Method and apparatus for hardware-enforced, always-on insertion of a watermark in a video processing path
A method, apparatus, article of manufacture, and a memory structure for inserting a watermark in a media program is described. In an exemplary embodiment, the method comprises the steps of receiving data comprising the media program in the receiver disposed at a subscriber station, generating a watermark, the watermark generated at least in part according to a secure data processor-unique identifier irreversibly stored in the secure data processor, processing the received data to reproduce the media program, and inserting portions of the generated watermark in the reproduced media program at locations determined at least in part according to the secure data processor-unique identifier to produce a watermarked media program provided for display.
1. A method of adding watermark data to a media program in a receiver, comprising:
(a) receiving data comprising the media program in the receiver disposed at a subscriber station;
(b) generating, at least in part with a secure data processor executing instructions permanently and unchangeably coded into a secure memory of the secure data processor, a watermark, wherein the watermark is generated at least in part according to an identifier uniquely associated with and securely stored in the secure data processor, comprising:
(b) (1) combining the secure data processor-unique identifier and a secret value to create a receiver-unique value by encrypting the secure data processor-unique identifier according to the secret value to create a receiver-unique value;
(b) (2) generating a header comprising a start of frame marker; and
(b) (3) concatenating the header and the receiver-unique value to produce the generated watermark;
(c) processing the received data to reproduce the media program; and
(d) inserting portions of the generated watermark in a reproduced media program at locations determined at least in part according to the secure data processor-unique identifier to produce a watermarked media program provided for display, comprising:
(d)(1) inserting a first portion of the portions of the generated watermark in a first portion of a first frame of the reproduced media program;
(d)(2) inserting a further portion of the portions of the generated watermark in a further portion of a subsequent frame of the media program, wherein a location of the further portion of the generated watermark within the subsequent frame of the reproduced media program is selected at least in part according to the secure data processor-unique value;
(d)(3) repeating step (d)(2) until all of the generated watermark is inserted in the media program; and
(d)(4) repeating steps (d)(1)-(d)(3) to insert the generated watermark in further frames of the media program.
2. The method of claim 1 , wherein steps (b)-(d) are performed by the secure data processor.
3. The method of claim 1 , wherein:
the media program comprises a plurality of frames; and
each of the portions of the watermark are inserted into an associated one of the plurality of frames according to a deterministic interval.
4. The method of claim 3 , further comprising the steps of:
searching for and reading the inserted first portion of the portions of the generated watermark in the first frame of the reproduced media program;
searching for and reading the inserted further portion of the portions of the generated watermark in the subsequent frame of the reproduced media program; and
combining the read first portion and the read further portion to recover at least a portion of the inserted watermark.
5. The method of claim 1 , wherein the location of the further portion of the generated watermark within the subsequent frame of the reproduced media program is selected at least in part according to the secure data processor-unique value and a secret value.
6. The method of claim 1 , further comprising:
(e) searching for and reading a start of frame maker in the media program to find the first portion of the generated watermark;
(f) searching for and reading the subsequent frame of the media program for the further portion of the generated watermark;
(g) concatenating the first portion of the generated watermark and the further portion of the generated watermark;
(h) repeating steps (e)-(g) until the generated watermark is regenerated; and
(i) reproducing the secure processor unique identifier from the regenerated watermark.
7. An apparatus for adding watermark data to a media program comprising:
a tuner for receiving data comprising the media program in the receiver disposed at a subscriber station; and
a secure data processor, communicatively coupled to the tuner, the secure data processor executing instructions permanently and unchangeably coded into a secure memory of the secure data processor, the instructions comprising instructions for:
generating a watermark, the watermark generated at least in part according to an identifier uniquely associated with and securely stored in the secure data processor, comprising;
combining the secure data processor-unique identifier and a secret value to create a receiver-unique value by encrypting the secure data processor-unique identifier according to the secret value to create a receiver-unique value;
generating a header comprising a start of frame marker; and
concatenating the header and the receiver-unique value to produce the generated watermark;
processing the received data to reproduce the media program; and
inserting portions of the generated watermark in a reproduced media program at locations determined at least in part according to the secure data processor-unique identifier to produce a watermarked media program provided for display;
wherein the instructions for inserting portions of the generated watermark in the reproduced media program at locations determined at least in part according to the secure data processor-unique identifier comprise instructions for:
(1) inserting a first portion of the portions of the generated watermark in a first portion of a first frame of the reproduced media program;
(2) inserting a further portion of the portions of the generated watermark in a further portion of a subsequent frame of the media program, wherein a location of the further portion of the generated watermark within the subsequent frame of the reproduced media program is selected at least in part according to the secure data processor-unique value;
(3) repeating (2) until all of the generated watermark is inserted in the media program; and
(4) repeating steps (1)-(3) to insert the generated watermark in further frames of the media program.
8. The apparatus of claim 7 , wherein
the media program comprises a plurality of frames; and
the secure data processor inserts each of the portions of the watermark into an associated one of the plurality of frames according to a deterministic interval.
9. The apparatus of claim 7 , wherein the secure data processor-unique identifier is irreversibly stored in the secure data processor.
10. The apparatus of claim 7 , wherein the secure data processor is a transport chip comprising a system on a chip (SOC).
11. The apparatus of claim 7 , wherein:
the reproduced media program comprises a plurality of reproduced media program frames;
the secure data processor comprises a video frame buffer for storing frames of the reproduced media program frame; and
the portions of the generated watermark are inserted into the reproduced media program frames while stored in the video frame buffer.
12. The apparatus of claim 11 , wherein the secure data processor further generates the watermark at least in part according to a secret value securely accessible to the secure data processor.
13. The apparatus of claim 7 , wherein the location of the further portion of the generated watermark within the subsequent frame of the reproduced media program is selected at least in part according to the secure data processor-unique value and the secret value.
14. The apparatus of claim 7 , wherein the watermark comprises data for forensically identifying the receiver that reproduced the media program.