96.38603175, 96.75755102,
97.12907029, 97.50058957, 97.87210884, 98.24362812,
98.63836735, 99.00988662, 99.3814059 , 99.77614512,
100.1476644 , 100.51918367, 100.86748299, 101.23900227,
101.61052154, 102.00526077, 102.37678005, 102.74829932,
103.11981859, 103.46811791, 103.83963719, 104.21115646,
104.58267574, 104.95419501, 105.32571429, 105.69723356,
106.06875283, 106.46349206, 106.83501134, 107.20653061,
107.57804989, 107.92634921, 108.29786848, 108.66938776,
109.06412698, 109.43564626, 109.80716553, 110.17868481,
110.55020408, 110.92172336, 111.29324263, 111.68798186,
112.08272109, 112.45424036, 112.82575964, 113.19727891,
113.56879819, 113.96353741, 114.33505669, 114.70657596,
115.10131519, 115.47283447, 115.84435374, 116.21587302,
116.61061224, 116.98213152, 117.35365079, 117.74839002,
118.1199093 , 118.49142857, 118.86294785, 119.23446712,
119.60598639, 119.97750567, 120.34902494, 120.74376417,
121.11528345, 121.48680272, 121.88154195, 122.27628118,
122.64780045, 122.99609977, 123.36761905, 123.73913832,
124.13387755, 124.50539683, 124.8769161 , 125.22521542,
125.59673469, 125.96825397, 126.33977324, 126.73451247,
127.10603175, 127.50077098, 127.87229025, 128.26702948,
128.63854875, 129.01006803, 129.35836735, 129.75310658,
130.1478458 , 130.51936508, 130.8676644 , 131.23918367,
131.58748299, 131.95900227, 132.33052154, 132.67882086,
133.07356009, 133.46829932, 133.81659864, 134.21133787,
134.6060771 , 134.97759637, 135.34911565, 135.74385488,
136.1385941 , 136.51011338, 136.88163265, 137.25315193,
137.6246712 , 137.99619048, 138.3444898 , 138.71600907,
139.1107483 , 139.50548753, 139.85378685, 140.22530612,
140.57360544, 140.94512472, 141.33986395, 141.71138322,
142.08290249, 142.47764172, 142.82594104, 143.19746032,
143.56897959, 143.94049887, 144.31201814, 144.72997732,
145.1014966 , 145.49623583, 145.91419501, 146.3321542 ,
146.70367347, 147.0984127 , 147.46993197, 147.84145125,
148.21297052, 148.5844898 , 148.97922902, 149.37396825,
149.74548753, 150.14022676, 150.51174603, 150.88326531,
151.25478458, 151.62630385, 151.99782313, 152.3693424 ,
152.74086168, 153.11238095, 153.46068027, 153.83219955,
154.22693878, 154.5752381 , 154.92353741, 155.27183673,
155.64335601, 155.99165533, 156.3631746 , 156.71147392,
157.0829932 , 157.47773243, 157.87247166, 158.26721088,
158.6155102 , 159.01024943, 159.35854875, 159.73006803,
160.1015873 , 160.44988662, 160.84462585, 161.21614512,
161.5876644 , 161.98240363, 162.3539229 , 162.70222222,
163.0737415 , 163.42204082, 163.79356009, 164.16507937,
164.53659864, 164.90811791, 165.25641723, 165.62793651,
165.99945578, 166.3477551 , 166.69605442, 167.04435374,
167.41587302, 167.81061224, 168.18213152, 168.53043084,
168.90195011, 169.27346939, 169.62176871, 169.94684807,
170.29514739, 170.64344671, 170.99174603, 171.36326531,
171.73478458, 172.12952381, 172.50104308, 172.87256236,
173.26730159, 173.63882086, 174.03356009, 174.40507937,
174.79981859, 175.19455782, 175.5660771 , 175.96081633,
176.3323356 , 176.70385488, 177.07537415, 177.49333333,
177.84163265, 178.21315193, 178.60789116, 179.00263039,
179.39736961, 179.76888889, 180.14040816, 180.51192744,
180.88344671, 181.25496599, 181.62648526, 181.99800454,
182.36952381, 182.74104308, 183.13578231, 183.50730159,
183.90204082, 184.27356009, 184.64507937, 185.03981859,
185.41133787, 185.8060771 , 186.17759637, 186.52589569,
186.87419501, 187.22249433, 187.59401361, 187.98875283,
188.36027211, 188.75501134, 189.14975057, 189.5444898 ,
189.93922902, 190.33396825, 190.72870748, 191.10022676,
191.49496599, 191.88970522, 192.28444444, 192.67918367,
193.09714286, 193.44544218, 193.84018141, 194.23492063,
194.62965986, 195.02439909, 195.41913832, 195.7906576 ,
196.18539683, 196.58013605, 196.97487528, 197.36961451,
197.76435374, 198.13587302, 198.50739229, 198.90213152,
199.25043084, 199.62195011, 199.99346939, 200.36498866,
200.73650794, 201.13124717, 201.50276644, 201.87428571,
202.24580499, 202.59410431, 202.96562358, 203.33714286,
203.73188209, 204.08018141, 204.42848073, 204.8 ,
205.17151927, 205.51981859, 205.93777778, 206.30929705,
206.68081633, 207.0523356 , 207.44707483, 207.8185941 ,
208.19011338, 208.56163265, 208.90993197, 209.28145125,
209.65297052, 210.0244898 , 210.39600907, 210.7907483 ,
211.16226757, 211.53378685, 211.88208617, 212.25360544,
212.62512472, 213.01986395, 213.41460317, 213.76290249,
214.15764172, 214.50594104, 214.87746032, 215.24897959,
215.64371882, 216.03845805, 216.40997732, 216.7814966 ,
217.15301587, 217.5477551 , 217.91927438, 218.29079365,
218.66231293, 219.0338322 , 219.38213152, 219.75365079,
220.12517007, 220.47346939, 220.84498866, 221.19328798,
221.56480726, 221.93632653, 222.3078458 , 222.65614512,
223.05088435, 223.42240363, 223.7939229 , 224.16544218,
224.53696145, 224.90848073, 225.28 , 225.62829932,
225.97659864, 226.34811791, 226.69641723, 227.04471655,
227.41623583, 227.76453515, 228.15927438, 228.55401361,
228.94875283, 229.34349206, 229.71501134, 230.08653061,
230.43482993, 230.80634921, 231.17786848, 231.5261678 ,
231.89768707, 232.26920635, 232.61750567, 232.98902494,
233.36054422, 233.73206349, 234.10358277, 234.47510204,
234.82340136, 235.19492063, 235.56643991, 235.93795918,
236.33269841, 236.70421769, 237.07573696, 237.44725624,
237.79555556, 238.16707483, 238.5385941 , 238.91011338,
239.28163265, 239.65315193, 240.00145125])

Conclusion

There's a lot you can do with librosa like Feature Exraction, displaying an audio's spectogram, add effects to songs, check the beat and tempo of a song, and many more. Anyway, I'm still learning this library, any advice or challenge on anything about this library can be very helpful. 👍

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