Watermark embedding functions in rendering description files

• US 20010054150A1
• Filed: 03/16/2001
• Published: 12/20/2001
• Est. Priority Date: 03/18/2000
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Levy, Kenneth L.
• Granted Patent: US 7,142,691 B2
• Time in Patent Office: Days
• US Class Current: 713/176
• CPC Class Codes: G06F 21/1063 Personalisation

Abstract

A method for controlling watermark embedding in a media object through the use of a watermark embedding command. In the process of creating the media object, the method includes a watermark embedding command among a set of one or more rendering commands that specify how the media object is to be rendered. For example, certain media signal formats like PCL, PDF, or postscript for images, MIDI and structured audio for audio signals, and MPEG-4 and MPEG-7 for audio and video signals, include descriptors that control how a particular media signal is to be rendered. The watermark embedding command includes a combination of the following items: an identifier used to link to customer or related content information, the customer'"'"'s web site, the intensity at which to embed the watermark, areas not to embed, batch processing options, printing preferences for images, watermarking embedding methods to use on different media types, formats, or different parts of the media object, and desired rendering quality.

Claims

1. A method for controlling embedding of a digital watermark in a media object, comprising:

receiving a watermark embedding function specifying watermark embedding parameters, including watermark intensity and message payload;

inserting the watermark embedding function into a rendering description file; and

at rendering time, reading the watermark embedding function and steganographically embedding the watermark message payload into the media object at the watermark intensity.

2. The method of

claim 1

wherein the media object comprises graphic art including a collection of two or more images in different formats.

3. The method of

claim 1

wherein the media object comprises a music signal, and the steganographic embedding process is adapted to the robustness or perceptual quality parameters selected at the rendering time.

4. The method of

claim 1

wherein the media object comprises a music signal, and the steganographic embedding process is adapted to the robustness or perceptual quality parameters selected at the rendering time.

5. The method of

claim 1

wherein the steganographic embedding process includes:

iteratively embedding the message payload in two or more iterations;

analyzing the error detection rate of the message payload in each iteration; and

adjusting a robustness parameter of the embedding process for at least one of the iterations so that the error detection rate is at an acceptable level.

6. The method of

claim 1

including:

providing two or more different watermark embedding modules, each adapted for different rendering processes or transmission channels, the watermark embedding modules being selected at rendering time depending on the rendering process or transmission channel to which the media object is to be applied.

7. The method of

claim 1

wherein the watermark embedding function specifies the embedding locations of the watermark.

8. The method of

claim 1

wherein, at rendering time, the steganographic embedding process selects the embedding locations of the watermark depending on the rendering process.

9. The method of

claim 1

wherein the media object comprises an image, and the steganographic embedding process embeds the watermark message payload into the image after the image is rasterized into a format compatible with a printer on which the image is to be printed.

10. The method of

claim 1

wherein the watermark message payload is embedded in the image after it is converted into a halftone image by a halftoning process compatible with the printer on which the image is to be printed.

11. A media object processing system comprising:

input means for enabling a user to specify rendering commands for a media object, including a watermark embedding function to be applied to the media object, the watermark embedding function including a watermark message payload, and parameters controlling embedding of the watermark message payload in the media object;

means for creating a rendering description file describing how to render the media object; and

a watermark embedder module for steganographically embedding the watermark message payload into the media object.

12. The system of

claim 11

where in the system is operable to select different embedding modules for different rendering processes.

13. The system of

claim 11

wherein the embedder module is operable to iteratively embed the watermark message payload in the media object in two or more iterations, and with each iteration, analyzing an error detection rate of the message payload to adapt robustness of the watermark.

14. The system of

claim 13

wherein the watermark embedder module applies a degradation process to a watermarked media signal output from an iteration before analyzing the error detection rate.

15. The system of

claim 11

wherein the media object comprises graphic art that is at least in part specified by a rendering command that has not be converted into a rasterized image when the watermark embedding function is inserted in the rendering description file.

16. The system of

claim 11

wherein the media object comprises structured audio represented, at least in part, by a rendering command that has not been converted to an audio signal when the watermark embedding function is inserted in the rendering description file.

17. The system of

claim 11

wherein the media object comprises rendering commands specifying how to create a video sequence that have not been converted to a video signal when the watermark embedding function is inserted in the rendering description file.

18. A computer readable medium having a rendering description file comprising:

one or more rendering commands describing how to render a media object; and

a watermark embedding function specifying how to embed a watermark message payload into the media object after the media object has been rendered.

19. The computer readable medium of

claim 18

wherein the rendering description file includes a rendering command describing how to create a rasterized image, the watermark embedding function specifying how to embed the watermark message in the rasterized image.

20. The computer readable medium of

claim 19

wherein the watermark embedding function including a watermark intensity parameter and embedding locations specifying where and at what intensity to embed the watermark message in the rasterized image.