Method and apparatus for establishing an accurate low bit time stamp in a remotely created watermark

• US 8,416,983 B1
• Filed: 04/23/2010
• Issued: 04/09/2013
• Est. Priority Date: 04/23/2010
• Status: Active Grant

• Current Assignee: DIRECTV, LLC (AT&T, Inc.)
• Original Assignee: The DIRECTV Group, Inc. (AT&T, Inc.)
• Inventors: Joseph, Kuriacose
• Primary Examiner(s): Wang, Claire X.
• Assistant Examiner(s): JAMES, THOMAS AIDEN
• Application Number:
  US12/766,811
• Time in Patent Office: 1,082 Days
• Field of Search: None
• US Class Current: 382/100
• CPC Class Codes: H04N 21/42684 Client identification by a unique number or address, e.g. serial number, MAC address, socket ID network arrangements, protocols or services for addressing or naming H04L61/00
• CPC Class Codes: H04N 21/44204 Monitoring of content usage, e.g. the number of times a movie has been viewed, copied or the amount which has been watched monitoring of user activities for profile generation for accessing a video database G06F16/739; protecting generic digital content where the protection is independent of the precise nature of the content G06F21/10; arrangements for monitoring the use made of the broadcast services in broadcast systems H04H60/31
• CPC Class Codes: H04N 21/8358 involving watermark protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467

Abstract

A method and apparatus for placing a time stamp in a remotely applied watermark is disclosed. The method permits a time stamp of high resolution to be added remotely while minimizing the number of bits necessary in the time stamp.

Claims

1. A method for time stamping a retrieved version of a media program, comprising the steps of:

receiving a media program in a receiver remote from a headend, the media program having a first watermark including a time stamp describing a media program temporal datum to a first temporal resolution;

storing the media program;

retrieving the stored media program;

reading the first time stamp of the first watermark of the retrieved media program;

computing a second time stamp from the temporal difference between a time at which the media program is retrieved from storage and the media program temporal datum, the second time stamp having a second temporal resolution greater than the first temporal resolution;

generating a second watermark having the second time stamp;

embedding the second watermark in the retrieved media program; and

providing the media program and the embedded second watermark to a device external to the receiver.

2. The method of claim 1, wherein the second watermark further comprises a receiver unique identifier, and the method further comprises the steps of:

recovering the second watermark from the media program;

determining the second time stamp;

identifying the receiver from the receiver unique identifier, the second time stamp, and the media program temporal datum.

3. The method of claim 1, wherein the media program temporal datum describes the time the media program was first available for reception and download.

4. The method of claim 3, wherein the time the media program was first available for reception and download is described with respect to a global temporal datum.

5. The method of claim 4, wherein the first time stamp includes a count of n time periods after the global temporal datum.

6. The method of claim 4, wherein the second time stamp comprises at least k bits wherein:

7. The method of claim 4, wherein the second time stamp includes a count of m time periods after the first time stamp.

8. An apparatus for time stamping a retrieved version of a media program, comprising:

means for receiving a media program in a receiver remote from a headend, the media program having a first watermark including a time stamp describing a media program temporal datum to a first temporal resolution;

means for storing the media program;

means for retrieving the stored media program;

means for reading the first time stamp of the first watermark of the retrieved media program;

means for computing a second time stamp from the temporal difference between a time at which the media program is retrieved from storage and the media program temporal datum, the second time stamp having a second temporal resolution greater than the first temporal resolution;

means for generating a second watermark having the second time stamp;

means for embedding the second watermark in the retrieved media program; and

means for providing the media program and the embedded second watermark to a device external to the receiver.

9. The apparatus of claim 8, wherein the second watermark further comprises a receiver unique identifier, and the apparatus further comprises:

means for recovering the second watermark from the media program;

means for determining the second time stamp; and

means for identifying the receiver from the receiver unique identifier, the second time stamp, and the media program temporal datum.

10. The apparatus of claim 8, wherein the media program temporal datum describes the time the media program was first available for reception and download.

11. The apparatus of claim 10, wherein the time the media program was first available for reception and download is described with respect to a global temporal datum.

12. The apparatus of claim 11, wherein the first time stamp includes a count of n time periods after the global temporal datum.

13. The apparatus of claim 12, wherein the second time stamp comprises at least k bits wherein:

14. The apparatus of claim 12, wherein the second time stamp includes a count of m time periods after the first time stamp.

15. A system for time stamping a retrieved version of a media program, comprising:

a receiver, comprising;

a tuner for receiving a media program in a receiver remote from a headend disposed remotely from the receiver, the media program having a first watermark including a time stamp describing a media program temporal datum to a first temporal resolution;

a video storage device for storing the media program in the receiver and for retrieving the stored media program;

a watermark module, for reading the first time stamp of the first watermark of the retrieved media program, for computing a second time stamp from the temporal difference between a time that the stored media program is retrieved from storage and the media program temporal datum, the second time stamp having a second temporal resolution greater than the first temporal resolution, for generating a second watermark having the second time stamp, and for embedding the second watermark in the retrieved media program; and

means for providing the media program and the embedded second watermark to a device external to the receiver.

16. The system of claim 15, wherein the second watermark further comprises a receiver unique identifier, and the system further comprises:

a watermark analysis module for determining the receiver providing the media program, the watermark analysis module comprising;

a first module for recovering the second watermark from the media program;

a second module for determining the second time stamp; and

a third module for identifying the receiver from the receiver unique identifier, the second time stamp, and the media program temporal datum.

17. The system of claim 15, wherein the media program temporal datum describes the time the media program was first available for reception and download.

18. The system of claim 17, wherein the time the media program was first available for reception and download is described with respect to a global temporal datum.

19. The system of claim 18, wherein the first time stamp includes a count of n time periods after the global temporal datum.

20. The system of claim 19, wherein the second time stamp comprises at least k bits wherein:

21. The system of claim 19, wherein the second time stamp includes a count of m time periods after the first time stamp.