Method and system for augmented reality

1. A method of augmented reality, comprising the steps of:

associating, by one or more processors, tint information with a predetermined graphical object, the tint information identifying colour space values specifying a change in colour balance;

receiving a video image of a real scene comprising a feature for detection;

detecting, by the one or more processors, the feature in the video image of the real scene and selecting a graphical object responsive to the detected feature; and

augmenting, by the one or more processors, the video image with the selected graphical object;

and in which

when the selected graphical object is the predetermined graphical object:

retrieving the tint information associated with the predetermined graphical object; and

modifying, by the one or more processors, a colour balance of the video image responsive to the tint information by applying the tint information as a value shift in colour channels of the colour space to an extent specified by the tint information, the value shift being either a proportional or an absolute value shift in the colour channels.

2. The method of claim 1 in which the colour balance is modified uniformly over the whole video image.

3. The method of claim 1 in which the colour balance is modified to an extent dependent on a position of a video image pixel with respect to a position of the predetermined graphical object that it will occupy in the augmented video image.

4. The method of claim 3 in which the colour balance is modified to an extent proportional to the distance of a video image pixel from a position of the predetermined graphical object that it will occupy in the augmented video image.

5. The method according to claim 3 , in which position offset information is associated with the tint information, and the position of the predetermined graphical object is derived with reference to the position offset information.

6. The method according to claim 1 , in which the colour balance is modified in a time variant manner.

7. The method according to claim 1 , comprising the steps of:

associating brightness information with the predetermined graphical object; and

when the selected graphical object is the predetermined graphical object, modifying the brightness of the video image responsive to the brightness information.

8. The method according to claim 1 , in which the feature for detection is a fiduciary marker.

9. The method of claim 8 , in which the fiduciary marker is one of a plurality of respective fiduciary markers printed in a book.

10. A non-transitory computer-readable storage medium storing computer program instructions thereon, the computer instructions, when executed by a processor, implement a method comprising the steps of:

receiving a video image of a real scene comprising a feature for detection;

detecting the feature in the video image of the real scene and selecting a graphical object responsive to the detected feature; and

augmenting the video image with the selected graphical object;

and in which

when the selected graphical object is the predetermined graphical object:

retrieving tint information associated with the predetermined graphical object, the tint information identifying colour space values specifying a change in colour balance; and

modifying a colour balance of the video image responsive to the tint information by applying the tint information as a value shift in colour channels of the colour space to an extent specified by the tint information, the value shift being either a proportional or an absolute value shift in the colour channels.

11. An entertainment device for generating an augmented reality image for display, comprising:

a processor means for associating tint information with a predetermined graphical object, the tint information identifying colour space values specifying a change in colour balance;

an input means for receiving a video image of a real scene comprising a feature for detection;

the processor means being configured to detect the feature in the video image of the real scene, and to select a graphical object responsive to the detected feature;

and graphics processing means for augmenting the video image with the selected graphical object;

and in which

when the selected graphical object is the predetermined graphical object,

the processor means is configured to retrieve the tint information associated with the predetermined graphical object; and

the graphics processing means is operable to modify a colour balance of the video image responsive to the tint information by applying the tint information as a value shift in colour channels of the colour space to an extent specified by the tint information, the value shift being either a proportional or an absolute value shift in the colour channels.

12. The entertainment device of claim 11 , in which the graphics processing means is configured to modify the colour balance to an extent dependent on the position of a video image pixel with respect to the position that the predetermined graphical object will occupy in the augmented video image.

13. The entertainment device of claim 11 , in which:

the processor means is configured to associate brightness information with the predetermined graphical object; and

when the selected graphical object is the predetermined graphical object,

the graphics processing means is configured to modify the brightness of the video image responsive to the brightness information.

14. A system for generating an augmented reality image for display, comprising

the entertainment device of claim 11 ; and

a video camera operably coupled to the entertainment device.

15. The system of claim 14 , comprising:

a book comprising one or more turnable leaves, upon whose pages are printed respective fiduciary markers.