Animation Compression: Table of Contents

21 Oct 2016

Character animation compression is an exotic topic that seems to need to be re-approached only about once per decade. Over the course of 2016 I’ve been developing a novel twist to an older technique and I was lucky enough to be invited to talk about it at the 2017 Game Developers Conference (GDC). This gave me the sufficient motivation to write this series.

The amount of material available regarding animation compression is surprisingly thin and often poorly detailed. My hope for this series is to serve as a reference for anyone looking to improve upon or implement efficient character animation compression techniques.

Each post is self-contained and detailed enough to be approachable to a wide audience.

Table of Contents

• Preface
• Terminology
• Animation Data
  • Animation Data in Numbers
• Measuring Compression Accuracy
  • Simulating mesh skinning
  • Dominance based error estimation
• Constant Tracks
• Range Reduction
• Uniform Segmenting
• Main Compression Families
  • Simple Quantization
  • Advanced Quantization
  • Sub-sampling
  • Linear Sample Reduction
    • Pitfalls of linear sample reduction: Part 1
    • Pitfalls of linear sample reduction: Part 2
    • Pitfalls of linear sample reduction: Part 3
    • Pitfalls of linear sample reduction: Part 4
  • Curve Fitting
  • Signal Processing
• Error Compensation
• Bind Pose Optimizations
  • Bind Pose Additive
  • Bind Pose Stripping
• Clip metadata packing
• Morph Target Animation Compression
• Progressive Animation Streaming
• Compressing looping animations
• Manipulating the sampling time for fun and profit
• Case Studies
  • Unreal 4
  • Unity 5
• GDC 2017 Presentation

ACL: An open source solution

My answer to the lack of open source implementations of the above algorithms and topics has prompted me to start my own. See all the code and much more over on GitHub for the Animation Compression Library as well as its Unreal Engine plugin!