Patent attributes
Watermarks and related machine-readable coding techniques are used to embed data within the information content on object surfaces. These techniques may be used as a substitute for (or in combination with) standard machine-readable coding methods such as bar codes, magnetic stripes, etc. As such, the coding techniques extend to many applications, such as linking objects with network resources, retail point of sale applications, object tracking and counting, production control, object sorting, etc. Object message data, including information about the object, machine instructions, or an index, may be hidden in the surface media of the object. An object messaging system includes an embedder and reader. The embedder converts an object message to an object reference, and encodes this reference in a watermarked signal applied to the object. The reader detects the presence of a watermark and decodes the watermark signal to extract the object reference.