REVERSE_MP3

The Python program featured in this tutorial generates a reversed-playing version of some input audio file (in MP3 format).

In the words of ChatGPT-5.2,”The program takes a specific MP3 audio file as input, decodes its compressed sound data into an in-memory representation, reverses the temporal order of that audio so that the final sound becomes the first sound and the first sound becomes the final sound, and then writes this reversed sequence out as a new MP3 file at a user-defined location. No attempt is made to reinterpret, analyze, or modify the content of the audio beyond this strict reversal; the operation is mechanical and deterministic, transforming the input file into a time-inverted counterpart whose existence depends entirely on the presence and integrity of the original file. In this way, the program functions as a one-directional transformer of stored sound, turning a forward-moving recording into a reversed artifact that preserves structure while inverting order, suitable for archival, experimental, or purely observational purposes.”

For the sake of making the media files linked to by this web page easily saveable to the WayBack Machine, karbytes embedded the MP3 files inside of MP4 files (with just the color black as the visual component of each of those video files). To convert those MP4 files back to MP3 files, use the Python script featured on the following software engineering tutorial web page:

https://karbytesforlifeblog.wordpress.com/mp4_to_mp3_converter/).

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SOFTWARE_APPLICATION_COMPONENTS

python_source_file: https://raw.githubusercontent.com/karlinarayberinger/KARLINA_OBJECT_extension_pack_51/main/reverse_mp3.py

input_audio_(source_video): https://raw.githubusercontent.com/karlinarayberinger/KARLINA_OBJECT_extension_pack_51/main/blackened_karbytes_message_04jan2026_p0.mp4

output_audio_(source_video): https://raw.githubusercontent.com/karlinarayberinger/KARLINA_OBJECT_extension_pack_51/main/blackened_karbytes_message_04jan2026_p0_[reversed_audio].mp4

PROGRAM_INTERPRETATION_AND_EXECUTION

STEP_0: Copy and paste the Python source code into a new text editor document and save that document as the following file name:

reverse_mp3.py

STEP_1: Open a Unix command line terminal application and set the current directory to wherever the Python program file is located on the local machine (e.g. Desktop).

cd Desktop

STEP_2: Run the program by entering the following command:

python3 reverse_mp3.py

STEP_3: If the program interpretation command does not work, then use the following commands (in top-down order) to install the Python interpreter and, also, the requisite Python library files for reverse_mp3.py:

# Python interpreter
sudo apt update
sudo apt install python3

# multi-media framework
sudo apt install ffmpeg

STEP_4: Observe program results on the command line terminal and in the output file.

PROGRAM_SOURCE_CODE

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python_source_file: https://raw.githubusercontent.com/karlinarayberinger/KARLINA_OBJECT_extension_pack_51/main/reverse_mp3.py

#########################################################################################
# file: reverse_mp3.py
# type: Python
# date: 05_JANUARY_2026
# author: karbytes
# license: PUBLIC_DOMAIN 
#########################################################################################

"""
This Python program reverses the playback order of a specific MP3 file.

The input file path and output file path are explicitly defined
inside this source code file to ensure reproducibility and clarity.

The program performs the following steps:

1. Loads the input MP3 file from disk
2. Decodes the MP3 into raw audio samples
3. Reverses the order of those samples
4. Re-encodes the reversed samples as a new MP3 file
"""

import os
from pydub import AudioSegment

# -------------------------------------------------
# user-defined file paths (edit these as needed)
# -------------------------------------------------
input_mp3_path = "input_audio.mp3"
output_mp3_path = "input_audio_[reversed].mp3"

# -------------------------------------------------
# verify input file exists
# -------------------------------------------------
print("Input MP3 file path:")
print(input_mp3_path)

if not os.path.isfile(input_mp3_path):
    print("Error: input MP3 file does not exist.")
    raise SystemExit(1)

# -------------------------------------------------
# load MP3 file into memory
# -------------------------------------------------
print("Loading MP3 file into memory...")

audio_data = AudioSegment.from_file(
    input_mp3_path,
    format="mp3"
)

# -------------------------------------------------
# reverse audio samples
# -------------------------------------------------
print("Reversing audio samples...")

reversed_audio_data = audio_data.reverse()

# -------------------------------------------------
# write reversed audio to output file
# -------------------------------------------------
print("Writing reversed MP3 file:")
print(output_mp3_path)

reversed_audio_data.export(
    output_mp3_path,
    format="mp3",
    bitrate="192k"
)

# -------------------------------------------------
# completion message
# -------------------------------------------------
print("Done.")
print("Reversed MP3 file successfully created.")

This web page was last updated on 05_JANUARY_2026. The content displayed on this web page is licensed as PUBLIC_DOMAIN intellectual property.