How to get the duration of audio in Python?

Getting the duration of audio files is a common task in audio processing applications. Python offers several libraries to accomplish this, each with its own advantages for different use cases.

The audio duration refers to the length of time an audio file plays, typically measured in seconds. This value depends on the audio file's properties like sample rate, number of frames, and channels.

Algorithm

The general process for calculating audio duration involves ?

• Import the appropriate audio processing library

• Load the audio file

• Extract audio properties (sample rate, frames, channels)

• Calculate duration using: duration = frames / sample_rate

Using the wave Library

The wave library is built into Python and works specifically with WAV files ?

import wave

def get_duration_wave(file_path):
    with wave.open(file_path, 'r') as audio_file:
        frame_rate = audio_file.getframerate()
        n_frames = audio_file.getnframes()
        duration = n_frames / float(frame_rate)
        return duration

# Simulate reading a 10-second WAV file
print("Using wave library:")
print("Frame rate: 44100 Hz")
print("Number of frames: 441000")
duration = 441000 / 44100.0
print(f"Duration: {duration:.2f} seconds")

Using wave library:
Frame rate: 44100 Hz
Number of frames: 441000
Duration: 10.00 seconds

Using the pydub Library

Pydub supports multiple audio formats and provides a simple interface. Install with pip install pydub ?

from pydub import AudioSegment

def get_duration_pydub(file_path):
    audio_file = AudioSegment.from_file(file_path)
    duration = audio_file.duration_seconds
    return duration

file_path = 'example.wav'
duration = get_duration_pydub(file_path)
print(f"Duration: {duration:.2f} seconds")

Duration: 10.00 seconds

Using the librosa Library

Librosa is powerful for music and audio analysis. Install with pip install librosa ?

import librosa

def get_duration_librosa(file_path):
    audio_data, sample_rate = librosa.load(file_path)
    duration = librosa.get_duration(y=audio_data, sr=sample_rate)
    return duration

file_path = 'example.wav'
duration = get_duration_librosa(file_path)
print(f"Duration: {duration:.2f} seconds")

Duration: 10.00 seconds

Using ffmpeg-python

FFmpeg handles virtually any audio/video format. Install with pip install ffmpeg-python ?

import ffmpeg

def get_duration_ffmpeg(file_path):
    probe = ffmpeg.probe(file_path)
    stream = next((stream for stream in probe['streams'] 
                  if stream['codec_type'] == 'audio'), None)
    duration = float(stream['duration'])
    return duration

file_path = 'example.wav'
duration = get_duration_ffmpeg(file_path)
print(f"Duration: {duration:.2f} seconds")

Duration: 10.00 seconds

Comparison

Conclusion

Use wave for simple WAV files, pydub for general audio tasks, librosa for music analysis, or ffmpeg-python for maximum format support. Each library provides reliable methods to calculate audio duration in Python.