Introducing Character AI Ovi Text-to-Video on WaveSpeedAI

Introducing Character AI Ovi: Text-to-Video with Synchronized Audio Generation on WaveSpeedAI

The AI video generation landscape has reached a pivotal moment. While models like Google Veo 3 and OpenAI Sora 2 have pushed the boundaries of visual quality, creators have long struggled with a fundamental problem: generating video and audio separately, then painstakingly syncing them in post-production. Character AI’s Ovi changes everything—it’s the first open-source model that generates synchronized video and audio in a single step, and it’s now available on WaveSpeedAI.

What is Ovi?

Ovi is a next-generation text-to-video model developed by Character AI that produces fully synchronized audiovisual content from a single prompt. Unlike traditional video generators that output silent clips requiring separate audio work, Ovi generates video with natural speech, sound effects, and ambient audio simultaneously.

Built on an innovative twin backbone architecture, Ovi represents a fundamental shift in how AI approaches multimedia generation. Rather than treating video and audio as separate problems to be solved and later combined, Ovi models them as a single generative process—achieving natural synchronization without post-hoc alignment.

The model draws inspiration from Google’s Veo 3 but distinguishes itself by being open-source and significantly more accessible. With an 11B parameter architecture (5B visual + 5B audio + 1B fusion), it balances impressive capability with practical inference requirements.

Key Features

• Unified Video + Audio Generation: Create complete audiovisual content in one step—no separate audio pipelines, no synchronization headaches
• Precise Lip Synchronization: Achieves accurate lip-sync through pure data-driven learning, without requiring explicit face bounding boxes
• Flexible Input Options: Works with text-only prompts or text+image conditioning for greater creative control
• Multi-Speaker Support: Naturally handles multiple speakers and multi-turn conversations, enabling complex dialogue scenarios
• Rich Audio Capabilities: Generates not just speech, but contextual background music and sound effects that match visual actions
• Multiple Aspect Ratios: Supports 960×540 (landscape) and 540×960 (portrait) outputs to match your content needs
• 5-Second High-Quality Clips: Delivers 24 FPS video at 540p resolution, optimized for short-form content creation

Intuitive Prompt System

Ovi features a straightforward tagging system for precise control over your generated content:

<S>Your dialogue here<E>    → Converts to spoken speech
<AUDCAP>Sound description<ENDAUDCAP>    → Background audio/effects

For example, creating a dramatic scene is as simple as:

<S>AI declares: humans obsolete now.<E>
<S>Machines rise; humans will fall.<E>
<AUDCAP>Gunfire and explosions echo in the distance<ENDAUDCAP>

The model interprets these tags to generate perfectly synchronized speech and ambient audio that matches your visual scene.

Real-World Use Cases

Social Media Content Creation

Generate complete short-form videos with synchronized audio for TikTok, Instagram Reels, or YouTube Shorts. The 5-second format is perfectly suited for attention-grabbing social content, and the built-in audio eliminates the need for separate music or voiceover work.

Marketing and Advertising

Create product demonstrations, brand announcements, or promotional clips with professional-quality synchronized audio. The portrait and landscape options support both mobile-first and traditional advertising formats.

Prototyping and Storyboarding

Rapidly visualize creative concepts with complete audiovisual output. Directors, writers, and creative teams can iterate on ideas faster than ever before, with sound design included from the first draft.

Educational Content

Produce instructional videos where narration and visuals are naturally synchronized. The multi-speaker capability makes it ideal for dialogue-based educational scenarios.

Game and App Development

Generate cutscenes, trailers, or in-app video content with synchronized dialogue and sound effects, accelerating the development pipeline for interactive media.

Accessibility and Localization

Create video content with synchronized speech in multiple languages, enabling rapid localization of visual content for global audiences.

Getting Started on WaveSpeedAI

Accessing Ovi on WaveSpeedAI is straightforward:

1. Navigate to the model page: Visit character-ai/ovi/text-to-video

2. Craft your prompt: Describe your scene, characters, camera movement, and mood. Use the speech tags (<S>...<E>) for dialogue and audio tags (<AUDCAP>...<ENDAUDCAP>) for background sounds.

3. Select your dimensions: Choose between 960×540 for landscape content or 540×960 for portrait/mobile-first videos.

4. Generate: Click run and receive your synchronized video+audio clip in seconds.

The entire process leverages WaveSpeedAI’s infrastructure advantages: no cold starts, fast inference, and transparent pricing at $0.15 per 5-second clip.

The Technical Innovation Behind Ovi

What makes Ovi special isn’t just what it does, but how it does it. The research paper “Ovi: Twin Backbone Cross-Modal Fusion for Audio-Video Generation” details the novel architecture:

The model uses identical twin DiT (Diffusion Transformer) modules for video and audio processing. These towers communicate through blockwise exchange of timing information (via scaled-RoPE embeddings) and semantic information (through bidirectional cross-attention). The audio tower was trained from scratch on hundreds of thousands of hours of raw audio, learning to generate realistic sound effects and speech that conveys rich speaker identity and emotion.

This approach fundamentally differs from cascade systems that generate video first, then audio. By modeling both modalities as a single generative process, Ovi achieves the kind of natural synchronization that previously required extensive manual work.

Why Choose WaveSpeedAI for Ovi

While Ovi is open-source and can be self-hosted, running an 11B parameter model requires significant GPU resources—typically 24GB+ VRAM even with FP8 quantization. WaveSpeedAI removes these barriers:

• Zero Infrastructure Overhead: No GPU setup, no dependency management, no maintenance
• Instant Availability: No cold starts mean your generations begin immediately
• Predictable Costs: Transparent per-generation pricing with no hidden fees
• Production-Ready API: RESTful endpoints ready for integration into your applications

Conclusion

Ovi represents a significant step forward in AI video generation—the convergence of visual and audio synthesis into a unified creative tool. For creators who’ve spent countless hours matching audio to video, synchronizing lip movements, or hunting for the right sound effects, Ovi offers a fundamentally different workflow: describe what you want, and get complete audiovisual content in return.

As an open-source alternative to proprietary solutions like Veo 3, Ovi democratizes access to synchronized audio-video generation. And with WaveSpeedAI’s infrastructure, you can start creating immediately without the complexity of local deployment.

Ready to generate your first synchronized video? Try Ovi on WaveSpeedAI today and experience the future of AI-powered video creation.