simul-subtitle

What is simul-subtitle

A real-time video and live streaming subtitle tool supporting Japanese and English, with floating subtitles. It runs on Android, macOS and Windows, uses local offline speech recognition, and supports user-provided LLMs for translation (BYOK).

Key features

• Real-time subtitles for Japanese and English videos and live streams, with floating display that can sit above any player or streaming software
• Uses local offline speech recognition with built-in ReazonSpeech and Silero VAD models; audio never leaves the device
• Supports user-provided OpenAI-compatible LLM endpoints for translation, with the ability to save multiple configurations and automatically disable reasoning mode
• Offers two subtitle output modes (streaming or after speech), supports any target language as well as contextual background and terminology lists
• The floating window supports dragging, resizing, position locking, font size and transparency adjustment

Who it is for

Suitable for users who need to watch Japanese or English videos and live streams in real time, especially when using various players or streaming software on Android, macOS or Windows.

How to get started

1. Go to the GitHub Releases page and download the installation package for your platform (Android / macOS / Windows)
2. Android users install the APK and grant audio recording and floating window permissions; macOS users allow system audio recording on first use
3. Open the app, go to Settings → Translation, enter the OpenAI-compatible endpoint address, model ID and API key, then test the connection
4. On the home screen select the source language (Japanese or English), click Start Subtitles, then on mobile choose the target app or on desktop listen to system audio directly

Compiled from public descriptions on the tool's official website / README / launch page. Pricing and user numbers have not been verified; please check the official website. Some sections were drafted with AI assistance. Written in Chinese and English; other languages are machine-translated.