How to change audio playback speed using Pydub?

Question

I am new learner of audio editing libs - Pydub. I want to change some audio files' playback speed using Pydub(say .wav/mp3 format files), but I don't know how to make it. The only module I saw that could possibly deal with this problem is speedup module in effect.py. However, there is no explanation about how I am supposed to call it.

Could anyone kindly explain how to do this task in Pydub? Many thanks!

(A related question: Pydub - How to change frame rate without changing playback speed, but what I want to do is to change the playback speed without changing the audio quality.)

Specifically, I don't understand the arguments in `speedup(seg, playback_speed=1.5, chunk_size=150, crossfade=25)`, especially `chunk_size` and `crossfade`. Could anyone kindly explain them? Thanks! — itsMe, Jul 20 '18 at 04:19
Chunk size and crossfade are optional - you can just leave them out :) - a playback speed of 1.5 will play 1.5x faster than the original sound. The way it works is it splits the sound into chunks (150ms long by default) and then overlaps them to shorten the total playback duration (with crossfades of 25ms, be default) — Jiaaro, Aug 01 '18 at 04:37

score 6 · Answer 1 · answered Mar 02 '20 at 19:00

6

from pydub import AudioSegment
from pydub import effects

root = r'audio.wav'
velocidad_X = 1.5 # No puede estar por debajo de 1.0

sound = AudioSegment.from_file(root)
so = sound.speedup(velocidad_X, 150, 25)
so.export(root[:-4] + '_Out.mp3', format = 'mp3')

answered Mar 02 '20 at 19:00

Nombre Apellido

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1

This worked a lot better than other solutions I've found! Thank you. – Jesse Vincent Oct 06 '21 at 19:44
2

This actually seems to work but the quality is so bad – etayluz Aug 08 '22 at 11:23

score 5 · Answer 2 · answered Dec 10 '19 at 14:53

This can be done using pyrubberband package which requires rubberband library that can stretch audio while keeping the pitch and high quality. I was able to install the library on MacOS using brew, and same on Ubuntu with apt install. For extreme stretching, look into PaulStretch

brew install rubberband

This works simply with librosa package

import librosa
import pyrubberband
import soundfile as sf

y, sr = librosa.load(filepath, sr=None)
y_stretched = pyrubberband.time_stretch(y, sr, 1.5)
sf.write(analyzed_filepath, y_stretched, sr, format='wav')

To make pyrubberband work directly with AudioSegment from pydub without librosa I fiddled this function:

def change_audioseg_tempo(audiosegment, tempo, new_tempo):
    y = np.array(audiosegment.get_array_of_samples())
    if audiosegment.channels == 2:
        y = y.reshape((-1, 2))

    sample_rate = audiosegment.frame_rate

    tempo_ratio = new_tempo / tempo
    print(tempo_ratio)
    y_fast = pyrb.time_stretch(y, sample_rate, tempo_ratio)

    channels = 2 if (y_fast.ndim == 2 and y_fast.shape[1] == 2) else 1
    y = np.int16(y_fast * 2 ** 15)

    new_seg = pydub.AudioSegment(y.tobytes(), frame_rate=sample_rate, sample_width=2, channels=channels)

    return new_seg

Thanks -- any idea about inter-operability between `pyrubberband`/`librosa` and `pydub`? — lefft, Jan 19 '23 at 00:39
@lefft sorry I don't know. I haven't worked with either of these 3 since posting this answer. — tatarkin, Jan 20 '23 at 20:05

score 1 · Answer 3 · answered Jul 03 '20 at 12:24

I know it's late but I wrote a program to convert mp3 to different playback speed.

First, Convert the .MP3 -> .Wav because PYRubberBand supports only .wav format. Then streach the time and pitch at the same time to avoid chipmunk effect.

import wave
import sys
from pydub import AudioSegment
#sound = AudioSegment.from_file("deviprasadgharpehai.mp3")
sound = AudioSegment.from_mp3(sys.argv[1])
sound.export("file.wav", format="wav")

print(sys.argv[1])

import soundfile as sf
import pyrubberband as pyrb
y, sr = sf.read("file.wav")
# Play back at extra low speed
y_stretch = pyrb.time_stretch(y, sr, 0.5)
# Play back extra low tones
y_shift = pyrb.pitch_shift(y, sr, 0.5)
sf.write("analyzed_filepathX5.wav", y_stretch, sr, format='wav')

sound = AudioSegment.from_wav("analyzed_filepathX5.wav")
sound.export("analyzed_filepathX5.mp3", format="mp3")

# Play back at low speed
y_stretch = pyrb.time_stretch(y, sr, 0.75)
# Play back at low tones
y_shift = pyrb.pitch_shift(y, sr, 0.75)
sf.write("analyzed_filepathX75.wav", y_stretch, sr, format='wav')

sound = AudioSegment.from_wav("analyzed_filepathX75.wav")
sound.export("analyzed_filepathX75.mp3", format="mp3")

# Play back at 1.5X speed
y_stretch = pyrb.time_stretch(y, sr, 1.5)
# Play back two 1.5x tones
y_shift = pyrb.pitch_shift(y, sr, 1.5)
sf.write("analyzed_filepathX105.wav", y_stretch, sr, format='wav')

sound = AudioSegment.from_wav("analyzed_filepathX105.wav")
sound.export("analyzed_filepathX105.mp3", format="mp3")

# Play back at same speed
y_stretch = pyrb.time_stretch(y, sr, 1)
# Play back two smae-tones
y_shift = pyrb.pitch_shift(y, sr, 1)
sf.write("analyzed_filepathXnormal.wav", y_stretch, sr, format='wav')

sound = AudioSegment.from_wav("analyzed_filepathXnormal.wav")
sound.export("analyzed_filepathXnormal.mp3", format="mp3")

**Make Sure to install **

Wave, AudioSegment, FFmpeg, PYRubberBand, Soundfile

To use this Run,

python3 filename.py mp3filename.mp3

Hi, why is y_stretch not passed to pitch_shift function? when you write the result, you seem to use only y_stretch. Could you please explain how it works? — Jun, Sep 22 '21 at 03:08

score 0 · Answer 4 · answered Jul 30 '22 at 10:51

To change the speed of the audio without changing the pitch (or creating chipmunk effect). You can use below code.

from pydub import AudioSegment
from pydub.effects import speedup

audio = AudioSegment.from_mp3(song.mp3)
new_file = speedup(audio,1.5,150)
new_file.export("file.mp3", format="mp3")

How to change audio playback speed using Pydub?

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