AI Caption Translator

Pretranslate Udemy lecture transcript cues in batches and show cached translations in sync with video playback.

AI Caption Translator is a personal study helper for Udemy lecture pages that already expose captions and a transcript panel. When you press [Start translation], the extension pauses the current video if it was playing, reads the current lecture's transcript cue text from the Udemy page, and sends only uncached cue batches to the translation provider you selected. Gemini API is the default provider, and OpenAI API is available as an alternative. After pretranslation is ready, the extension displays cached transcript matches in sync with the visible video captions and resumes playback only when preparation succeeds. Request-saving behavior: - No individual-caption API request is sent during playback. - Cached cue translations are reused locally. - Transcript cue batches are paced with model-aware request intervals. - Gemini daily request limits are checked before provider calls. - Missing or unmatched cues show a status message instead of triggering an automatic fallback request. Data handling: - API keys and settings are stored in Chrome storage. - Translation cache entries stay in the user's browser profile. - Current-lecture transcript cue batches can be sent to the selected Gemini or OpenAI endpoint only after the user starts translation. - The extension does not operate a developer backend and does not sell user data. Limitations: - Udemy captions must be enabled in the video player. - Udemy must expose a transcript panel for batch pretranslation. - Provider API limits, provider data handling, and billing are controlled by the user's selected API provider and account. This extension does not download video or audio files, crawl full courses, redistribute course content, record the screen, or claim affiliation with Udemy.