System and method for optically communicating information between a display and a camera

• US 7,411,609 B2
• Filed: 06/25/2004
• Issued: 08/12/2008
• Est. Priority Date: 09/08/2000
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Shafer, Steven A. N., Brumitt, Barrett L., Harris, Stephen C.
• Primary Examiner(s): Hannett; James M
• Application Number:
  US10/877,852
• Publication Number:
  US 20040233293A1
• Time in Patent Office: 1,509 Days
• Field of Search: 348/207.11, 348/211.99, 348/211.1, 348/211.2, 348/211.8, 348/207.1
• US Class Current: 348/211.1
• CPC Class Codes: H04N 23/66 Remote control of cameras or camera parts, e.g. by remote control devices
• CPC Class Codes: H04N 23/90 Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums
• CPC Class Codes: H04N 5/2224 related to virtual studio applications

Abstract

A system and a method for optically communicating information between a display and a camera that is observing the display. In general, the transmission of information is unidirectional in a direction from the display to the camera. The display transmits information to the camera that is observing the display by displaying a series of symbols and images (such as an alphabet) on the display. Information (such as a network address of the display or camera) may be transmitted to the camera without any prior shared knowledge between the two. The present invention also is capable of determining a spatial location (or pose) of the display (relative to a camera observing the display) by observing a pattern presented on the display and using well-known correlation techniques.

Claims

1. A method for optically communicating information between an image source and an image detector, comprising:

obtaining a maximum value of each color component for each pixel over an image sequence captured by the image detector to produce a stabilized aggregate image from the captured image sequence;

communicating each of a plurality of communication symbols in sequence from the image source to the image detector; and

optically transmitting the information from the image source to the image detector using at least some of the communication symbols.

2. The method of claim 1, wherein the information is at least one of:

(a) network location of the image source;

(b) spatial location of the image source.

3. The method of claim 1, further comprising locating the image source using an attention signal.

4. The method of claim 1, further comprising defining and storing each of the transmitted communication symbols at the image detector in the same sequence as the communication symbols were transmitted.

5. The method of claim 1, further comprising:

assigning a definition to each of the plurality of communication symbols received in sequence by the image detector; and

decoding the transmitted information using the definitions of the plurality of communication symbols.

6. The method of claim 5, wherein the communication symbols are unknown to the image detector before the assigning of definitions.

7. The method of claim 1, wherein the communication symbols further comprise an alphabet containing 16 different symbols.

8. The method of claim 7, wherein at least some of the communication symbols have special codes associated with them.

9. The method of claim 7, wherein each of the plurality of communication symbols is communicated in numerical order.

18. The method of claim 1, further comprising optically communicating each of the plurality of communication symbols one at a time in sequence from the image source to the image display detector.

10. A method for optically communicating information between an image source and an image detector observing the image source and not otherwise in communication with each other, comprising:

displaying an attention signal being a transition of the image source from blue to red to notify the image detector that the image source is ready to establish an optical communication link; and

displaying communication symbols previously defined to the image detector so as to represent the information being communicated to the image detector.

11. The method of claim 10, wherein the communicated information is used to establish a network communication link between the image source and the image detector.

12. The method of claim 10, further comprising displaying the attention signal on the image source whenever the image source is ready to transmit information to the image detector, wherein the attention signal is recognized by the image detector as an indication that the image source will begin transmitting information.

13. The method of claim 10, further comprising defining the communication symbols to the image detector by displaying one at a time on the image source each of the communication symbols in sequence.

14. A method for automatically establishing network communication between a display and a camera that are not initially in network communication, comprising:

informing the camera through the display that the display will be optically transmitting data by displaying an attention signal of transitioning the display from an entirely blue screen to an entirely red screen;

optically transmitting each of the communication symbols one at a time in a numerical sequence from the display to the camera;

receiving each of the communication symbols and storing a definition associated with each symbol in an interpretation file;

optically transmitting a network address using the communication symbols through the display to the camera; and

using the network address to establish network communication between the display and the camera.

15. The method of claim 14, wherein the communication symbols include an alphabet representing whole numbers from “

0”

to “

15”

.

16. A method for unidirectional optical communication between a display and a camera observing the display, comprising:

using an aggregation technique such that an image sequence captured by the camera from the display is processed into a stabilized aggregate image to minimize flicker of the display;

displaying a pattern on the display to notify the camera that the display is prepared to transmit information;

displaying each symbol in a set of communication symbols in sequence on the display to define the communication symbols to the camera;

encoding information to be transmitted to the camera using the communication symbols;

displaying the encoded information on the display for reception by the camera; and

decoding the encoded information received by the camera using the defined communication symbols,

wherein using the aggregation technique further comprises obtaining a maximum value of each color component for each pixel over the image sequence to produce the stabilized aggregate image.

17. The method of claim 16, further comprising determining a region of an image sequence obtained from the camera that is occupied by the display.