Character.AI Launches AvatarFX for Expressive AI Video Generation

Character.AI has unveiled AvatarFX, a next-generation video generation model capable of animating images into highly realistic, emotionally expressive videos. Built by Character.AI’s Multimodal team, AvatarFX is designed to create videos where characters can speak, sing, gesture, and emote—all with remarkable temporal consistency and visual realism.

The model can animate both real and fantastical characters, including 2D and 3D cartoons, mythical creatures, and even pets or inanimate objects with faces. It handles longform content, multiple speakers, and expressive nuance with a level of control that pushes far beyond typical AI video tools.

The company plans to roll AvatarFX into the Character.AI product suite in the coming months, with early access offered to CAI+ subscribers. You can join the waitlist here.

How AvatarFX Works

At the core of AvatarFX is a flow-based diffusion model built on top of the DiT (Diffusion Transformer) architecture, optimized for high-quality, realistic video generation. The system translates audio into synchronized movement—lip, head, and body gestures—with smooth continuity across long durations.

Key technical elements include:

• A high-efficiency training process that enables expressive, realistic motion across a range of characters.

• A novel inference strategy that preserves image quality and movement consistency over arbitrarily long video clips.

• Integration with Character.AI’s proprietary text-to-speech (TTS) voice model to power lifelike speech.

To support these capabilities, Character.AI engineered a robust data pipeline, carefully filtering low-quality videos while training on a wide range of motion types and visual aesthetics. For faster performance, the team employed state-of-the-art distillation techniques, reducing diffusion steps and cutting generation time without sacrificing quality.

How It’s Different

AvatarFX advances the field of AI-generated video in multiple standout ways:

• It can generate high-quality video from a single, user-provided image—offering more creative control than typical text-to-video systems.

• It delivers strong temporal consistency in facial expressions, hand gestures, and body movement.

• That consistency holds even in longform videos, across multiple dialogue turns.

• It supports a wide range of visual styles, including 2D animation, 3D cartoon characters, and non-human faces—like pets or fictional creatures.

These capabilities set AvatarFX apart in a growing market, positioning Character.AI at the forefront of storytelling-oriented multimodal AI. You can see examples of the generated videos here.

Redefining the Stack: From Lab to Launch

Character.AI is working to make this powerful model seamless for users. Their full-stack and infrastructure teams are focused on GPU orchestration, caching, media delivery, and intuitive design—so that generating a video will be as easy as clicking “Generate.”

The company is committed to making AvatarFX affordable, accessible, and user-friendly, while still delivering state-of-the-art results.

Prioritizing Safety

Even during testing, Character.AI has built in robust safeguards to ensure responsible use and prevent deepfakes. These include:

• Dialogue filtering to screen for policy-violating content.

• Blocking photo uploads of minors, political figures, and other high-profile individuals.

• AI anonymization of human likenesses to prevent deepfake misuse.

• Watermarking of all generated videos to signal they are synthetic.

• A strict one-strike policy tied to clear Terms of Service and Community Guidelines.

The safety measures reflect Character.AI’s proactive stance on preventing impersonation, harassment, and IP violations—ensuring that creativity doesn’t come at the cost of ethics.

What This Means

With AvatarFX, Character.AI is breaking ground on a new frontier of generative storytelling. This isn’t just animated lipsync—it’s full-spectrum performance from still images, powered by AI that understands motion, emotion, and voice. The implications span entertainment, education, content creation, and beyond.

As AI video tools evolve, the ability to animate characters with precision and control will likely reshape how we engage with media—making creativity faster, more personal, and increasingly interactive.

AvatarFX doesn’t just generate video—it breathes life into pixels, opening the door to the next generation of AI-powered expression.

Editor’s Note: This article was created by Alicia Shapiro, CMO of AiNews.com, with writing, image, and idea-generation support from ChatGPT, an AI assistant. However, the final perspective and editorial choices are solely Alicia Shapiro’s. Special thanks to ChatGPT for assistance with research and editorial support in crafting this article.