ByteDance's SeedRealtime runs full-duplex audio and video - simultaneously

ByteDance launched SeedRealtime, a full-duplex audio-video model for real-time AI interaction. Unlike Seedance (long-form video generation), this is conversational AI that listens and speaks at the same time - with live video input.

In plain terms: ByteDance released an AI model that processes audio and video input and output at the same time, with no switching between listening and speaking modes. It's the architecture real-time conversation actually requires.

The fact

ByteDance launched SeedRealtime, a full-duplex audio-visual model for real-time AI interaction, according to Tech in Asia. Full-duplex means simultaneous bidirectional streaming: input and output audio and video run in parallel rather than alternating. This is distinct from Seedance (ByteDance's long-form video generation model) - SeedRealtime targets conversational and live-interaction use cases.

Our take

Full-duplex is the hard part. Most voice AI systems are half-duplex: they accept input, generate a response, then switch back to listening. The latency and interruption awkwardness in current voice assistants comes directly from this architecture. SeedRealtime enters a space where OpenAI (GPT-4o Advanced Voice), Google (Gemini Live), and ElevenLabs have built early positions - but adds multimodal video input, which none of those support natively in real-time. The commercial use cases are clear: live translation, real-time customer service, AI companion apps. The competitive signal is clearer: ByteDance is not conceding the real-time multimodal layer to US labs.

What to watch

Latency benchmarks and API pricing at scale. Full-duplex is achievable in a demo; maintaining it cheaply across concurrent sessions at production scale is the actual engineering challenge.