3D Talking Head with Lip Sync in Three.js

Your approach using morph targets (blend shapes) for lip sync animation is indeed a reasonable and common method for this type of project. Here's an assessment of your plan and some considerations:

Your Approach

Using morph targets via morphTargetInfluences is a solid technique for lip sync animation because:

1. It allows for smooth transitions between different mouth shapes
2. It's well-supported in the glTF format
3. It's relatively performant compared to some alternatives
4. Three.js has built-in support for morph targets

Implementation Steps

1. Find a suitable head model on Sketchfab
2. In Blender:
   • Create various mouth shapes (visemes) as morph targets
   • Typically you'll need shapes for phonemes like "A", "E", "I", "O", "U", "F", "M", etc.
   • Ensure the model is properly rigged if you want additional facial expressions
3. Export as glTF with morph targets included
4. Load in Three.js using GLTFLoader:

JAVASCRIPTCopied
const loader = new THREE.GLTFLoader();
loader.load('path/to/model.glb', (gltf) => {
  const model = gltf.scene;
  scene.add(model);
  
  // Find the head/face mesh with morph targets
  const headMesh = model.getObjectByName('HeadMesh');
  
  // Now you can animate the morph targets
  // headMesh.morphTargetInfluences[0] = 0.5; // Example
});

5. For the lip sync, you'll need to analyze the audio input to determine which mouth shapes to use at what times.

Alternative Approaches

1. Bone-based animation: Using a facial rig with bones (via SkinnedMesh and Skeleton) - more complex but can be more flexible for certain animations.

2. Combination approach: Using both morph targets for lip sync and a skeletal system for broader facial expressions.

Loading and Animation Tools

Based on the context provided, you'll want to use:

• GLTFLoader for loading your model
• Possibly SkinnedMesh if you include bone animations
• The model would likely be a Mesh or SkinnedMesh object

Considerations

• Ensure your morph targets are well-defined and cover all necessary mouth shapes
• Consider adding additional morph targets for expressions (smiling, frowning, etc.)
• Audio analysis for lip sync can be challenging - you might want to look into existing libraries for this
• For real-time user input, you'll need to process audio with minimal latency

This approach should give you smooth lip animations if implemented correctly. The key is creating quality morph targets in Blender and properly mapping audio phonemes to the appropriate mouth shapes.