Method for watermarking a three-dimensional object

Patent metadata

Field	Value
Publication number	US-9922392-B2
Application number	US-201514924653-A
Country	US
Kind code	B2
Filing date	Oct 27, 2015
Priority date	Oct 27, 2014
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A method for watermarking a three-dimensional object is disclosed. The three-dimensional object is represented by a mesh. A mesh comprises a plurality of vertices. The method further comprises computing an original thickness signature for said mesh from a plurality of thickness values, wherein a thickness value is computed for a vertex of the mesh; determining a target thickness signature, wherein the target thickness signature is a function of a watermark payload and of the original thickness signature; and modifying a position of at least one vertex of the mesh wherein a thickness signature computed for the modified mesh reaches the target thickness signature and wherein a distortion constraint between the mesh and the modified mesh is satisfied.
A method for detecting a watermark in a three-dimensional object, a three-dimensional object carrying a watermark and, devices for implementing the methods are further disclosed.

First claim

The invention claimed is:

1. A method for watermarking a three-dimensional object, wherein said three-dimensional object is represented by a mesh, said mesh comprising a plurality of vertices, said method comprising:
Computing, using processor circuitry, an original thickness signature for said mesh from a plurality of thickness values, wherein a thickness value is computed for a vertex of said mesh and wherein said thickness value for a vertex comprises a distance between said vertex and a cloud of half diameter points wherein a half diameter point is a point placed along an internal normal of a vertex of said mesh at half the diameter value associated to said vertex;
Determining, using the processor circuitry, a target thickness signature as function of a watermark payload and of said original thickness signature;
Modifying, using the processor circuitry, a position of at least one vertex of the mesh wherein a thickness signature computed for said modified mesh reaches said target thickness signature and wherein a distortion constraint between said mesh and said modified mesh is satisfied;
wherein the watermarking is pose-invariant and resistant to noise addition and desynchronization attack.

2. The method according to claim 1 wherein modifying a position of at least one vertex of the mesh comprises using a solver in order to obtain said target thickness signature while minimizing a distortion metric between said mesh and said modified mesh.

3. The method according to claim 2 wherein said distortion metric comprises a mean square error of positions of said plurality of vertices.

4. The method according to claim 1 wherein said thickness signature comprises an average thickness value in each bin of an histogram of said plurality of thickness values or an area corresponding to a surface patch associated to the vertices within a bin of said histogram.

5. A method for detecting a watermark in a three-dimensional object, wherein said three-dimensional object is represented by a mesh comprising a plurality of vertices, said method comprising:
Computing, using processor circuitry, a thickness signature for said mesh from a plurality of thickness values, wherein a thickness value is computed for a vertex of said mesh and wherein said thickness value for a vertex comprises a distance between said vertex and a cloud of half diameter points wherein a half diameter point is a point placed along an internal normal of a vertex of said mesh at half the diameter value associated to said vertex;
Determining, using the processor circuitry, a watermark payload from said thickness signature,
wherein the watermark is pose-invariant and resistant to noise addition and desynchronization attack.

6. A method for creating a three-dimensional object, wherein said three-dimensional object is represented by a mesh, said mesh comprising a plurality of vertices, said three-dimensional object comprising:
a thickness signature computed, using processor circuitry, for said mesh from a plurality of thickness values is close to a target thickness signature, wherein a thickness value is computed for a vertex of said mesh and wherein said thickness value for a vertex comprises a distance between said vertex and a cloud of half diameter points wherein a half diameter point is a point placed along an internal normal of a vertex of said mesh at half the diameter value associated to said vertex;
said target thickness signature being a function of a watermark payload and an original thickness signature corresponding to an original three-dimensional object wherein the watermark payload is pose-invariant and resistant to noise addition and desynchronization attack.

7. A device for watermarking a three-dimensional object wherein said three-dimensional object is represented by a mesh, said mesh comprising a plurality of vertices, the device comprising at least one processor configured to:
Compute, using processor circuitry, an original thickness signature for said mesh from a plurality of thickness values, wherein a thickness value is computed for a vertex of said mesh, and wherein said thickness value for a vertex comprises a distance between said vertex and a cloud of half diameter points wherein a half diameter point is a point placed along an internal normal of a vertex of said mesh at half the diameter value associated to said vertex;
Determine, using the processor circuitry, a target thickness signature as function of a watermark payload and of said original thickness signature;
Modify, using the processor circuitry, a position of at least one vertex of the mesh wherein a thickness signature computed for said modified mesh reaches said target thickness signature and wherein a distortion constraint between said mesh and said modified mesh is satisfied;
wherein the watermarking is pose-invariant and resistant to noise addition and desynchronization attack.

8. The device according to claim 7 wherein to modify a position of at least one vertex of the mesh, said device further comprises a solver in order to obtain said target thickness signature while minimizing a distortion metric between said mesh and said modified mesh.

9. The device according to claim 8 wherein said distortion metric comprises a mean square error of positions of said plurality of vertices.

10. A device for detecting a watermark in a three-dimensional object wherein said three-dimensional object is represented by a mesh comprising a plurality of vertices, said device comprising at least one processor configured to:
Compute, using processor circuitry, a thickness signature for said mesh from a plurality of thickness values, wherein a thickness value is computed for a vertex of said mesh and wherein said thickness value for a vertex comprises a distance between said vertex and a cloud of half diameter points wherein a half diameter point is a point placed along an internal normal of a vertex of said mesh at half the diameter value associated to said vertex;
Determine, using the processor circuitry, a watermark payload from said thickness signature;
wherein the watermark is pose-invariant and resistant to noise addition and desynchronization attack.

11. A non-transitory program storage device, readable by a computer, tangibly embodying a program of instructions executable by the computer to perform a method for watermarking a three-dimensional object represented by a mesh, said mesh comprising a plurality of vertices, said method comprising:
Computing, using processor circuitry, an original thickness signature for said mesh from a plurality of thickness values, wherein a thickness value is computed for a vertex of said mesh and wherein said thickness value for a vertex comprises a distance between said vertex and a cloud of half diameter points wherein a half diameter point is a point placed along an internal normal of a vertex of said mesh at half the diameter value associated to said vertex;
Determining, using the processor circuitry, a target thickness signature as function of a watermark payload and of said original thickness signature;
Modifying, using the processor circuitry, a position of at least one vertex of the mesh wherein a thickness signature computed for said modified mesh reaches said target thickness signature and wherein a distortion constraint between said mesh and said modified mesh is satisfied;
wherein the watermarking is pose-invariant and resistant to noise addition and desynchronization attack.

Assignees

• Thomson Licensing

Inventors

• Rolland-Neviere Xavier
• Doerr Gwenael
• Alliez Pierre

Classifications

• G06T2201/0083

  whereby only watermarked image required at decoder, e.g. source-based, blind, oblivious · CPC title

• G06T1/0092 Primary

  Payload characteristic determination in a watermarking scheme, e.g. number of bits to be embedded · CPC title

• G06T2201/0065

  Extraction of an embedded watermark; Reliable detection · CPC title

• G06T17/205

  Re-meshing · CPC title

• G06T2201/0051

  Embedding of the watermark in the spatial domain · CPC title