초록 ▼

A visual code system wherein camera-equipped mobile phones (or similar devices, such as wireless PDAs) are used to identify and decode images that contain one or more "visual codes." By recognizing a code tag, the device can determine a bit pattern or an integer number encoded in the tag (the code v

A visual code system wherein camera-equipped mobile phones (or similar devices, such as wireless PDAs) are used to identify and decode images that contain one or more "visual codes." By recognizing a code tag, the device can determine a bit pattern or an integer number encoded in the tag (the code value), the targeted object or image element, as well as additional parameters, such as the viewing angle of the camera. Code recognition is performed on the mobile device itself. When the mobile device is equipped with a wireless communication channel, it can be used to retrieve online content or to access information on the Internet based on the sensed code and its parameters. The retrieved content can then be presented on the mobile device.

대표청구항 ▼

I claim: 1. A method for decoding a visual code comprising: capturing a visual code image comprising at least one visual code utilizing a mobile device equipped with a digital camera; grayscaling said visual code image; thresholding said visual code image; identifying regions of interest in said vi

I claim: 1. A method for decoding a visual code comprising: capturing a visual code image comprising at least one visual code utilizing a mobile device equipped with a digital camera; grayscaling said visual code image; thresholding said visual code image; identifying regions of interest in said visual code image; calculating the orientations and shapes of the identified regions of interest within said visual code image; locating said at least one visual code within said visual code image; computing a first projective mapping of said at least one visual code from a visual code image coordinate system to a visual code coordinate system; computing a second projective mapping of said at least one visual code from the visual code coordinate system to the visual code image coordinate system; computing a rotation angle of said at least one visual code located in said visual code image; computing horizontal and vertical tilting values of said at least one visual code; computing a distance of said at least one visual code from said mobile device; reading encoded bits in said at least one visual code to produce at least one decoded value; and displaying information on the mobile device associated with at least one of the identified regions of interest based on at least one of the at least one decoded value, the first projective mapping, the second projective mapping, the rotation angle, the horizontal tilting value, the vertical tilting value, and the distance. 2. A method for decoding a visual code according to claim 1, further comprising correcting said visual code image for radial lens distortion prior to grayscaling said visual code image. 3. A method for decoding a visual code according to claim 1, further comprising performing error detection on said at least one visual code. 4. A method for decoding a visual code according to claim 3, wherein said error detection is performed utilizing Reed-Solomon error detection. 5. A method for decoding a visual code according to claim 1, wherein said at least one visual code comprises three cornerstones, a small guide bar, and a large guide bar. 6. A method for decoding a visual code according to claim 5, wherein an individual visual code is located by identifying said cornerstones, said small guide bar, and said large guide bar. 7. A method for decoding a visual code according to claim 5, wherein said small guide bar and said large bar are identified by locating regions of said visual code image which have an axis ratio within a predetermined range. 8. A method for decoding a visual code according to claim 5, wherein said three cornerstones and said large guide bar are located at position (0,0,)(10,0), and (0,10), and wherein the center of said large guide bar is located at position (8,10) in said visual code coordinate system. 9. A method for decoding a visual code according to claim 5, wherein multiple visual codes are arranged in a grid to store data across multiple visual codes and further comprising identifying said grid of codes. 10. A method for decoding a visual code according to claim 1, wherein said at least one visual code comprises three cornerstones, a small guide bar, and a large guide bar, and wherein an orientation of said small guide bar and said large guide bar are utilized when computing the rotation angle of said at least one visual code, computing the distance of said at least one visual code, and computing the tilting values of said at least one visual code. 11. A method for decoding a visual code according to claim 1, wherein grayscaling said visual code image is performed by calculating the value of each grayscale pixel by averaging the value of the red and green pixels. 12. A method for decoding a visual code according to claim 11, wherein said grayscale visual code image is converted to a black and white image using a weight-moving average algorithm. 13. A method for decoding a visual code according to claim 1, wherein at least one from the group comprising the rotation angle, horizontal tilting value, vertical tilting angle, and distance of said at least one visual code is utilized to select options from a menu. 14. A method for decoding a visual code according to claim 1, wherein said decoding occurs in real-time. 15. A method for decoding a visual code according to claim 14, further comprising overlaying a graphic over an image displayed on a screen of the camera wherein said overlayed graphic is geometrically aligned with objects in the image as the mobile device moves and the orientation of said at least one visual code changes. 16. A method for decoding a visual code according to claim 1, wherein the displayed information is retrieved from a database. 17. A method for decoding a visual code according to claim 16, wherein said database associates different uniform resource locators with the displayed information. 18. A method for decoding a visual code according to claim 1, further comprising selecting entries from a form by altering the orientation of said mobile device to said at least one visual code. 19. A method for decoding a visual code according to claim 1, wherein the displayed information is at least one of a movie plot outline, a video clip, an audio file, and a movie review. 20. A method for decoding a visual code according to claim 1, wherein said at least one visual code is printed utilizing infrared ink and wherein said digital camera captures said at least one visual code as an at least one infrared visual code. 21. A method for decoding a visual code according to claim 1, wherein a target point, expressed in the visual code coordinate system of an image displayed on a screen of the camera, is utilized as a parameter to select an entry from a database. 22. A method for decoding a visual code according to claim 1, wherein pointing said digital camera at said at least one visual code is facilitated by a cross hair that is displayed on a screen of said mobile device. 23. A method for decoding a visual code according to claim 22, wherein said screen of said mobile device is a touch screen, and wherein the position of said cross hair may be specified by using a stylus to specify a target point. 24. A computer-readable medium storing computer-executable instructions that, when executed by a processor, cause the processor to perform a method for decoding a visual code, the method comprising: capturing a visual code image comprising at least one visual code utilizing a mobile device equipped with a digital camera; grayscaling said visual code image; thresholding said visual code image; identifying regions of interest in said visual code image; calculating the orientations and shapes of the identified regions of interest within said visual code image; locating said at least one visual code within said visual code image; computing a first projective mapping of said at least one visual code from a visual code image coordinate system to a visual code coordinate system; computing a second projective mapping of said at least one visual code from the visual code coordinate system to the visual code image coordinate system; computing a rotation angle of said at least one visual code located in said visual code image; computing horizontal and vertical tilting values of said at least one visual code; computing a distance of said at least one visual code from said mobile device; reading encoded bits in said at least one visual code to produce at least one decoded value; and displaying information on the mobile device associated with at least one of the identified regions of interest based on at least one of the at least one decoded value, the first projective mapping, the second projective mapping, the rotation angle, the horizontal tilting value, the vertical tilting value, and the distance. 25. A device for decoding a visual code, comprising: a memory; a digital camera; a display; and a processor in communication with the memory, the digital camera, and the display; wherein the processor captures a visual code image comprising at least one visual code; grayscales said visual code image; thresholds said visual code image; identifies regions of interest in said visual code image; calculates the orientations and shapes of the identified regions of interest within said visual code image; locates said at least one visual code within said visual code image; computes a first projective mapping of said at least one visual code from a visual code image coordinate system to a visual code coordinate system; computes a second projective mapping of said at least one visual code from the visual code coordinate system to the visual code image coordinate system; computes a rotation angle of said at least one visual code located in said visual code image; computes horizontal and vertical tilting values of said at least one visual code; computes a distance of said at least one visual code from said mobile device; reads encoded bits in said at least one visual code to produce at least one decoded value; and displays information associated with at least one of the identified regions of interest based on at least one of the at least one decoded value, the first projective mapping, the second projective mapping, the rotation angle, the horizontal tilting value, the vertical tilting value, and the distance.