Facial Animation Transfer via Neural Network Pose Alignment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current facial animation technologies face challenges in accurately transferring motion patterns from a driving video to a target image across a wide range of head poses and facial expressions, especially when the poses and expressions do not match.

Innovation Solution

The facial animation system employs an image transformation neural network to generate a modified source image sequence by identifying matching head poses and facial expressions from driving image sequence data and expression datasets, using a combination of keypoint detector, dense motion, and image generation neural networks to align and transform the source images.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If facial animation technologies use simple motion transfer methods, then the process is fast and simple, but the accuracy of motion pattern transfer across different head poses and facial expressions deteriorates

Engineering Contradiction:
Improveaccuracy of motion pattern transferVSAvoidcomplexity of animation system
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The system segments the facial animation process into multiple specialized neural network components: a keypoint detector network for identifying facial landmarks, a dense motion network for computing motion patterns, and an image generation network for synthesizing final frames. This segmentation allows each component to specialize in a specific aspect of motion transfer, improving overall accuracy while maintaining manageable system complexity through modular architecture.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces intermediate representations including dense motion patterns and keypoint trajectories as mediators between the driving video and target image. These intermediaries enable accurate transfer of complex facial expressions and head poses by breaking down the transformation into learnable stages, allowing the system to handle diverse poses and expressions with high fidelity.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If the system uses multiple neural networks for precise pose and expression matching, then the animation accuracy improves, but the computational time and processing complexity increase

Engineering Contradiction:
Improveprecision of head pose and facial expression matchingVSAvoidcomputational processing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The keypoint detector network performs preliminary action by identifying facial keypoints and establishing correspondence between driving and target faces before the main motion transfer process. This preliminary keypoint detection enables the subsequent dense motion network to focus computational resources on calculating motion patterns rather than searching for correspondences, significantly reducing overall processing time while maintaining high precision in pose and expression matching.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system employs dynamic adaptive processing where the complexity of computation adjusts based on the input. The neural networks dynamically allocate computational resources to regions of the face with greater motion or expression changes, allowing precise matching of head poses and facial expressions while minimizing unnecessary computations in stable regions, thus reducing overall processing time.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentUS12125129B2Facial animation transfer
Publication Date: 2024.10.22 SNAP INC
  • US12125129B2 patent drawing
  • US12125129B2 patent drawing
  • US12125129B2 patent drawing

AI summary

Systems and methods are disclosed for generating, a source image sequence using an image sensor of the computing device, the source image sequence comprising a plurality of source images depicting a head and face, identifying driving image sequence data to modify face image feature data in the source image sequence, generating, using an image transformation neural network, a modified source image sequence comprising a plurality of modified source images depicting modified versions of the head and face, and storing the modified source image sequence on the computing device.