Audio Overlay Script

This Python script overlays a speech/lyrics audio file with a background music file, ensuring the background music doesn't overpower the speech. The script uses pydub for audio manipulation and requires ffmpeg for processing audio files.

Features

• Overlays a speech/lyrics audio file with background music.
• Allows specifying how much quieter the music should be compared to the speech.
• Allows selecting specific parts of both the speech and music files for the overlay.
• Ensures the music does not overpower the speech by adjusting the volume of the music.
• Supports padding with silence if the music is shorter than the speech.
• Allows specifying the start time for overlaying the music within both the speech and music files.
• Allows specifying how long the music continues after the speech ends.
• Supports fade-in and fade-out effects with customizable durations.
• Generates a uniquely named output file using the current date and time to avoid conflicts.

Requirements

• Python 3.6 or higher
• pydub
• ffmpeg

Installation

1. Install pydub using pip:

   pip install pydub

2. Install ffmpeg and ensure it is added to your system's PATH. Follow the installation instructions from the FFmpeg website.

Usage

1. Clone or download the repository.

2. Modify the main() function in the script to set the correct input paths, output directory, and overlay parameters.

3. Run the script:

   python audio_overlay.py

Example Configuration

def main():
    # Define input paths
    speech_path = "path/to/speech.mp3"
    music_path = "path/to/music.mp3"
    current_time = datetime.now().strftime("%Y%m%d%H%M%S")
    
    # Define output dir
    output_dir = "output_audio"
    os.makedirs(output_dir, exist_ok=True)
    
    # Generate the output path
    output_path = os.path.join(output_dir, f"combined_audio_{current_time}.mp3")
    
    # Parameters for overlay
    music_volume_adjustment = -10  # Music will be 10 dB quieter than speech
    speech_start = 0  # Start of the speech portion to use (in seconds)
    speech_end = None  # End of the speech portion to use (in seconds), None for full length
    music_start = 0  # Start of the music portion to use (in seconds)
    music_end = None  # End of the music portion to use (in seconds), None for full length
    speech_overlay_start = 0  # When to start the overlay in the speech file (in seconds)
    music_overlay_start = 0  # When to start the overlay in the music file (in seconds)
    music_continue_after_speech = 5  # How long the music continues after the speech ends (in seconds)
    fade_in_duration = 3  # Fade-in duration (in seconds)
    fade_out_duration = 3  # Fade-out duration (in seconds)
    
    # Overlay the audio
    overlay_audio(speech_path, music_path, output_path, music_volume_adjustment, 
                  speech_start, speech_end, music_start, music_end, 
                  speech_overlay_start, music_overlay_start, 
                  music_continue_after_speech, fade_in_duration, fade_out_duration)

if __name__ == "__main__":
    main()

Functions

• adjust_background_music(speech, music, music_volume_adjustment): Adjusts the volume of the background music to ensure it doesn't overpower the speech.
• apply_fades(audio, fade_in_duration=0, fade_out_duration=0): Applies fade-in and fade-out effects to the audio.
• overlay_audio(speech_path, music_path, output_path, music_volume_adjustment=-10, speech_start=0, speech_end=None, music_start=0, music_end=None, speech_overlay_start=0, music_overlay_start=0, music_continue_after_speech=0, fade_in_duration=0, fade_out_duration=0): Overlays a speech/lyrics audio file with background music.
• main(): Sets the input paths, output directory, and overlay parameters, and calls the overlay_audio function.

License

This project is licensed under the MIT License. See the LICENSE file for details.

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Notes

• Ensure ffmpeg is installed and accessible via the system's PATH.
• Adjust the speech_path, music_path, output_dir, and other parameters as necessary.
• The script generates a uniquely named output file based on the current date and time to avoid file name conflicts.