Missing Semester: Lecture Videos

This repository contains the msv package: a small DSL over ffmpeg-python for producing lecture videos for Missing Semester, along with the per-lecture rendering scripts.

Installation

The package uses uv.

For local development, uv sync in a clone of this repo will set up the environment.

If you want to use the DSL from outside the package, you can install it directly from GitHub (this package is not published to PyPI):

uv add git+https://github.com/missing-semester/videos

Library

The DSL lives in msv.lib. A minimal example:

from msv.lib import Audio, Clip, Fullscreen, Multitrack

video = Fullscreen("raw.mp4")
audio = Audio("raw.mp4")
Multitrack([Clip(video, start="00:30", end="01:00")], audio).render("out.mp4")

See src/msv/lectures/ for many more examples.

Console scripts

Installing the package provides the following commands:

• msv-sync-audio: Useful for syncing an audio and a video track.
• msv-sync-video: 2x2 tile of synced video streams. Useful for finding audio/video offsets across multi-camera recordings.
• msv-normalize-sbv: split long lines in .sbv caption files to YouTube-ish widths.
• msv-render-lecture [year] [number] [directory]: render a specific Missing Semester lecture, e.g. msv-render-lecture 2026 1 /path/to/raw/footage.

You can also run these without installing the package with uv run [command name].

Development

uv run mypy .          # type-check
uv run ruff check      # lint
uv run ruff format     # format

License

Copyright (c) Anish Athalye, Jose Javier, and Jon Gjengset. Released under the MIT License. See LICENSE.md for details.