Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

"speed" effect does not work

See original GitHub issue

To reproduce:

filename = "test.wav"

effect = torchaudio.sox_effects.SoxEffectsChain()
effect.set_input_file(filename)
effect.append_effect_to_chain("speed", 1.0)
x,sr = effect.sox_build_flow_effects()
x.shape

effect = torchaudio.sox_effects.SoxEffectsChain()
effect.set_input_file(filename)
effect.append_effect_to_chain("speed", 2.0)
x,sr = effect.sox_build_flow_effects()
x.shape

x.shape will be the same for both.

The “tempo” effect does work, though. Weird, because these two effects have the same interface in SoX.

Issue Analytics

State:
Created 4 years ago
Comments:9 (7 by maintainers)

Top GitHub Comments

1reaction

mthrokcommented, Nov 3, 2020

The SoxEffectChain implementation is removed from torchaudio in #977 and the replacement implementation can handle this in the similar manner. (you still need to add "rate", but it is documented clearly https://pytorch.org/audio/0.7/sox_effects.html#applying-effects-on-tensor

import torchaudio

data, sr = torchaudio.sox_effects.apply_effects_file('test/torchaudio_unittest/assets/sinewave.wav', [['speed', '1.0'], ['rate', '16000']])
print(data.shape, sr)


data, sr = torchaudio.sox_effects.apply_effects_file('test/torchaudio_unittest/assets/sinewave.wav', [['speed', '2.0'], ['rate', '16000']])
print(data.shape, sr)

torch.Size([1, 64000]) 16000
torch.Size([1, 32000]) 16000

I am closing this issue, but @lorenlugosch if you are still experiencing the error with the latest torchaudio, let us know.

1reaction

engineerchuancommented, Sep 17, 2019

Hi Loren,

Can you try adding “rate” as well at the very end?

filename = "test.wav"
si, _ = torchaudio.info(filename )

effect = torchaudio.sox_effects.SoxEffectsChain()
effect.set_input_file(filename)
effect.append_effect_to_chain("speed", 1.0)
effect.append_effect_to_chain("rate", si.rate)
x,sr = effect.sox_build_flow_effects()
x.shape

effect = torchaudio.sox_effects.SoxEffectsChain()
effect.set_input_file(filename)
effect.append_effect_to_chain("speed", 2.0)
effect.append_effect_to_chain("rate", si.rate)
x,sr = effect.sox_build_flow_effects()
x.shape

I believe sox command line as a convenience layer that automatically adds the rate, but this is not in the C interface. This should be a workaround.