awesome-python/website/data/category_intros/audio-video-processing.md

Each job has its own pick: librosa is the Python audio processing library for music analysis, MoviePy edits video from a script, and Mutagen tags audio files.

How to choose:

• Cutting, joining, and fading audio files: pydub
• Music and audio analysis: librosa
• Editing video or making GIFs from a script: MoviePy
• Real-time video from cameras and network streams: VidGear
• Reading and writing tags across formats: Mutagen
• Reading tags only: tinytag
• Tagging and organizing your music collection: beets

pydub gives you a simple, high-level interface to cut, join, and fade audio. It opens and saves WAV files in pure Python, but other formats like MP3 need FFmpeg, so install FFmpeg with it. An AudioSegment is immutable: every operation returns a new one, so you can chain them, and every length and position is in milliseconds.

librosa gives you the foundational algorithms and tools for music information retrieval. By default, librosa.load resamples the signal and mixes stereo down to mono, and those defaults suit most analysis tasks; pass sr=None to keep the file's own sampling rate. When you need more control than load gives you, such as writing files, its docs recommend using its audio I/O backend directly.

MoviePy is for automating video editing: processing many videos, composing them in complicated ways, or making videos and GIFs on a web server. A script loads clips, modifies them, puts them together, and writes the result. Modifying a clip returns a new clip and leaves the original alone, and the computation happens at the final render. Open file clips in a with block, or call close() when you're done, since each one holds a subprocess and a lock on the file. MoviePy can't stream video. For frame-by-frame analysis, its docs send you to a computer vision library.

VidGear is a framework for real-time media applications built on OpenCV and FFmpeg. All its APIs keep OpenCV's coding syntax. Each task has its own gear: CamGear reads cameras, network streams, and streaming sites in multiple threads. WriteGear writes frames to a video file or network stream, and StreamGear transcodes video into adaptive streaming formats. Install OpenCV first, since the core functions need it.

Mutagen reads and writes tags with roughly the same API across all tag formats. mutagen.File guesses the file type. ID3 tags in MP3 files are highly structured; for common keys, use the simpler EasyID3 interface. Mutagen is licensed under GPL-2.0-or-later; if you only read tags, MIT-licensed tinytag avoids that.

tinytag only reads metadata, and writing support will not be added: its README points you to Mutagen for that. It's pure Python with no dependencies and gives you the same API for every format. TinyTag.get() returns an object with attributes like artist and duration.

beets is a command-line music library manager, not a library you import: it catalogs your collection and improves its metadata as it goes. Install it as a standalone tool, isolated from your system Python and other packages. beet import can modify and move your files, so back up first and import a few albums at a time. Plugins add commands, fetch extra data during import, and add metadata sources.

FFmpeg sits under most of these projects: pydub needs it for any format other than WAV, MoviePy runs on it, and VidGear's WriteGear and StreamGear wrap it. When you only want to convert a video file or turn images into a movie, call FFmpeg directly. MoviePy's own docs say it's faster and uses less memory than going through MoviePy.