HunyuanVideo — Tencent’s 13B‑Parameter Open‑Source AI Video (Research Overview)
Download printable cheat-sheet (CC-BY 4.0)25 Jul 2025, 00:00 Z
TL;DR
HunyuanVideo (reported ~13B params) introduces dual‑stream fusion and video‑to‑audio synthesis in public materials.
It is open‑sourced (see repo/license); performance depends on setup and prompts.
Use official docs/papers for benchmarks and compare responsibly.
1 The open-source video breakthrough we've been waiting for
December 3rd, 2024 introduced HunyuanVideo — a ~13‑billion parameter open‑source project. Competitive positioning vs. closed‑source models depends on evaluation scope and criteria.
1.1 By the numbers
| Metric | HunyuanVideo (reported) |
| Model size | ~13B parameters |
| Open source | Repo + weights published (see refs) |
Benchmarks vary by prompt set, settings and methodology; consult the paper/repo.
2 Technical architecture that changes everything
2.1 Dual-stream to single-stream fusion
HunyuanVideo's secret weapon is its dual-stream architecture that processes video and text tokens independently before fusing them:
Phase 1: Dual-Stream Processing
- Video tokens → Independent Transformer blocks
- Text tokens → Separate modulation mechanisms
- Result → Zero cross-contamination during feature learning
Phase 2: Single-Stream Fusion
- Input → Concatenated video + text tokens
- Processing → Joint Transformer processing
- Output → Multimodal information fusion
2.2 Revolutionary video-to-audio synthesis
The V2A (Video-to-Audio) module automatically analyzes video content and generates synchronized:
- Footstep audio matching character movement
- Ambient soundscapes fitting the environment
- Background music aligned with scene emotion