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ZipCaptions is a browser-native, open-source application that produces live closed-captions and transcripts from audio sources. It runs as a Progressive Web App and focuses on client-side captioning with optional cloud-backed AI captioning for higher accuracy.

Key Features

• In-browser real-time speech-to-text captioning (browser engine) without mandatory server processing.
• Optional cloud AI captions using Azure Cognitive Services for improved accuracy (paid feature).
• PWA installable experience; supports persistent overlay and browser integrations for live streams and broadcasts.
• Streaming/broadcast support with joinable caption streams and direct integration guidance for OBS, vMix, and other production tools.
• Local transcript storage with export options (SRT, VTT, TXT) for use with video or documentation workflows.
• Multiple languages and dialect selection in settings to improve recognition quality.

Use Cases

• Live event accessibility: provide open or closed captions for conferences, worship services, classrooms, and streamed events.
• Broadcast/production workflows: feed live captions into OBS, vMix, or browser-source panels for real-time on-screen titles.
• Post-session captioning: record and export session transcripts in subtitle formats for video publishing and archiving.

Limitations and Considerations

• Cloud AI captions require Azure Cognitive Services and are restricted to paying supporters; browser engine remains the free/default option.
• Browser and OS differences can affect microphone access and caption reliability (known issues documented for specific Chrome versions and some mobile builds).
• Transcripts are stored locally per device by design; syncing across devices requires manual export/import.

ZipCaptions prioritizes accessibility-first, client-side captioning with optional cloud AI for higher accuracy. It is intended for event captioning and production integration where low-cost, privacy-conscious captioning is required.