Security and/or tracing video media-content

1. A method of securing and/or tracing video media-content which comprises a plurality of frames, the method comprising:

arranging a media-delivery platform to have a plurality of target devices connected thereto and further arranging the media-delivery platform to deliver the video media-content to a user ID being used at one of the target devices;

recording a reference fingerprint representing the video media-content;

receiving the video-media content at the target device;

generating, at each target device, a unique identifier based on the user ID being used at the device to which media content is being delivered, wherein;

i) the unique identifier is provided as one or more opaque, or at least semi-transparent visual markers to be overlaid at positions relative to at least one frame of the video media content, where the positions are calculated based on the user ID; and

ii) the visual markers are to be overlaid on at least one frame of the video media content such that the visual markers occur at a predetermined time relative to the video media-content;

overlaying the opaque, or at least semi-transparent, visual markers on the video-media content and causing the combined video-media content and visual markers to be displayed;

monitoring a network to detect video media-content having a fingerprint which is the same, or at least substantially the same, as the reference fingerprint where each so detected video media-content provides a candidate media-content from which the unique identifier is to be extracted; and

extracting the unique identifier from within the or each candidate video media-content to identify the user ID being used at the target device to which the video media-content was delivered.

2. The method of claim 1 wherein the candidate media-content is temporally aligned, with the reference media content to allow the frames on which the visual markers have been placed to be identified, wherein the alignment is performed using the reference fingerprint and the fingerprint obtained from the candidate media-content.

3. The method of claim 1 in which the unique identifier is calculated based upon a variable in addition to the user ID, wherein the variable varies in a known manner.

4. The method of claim 3 in which the variable is time.

5. A method of securing video media-content which comprises a plurality of frames, the method comprising:

receiving, at a target device, video media-content from a media-delivery platform; and

generating, at the target device, a unique identifier based on a user ID being used at that target device, wherein

the unique identifier is provided as one or more opaque, or at least semi-transparent visual markers to be overlaid at positions relative to at least one frame of the video media content, where the positions are calculated based on the user ID;

the visual markers are overlaid on at least one frame of the video media content such that the visual markers occur at a predetermined time relative to the video media-content; and

overlaying the opaque, or at least semi-transparent, visual markers on the video-media content and causing the combined video-media content and visual markers to be displayed.

6. The method of claim 5 wherein the target device is a set-top box arranged to display video media content.

7. The method of claim 6 wherein the set-top box is arranged to receive and cause to be displayed broadcast media content.

8. The method of claim 6 wherein the set-top box is arranged to superimpose the unique identifier onto the video media content.

9. The method of claim 6 wherein the set top box is arranged to output a marked stream, for display, comprising both the media content and superimposed unique identifier.

10. The method of any of claim 6 in which the set top box is caused to download an application arranged to add the unique identifier.

11. The method of claim 10 in which the application is arranged to add the unique identifier at predetermined times.

12. A method of securing and/or tracing video media-content which comprises a plurality of frames, according to claim 5 , the method comprising:

receiving at least one candidate media-content which has been determined to have a fingerprint substantially the same as a reference fingerprint generated for the video media-content;

processing, the candidate media-content to temporally align the reference fingerprint with the reference video media-content used to generate the reference to allow the frames on which a visual maker has been placed to be identified, wherein the alignment is performed using the reference fingerprint and the fingerprint obtained from the candidate media-content; and

extracting the unique identifier from the identified frames within the or each candidate video media-content to identify the user ID held within the unique identifier.

13. A non-transitory machine readable storage medium containing instructions which when read by a machine, cause a processor of that machine to perform the following steps:

receive, at a target device, video media-content from a media-delivery platform;

generate, at the target device, a unique identifier based on a user ID being used at that target device, wherein

the unique identifier is provided as one or more opaque, or at least semi-transparent visual markers to be overlaid at positions relative to at least one frame of the video media content, where the positions are calculated based on the user ID;

the visual markers are overlaid on at least one frame of the video media content such that the visual markers occur at a predetermined time relative to the video media-content; and

overlay the opaque, or at least semi-transparent, visual markers on the video-media content and causing the combined video-media content and visual markers to be displayed.

14. A non-transitory machine readable storage medium containing instructions which when read by a machine, cause a processor of that machine to perform as a server to provide the following steps:

deliver video media-content to a user ID being used at a target device connected to the server;

record a reference fingerprint representing the video media-content;

wherein the target devices are arranged to:

a) generate, a unique identifier based on the user ID being used at the device to which media content is being delivered, wherein;

i) the unique identifier is provided as one or more opaque, or at least semi-transparent visual markers to be overlaid at positions relative to at least one frame of the video media content, where the positions are calculated based on the user ID; and

ii) the visual markers are to be overlaid on at least one frame of the video media content such that the visual markers occur at a predetermined time relative to the video media-content; and

b) overlay the opaque, or at least semi-transparent, visual markers on the video-media content and causing the combined video-media content and visual markers to be displayed;

monitor a network to detect video media-content having a fingerprint which is the same, or at least substantially the same, as the reference fingerprint where each so detected video media-content provides a candidate media-content from which the unique identifier is to be extracted; and

extract the unique identifier from within the or each candidate video media-content to identify the user ID being used at the target device to which the video media-content was delivered.

15. A system arranged to secure and/or trace video media-content which comprises a plurality of frames, the system comprising:

a media-delivery platform arranged to:

i) have a plurality of target devices connected thereto;

ii) deliver the video media-content to a user ID being used at one of the target devices; and

iii) record a reference fingerprint representing the video media-content that is delivered to the or each target device;

wherein the or each target device is arranged to generate a unique identifier based on a user ID being used at the device to which media content is being delivered, wherein;

i) the unique identifier is provided as one or more opaque, or at least semi-transparent visual markers to be overlaid at positions relative to at least one frame of the video media content, where the positions are calculated based on the user ID; and

ii) the visual markers are to be overlaid on at least one frame of the video media content such that the visual markers occur at a predetermined time relative to the video media-content;

and wherein the system is arranged to monitor a network to detect video media-content having a fingerprint which is the same, or at least substantially the same, as the reference fingerprint where each so detected video media-content provides a candidate media-content to be decoded;

the system being arranged to process the candidate media-content after comparison with the video media-content used to generate the reference fingerprint to temporally align the candidate media-content to identify which frames contain the unique identifier; and

wherein the system is further arranged to extract the unique identifier from the identified frames within the or each candidate video media-content to identify the user ID being used at the target device to which the video media-content was delivered.

16. The system of claim 15 wherein the system further comprises a target device arranged to:

receive video media-content from a media-delivery platform;

generate a unique identifier based on a user ID being used at that target device, wherein the unique identifier comprises one or more visual markers distributed across at least one frame of the video media-content at positions which are calculable based on the user ID; and

cause the at least one frame of video content having the unique identifier to be displayed at calculable times when the video media-content is displayed.

17. The system of claim 16 wherein the target device comprises a set-top box.

18. The system of claim 17 wherein the set-top box is arranged to receive and cause to be displayed broadcast media content.

19. The system of claim 17 wherein the set-top box is arranged to superimpose the unique identifier onto the video media content.

20. The system of claim 19 wherein the set-top box is arranged to output a marked stream, for display, comprising both the media content and superimposed unique identifier.