What is Simul Subtitle?

A floating-subtitle app by KorenKrita for Japanese and English video and livestreams on Android, macOS, and Windows: local offline speech recognition, BYOK translation through an OpenAI-compatible endpoint, and subtitle windows that sit above any player.

Two optional TypeSafe Jev helpers act as structured judgments: one decides whether a speaker has finished a sentence before the draft is finalised, and one checks a finished translation for mistranslation before a single re-translation. Both are off by default.

Do I need Jev or an API key to use it?

You need a translation endpoint, and the README suggests any OpenAI-compatible service, but not Jev. The repository's Jev notes name a free default channel that needs no key, plus official and OpenRouter routes for paid use; the helpers degrade to normal behavior on any failure.

Does my audio ever leave the device?

No: the README says recognition uses built-in ReazonSpeech and Silero VAD models (~78 MB) and audio never leaves the device. Only the recognized source text and its translation are sent to the endpoints you configure.

How do I start using it?

Three steps from the README: enter an OpenAI-compatible address, model ID, and key; grant platform permissions (Android records app audio and shows overlays, macOS records system sound, Windows needs none); then choose the source language and start.

Which platforms and players are supported?

Android, macOS, and Windows. Subtitle windows float over Bilibili, YouTube, Twitch, browsers, and local players; phones record the target app's audio directly, while desktop builds listen to system audio output without a microphone.

What does it cost and what licence does it use?

The repo is MIT. Translation is billed by whichever provider you connect, and the repository's Jev notes estimate roughly $0.04 per hour with the paid channel enabled. Metadata shows 59 stars, created 2026-10-11, last pushed 2026-10-16.

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Simul Subtitle

Floating real-time translated subtitles for Japanese and English video and livestreams on Android, macOS, and Windows: speech recognition runs fully offline with bundled models, translation uses your own OpenAI-compatible endpoint, and optional TypeSafe Jev helpers refine the result.

See highlights Open github.com

Stars: 63
Language: Kotlin
License: MIT
Reading time: 3 min
Published by: Community
Author: KorenKrita
Last verified: Oct 2026

korenkrita/simul-subtitle

User repository on GitHub

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日语、英语视频与直播实时同传悬浮字幕（Android / macOS / Windows）｜本地离线语音识别 · 自备 LLM 翻译（BYOK）

Forks: 4
Last pushed: Updated Oct 2026

Repo stats from the GitHub API, cached Oct 2026.

Tagscommunity github subtitles translation offline

Works forJev for Classification Jev for Verification

Used inJev for Media & Entertainment

Platforms: macOS OpenRouter
Capabilities: Open sourceRuns locallyRequires API key

Highlights

README: subtitles float above any player — Bilibili, YouTube, Twitch, browsers, or local video — on Android, macOS, and Windows, no root or ADB required.
Speech recognition is fully local: bundled ReazonSpeech ASR and Silero VAD models (~78 MB) ship in the app, and the README states audio never leaves the device.
Translation is BYOK: any OpenAI-compatible endpoint such as DeepSeek, Qwen, or OpenRouter, saved profiles, and auto-detection that disables thinking mode.
Optional, off-by-default TypeSafe Jev helpers: one judges sentence boundaries, another flags mistranslations for one re-translation; failures fall back.
MIT Kotlin repo with Chinese and English READMEs: 59 stars, 3 forks, created 2026-10-11, last pushed 2026-10-16, plus scenario presets and custom glossaries.

Watch out

The digest's README excerpt, reviewed 2026-10-17, truncates mid-document before the optional Jev section, so those details — two off-by-default helpers, channel options, and cost notes — were verified in the repository README and docs/jev.md the same day. No benchmarks, hardware minimums, or install commands beyond the Releases page appear in the excerpt, and translation costs depend on the provider you connect.

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Simul Subtitle

Highlights

Questions about this entry

What is Simul Subtitle?

How does it use Jev?

Do I need Jev or an API key to use it?

Does my audio ever leave the device?

How do I start using it?

Which platforms and players are supported?

What does it cost and what licence does it use?

More Jev resources like this

From the Jev guides

From the Jev AI model community