Embedding information in an image for fast retrieval

摘要

A binary bit-string is encoded in a circular image. The circular image encodes substrings of the bit-string in sectors of the circular image and includes redundant bits, error correcting codes, and metadata pertaining to the encoding scheme. To encode the bit-strings, a circular image is generated that includes a center ring and a first ring. Outward from the first ring, additional rings represent bits in the bit-string according to the width of each ring. The exterior of the image includes an outer boundary ring. The width of the boundary rings is used to define the widths representing the value of each ring. To extract a bit-string from an image, the center of the circular image is identified and a direction is selected to evaluate the image outward, determining the boundaries of each ring. The boundaries are analyzed to determine the width of each ring and the encoded bit values.

主权项

1. A method for extracting a bit-string from an image, comprising:
capturing the image of an encoded bit-string using a camera-equipped device; grayscaling the captured image; locating a center of the captured image; determining a direction of travel in the image from the center of the captured image; determining a first thickness corresponding to a value of 0 and a second thickness corresponding to a value of 1; detecting rings in the captured image along the direction of travel from the center, and for each ring:
measuring a thickness of the ring, and applying clustering techniques to identify it as having the first thickness or the second thickness; andappending to a bit-string a value of 0 if the ring has the first thickness corresponding to the value of 0; or appending to the bit-string a value of 1 if the ring has the second thickness corresponding to the value of 1; and storing the completed bit-string.