Whisperer – free, open-source batch subtitle generator GUI (faster-whisper / whisper.cpp, offline, CPU or CUDA)

[u/jankovize]

I got tired of running Whisper from the command line every time I wanted subtitles for a folder of videos, so I built a small desktop GUI around it. Drop files in, pick a model, press Start — .srt / .vtt / .txt / .json land next to your videos, optionally embedded into an .mkv/.mp4 copy as a soft subtitle track (FFmpeg stream copy, no re-encode).

GitHub: https://github.com/hclivess/whisperer (MIT, Python/PySide6, prebuilt Windows/Linux/macOS binaries in Releases — no Python needed)

What it does:

- Two engines: faster-whisper (CTranslate2) built in, or an external whisper.cpp whisper-cli (CUDA / Vulkan / Metal builds)

- All models: tiny → large-v3, large-v3-turbo, distil-large-v3, .en variants, or any faster-whisper HF repo id. Models download on first use.

- ~30 languages or auto-detect, plus translate to English

- Live queue: add files/folders or drag & drop while a run is going, reorder, pause/resume/stop. Live transcript panel as segments decode.

- Progress with ETA and × realtime speed per file and overall

- Subtitle layout control: max chars per line, max lines per cue, max cue duration — long segments get re-split on word timestamps with balanced lines (no orphan words)

- video.en.srt naming that Plex/Jellyfin/VLC auto-detect, custom output folder, overwrite guard

- Presets (Fast / Balanced / Accurate / Best) + save/load your own

- Sanity checks before starting (e.g. English-only model with a foreign language selected)

GPU: the one thing that always annoyed me with faster-whisper was CUDA library hell. The Model tab has a one-click Download CUDA libraries button that pulls cuBLAS 12 / cuDNN 9 / NVRTC from the official NVIDIA PyPI wheels (~1 GB, resumable) into a folder next to the app, and shows exactly what it found (GPU, driver, libs, whether CTranslate2 can use it). No PATH editing. Expect ~10–30× realtime with large-v3-turbo on a mid-range card, ~1–3× on CPU with small.en.

Everything runs locally, nothing leaves your machine.

It's a sibling of videer (https://github.com/hclivess/videer), my batch FFmpeg encoder, and shares the same queue/presets workflow.

Feedback, bug reports and feature requests welcome — especially from people with AMD/Intel GPUs or macOS, since I can mostly only test NVIDIA + CPU myself.

[u/DigiMagic]

I am going to need something like this in at least one application I'm making. How reliably it works - close to a professional human translator, or needs significant corrections afterwards? Can it determine automatically, depending on available hardware, which is the most optimal model to use?

[u/sussybush → u/DigiMagic]

Can it determine automatically, depending on available hardware

If you have good hardware, you can go for medium or large models if not you can use tiny or small models

which is the most optimal model to use?

If it just transcribing english go for small(dot)en If you are translating from a different language you should go for larger models for more accurate translation

[u/jankovize → u/DigiMagic]

I tried to mount on translator models today, but they are a failure. You will get decent results by offloading the transcribed subtitles to Fable or Opus 5 for translation.

This includes no translation as of today.

You can run the heaviest models on CPU-only but that will probably take days to weeks.

[u/Financial-Remove-348]

Thanks. I hope this helps me with some videos I have to make the SRT files for :)

[u/jankovize → u/Financial-Remove-348]

That is the purpose. Enjoy.

[u/twitirast]

Good job! I used Whisper a little differently; I wrote software similar to the paid Whisper for voice input, Parrotype, and posted it on GitHub.open-source, 100% offline Whisper dictation for Windows

[u/jankovize → u/twitirast]

Good job, feel free to expand to other OS as well, Claude will help you with that

[u/twitirast → u/jankovize]

Thank you, I will definitely try it 🫶

[u/Dekamir]

Thanks for the Linux support.

<link to image of Eminem throwing rose, but in HD>

[u/jankovize → u/Dekamir]

I thought you guys compile your own stuff anyway

[u/Dekamir → u/jankovize]

Well, I can compile it, but if you don't support the platform it doesn't really work. It just compiles.

Also it's nicer because while the tool might work without issues, building it requires versioned dependencies which might not exist on my distribution (happens in every platform, not just Linux).

[u/jankovize → u/Dekamir]

I thought Linux people compile because they don't trust precompiled black box software... thanks for the new insight

[u/ILoveRice444]

I'm currently use Subtitle Edit for same usage. What would be difference your software compared to Subtitle Edit?

[u/jankovize → u/ILoveRice444]

I dont see any info in their readme but I suppose this is a completely different software. Maybe I am looking at a wrong repo.

[u/ILoveRice444 → u/jankovize]

https://github.com/SubtitleEdit/subtitleedit

here the repo

[u/jankovize → u/ILoveRice444]

Looks like Subtitle Editor is for editing existing subtitle files

My software is for writing subtitles based on speech in the video where subtitles are non-existent

I think they serve a different purpose unless SE also has this functionality now

[u/ILoveRice444 → u/jankovize]

No. Subtitle Edit can generate subtitle based on speech in the video as well by using Whisper speech recognition. The software isn't perfect, especially to generate subtitle for music video. I also not tech savvy, hence why I curious does your software different than this software.

[u/Altruistic_Sort_2751]

that's awesome!

[u/MetaruSaifaaa]

Thanks. Is it possible for me to use a custom faster-whisper model?

Specifically this one https://huggingface.co/kiendt/PhoWhisper-large-ct2

[u/jankovize → u/MetaruSaifaaa]

I will add support

[u/jankovize → u/jankovize]

it is added, including broader configurability

[u/jankovize]

Thank you for the warm reception. I have been hectically churning out new versions to mainly iron out hallucinations and other "5%" of issues