movie-subtitles 0.1.1

Command line tool that turns a video or audio file into a translated .srt file, and optionally into a dubbed video with a synthesised translated audio track.

Installation

Published on PyPI as movie-subtitles.

# Run without installing (recommended)
uvx movie-subtitles --input clip.mp4

# Install as a tool
uv tool install movie-subtitles

# Or with pip
pip install movie-subtitles

# Latest from git instead of the release on PyPI
uvx --from git+https://github.com/mathiasesn/movie-subtitles.git movie-subtitles --input clip.mp4

# Develop locally
git clone https://github.com/mathiasesn/movie-subtitles.git
cd movie-subtitles && uv sync && uv run movie-subtitles --help

Requires Python >= 3.10 and uv. ffmpeg must be on PATH for --dub; the plain .srt path and --managed do not need it.

Engines

The pipeline has three stages, each backed by a vendor you choose independently:

--engine is a shorthand that sets all three at once; per-stage flags always override it.

--engine elevenlabs alone errors on purpose. ElevenLabs has no standalone text-translation endpoint — translation exists only bundled inside the Dubbing job (--managed) — so there is nothing honest for the shorthand to resolve the translation stage to. Pass --translation-engine {anthropic,openai,local} explicitly.

Engine values name vendors, not pipelines. An earlier version used --translation-engine elevenlabs; that value no longer exists, and its replacement is --translation-engine anthropic, since the call was always Claude.

Known limitation: --asr-engine openai

whisper-1's segment timestamps degrade to uniform 1.000s spans on music-heavy or dialogue-sparse audio (observed on a movie trailer), which corrupts both .srt cue timings and dub slots. Prefer --asr-engine elevenlabs on such material.

API keys

--engine local needs no keys and stays fully offline after the first model download. Everything else reads one or more of:

export ELEVENLABS_API_KEY="..."   # --asr-engine/--tts-engine elevenlabs, --managed
export ANTHROPIC_API_KEY="..."    # --translation-engine anthropic
export OPENAI_API_KEY="..."       # any stage set to openai

Or copy .env.example to .env and fill it in — .env is gitignored and loaded on startup, searching upward from the directory you run in. Exported variables take precedence. A missing key exits with a one-line error naming the variable, no traceback.

Usage

# Local, offline, .srt only
movie-subtitles --input clip.mp4

# ElevenLabs ASR + Claude translation, .srt only
movie-subtitles --input clip.mp4 --engine elevenlabs --translation-engine anthropic

# ...and dubbed into clip.dubbed.mp4 (needs ffmpeg)
movie-subtitles --input clip.mp4 --engine elevenlabs --translation-engine anthropic --dub

# OpenAI end to end, .srt only / dubbed
movie-subtitles --input clip.mp4 --engine openai
movie-subtitles --input clip.mp4 --engine openai --dub

# Mixed vendors — Scribe ASR, OpenAI translation and voice
movie-subtitles --input clip.mp4 --asr-engine elevenlabs --translation-engine openai --tts-engine openai --dub

# Managed ElevenLabs Dubbing job — no local ASR/MT/TTS code runs at all
movie-subtitles --input clip.mp4 --managed

Other flags: --audio-lang, --srt-lang, --whisper-model, --mt-model. Run movie-subtitles --help for the full list.

Dubbing notes

• --dub replaces the original audio track, it does not mix with it. Only the synthesised track is mapped onto the source video; the original spoken audio is dropped.

• --dub and --managed are mutually exclusive. --managed replaces the whole pipeline with a single hosted job.

• --dub fails if TTS resolves to something unusable, e.g. plain --engine local --dub, since local has no TTS backend:

  [ERROR][cli] --dub requires a usable TTS engine, but it resolved to 'local'. Pass --tts-engine {elevenlabs,openai} explicitly.
  

• --translation-engine local with --dub is allowed but warns. MADLAD400 ignores the length budget, so timing-drift fitting degrades to TTS-rate-only.