1.  ALICE creates a 3D model. She wants to sell it, but she wants to be protected against theft, so
  2. She watermarks the model. The watermarked version is perceptually identical to the original (the watermark is invisible), although there are some tiny changes.
  3. This is what the the model would look like if those changes were exaggerated.

  4. BOB steals Alice's model.
  5. For his purposes, he changes the model (for instance, he adds noise to vertex coordinates, rotates, scales & translates the model, and also simplifies it to half the number of faces)
  6. Alice notices that Bob is using a model suspiciously similar to hers, so she takes Bob's model and checks if it contains her watermark:
  7. first, she aligns (registers) the suspect model with her original,
  8. then, she resamples it to see how much has each vertex moved from the original to the suspect mesh,
  9. and finally, she compares these motion vectors with the changes induced by the watermark. Since the watermark predicted with high accuracy the diference between Bob's model and her original, she can prove that Bob stole her model.
  10. Bob pays Alice a lot of money.