Sparse modulation for robust signaling and synchronization

摘要

Sparse signal modulation schemes encode a data channel on a host image in a manner that is robust, flexible to achieve perceptual quality constraints, and provides improved data capacity. The host image is printed by any of a variety of means to apply the image, with sparse signal, to an object. After image capture of the object, a decoder processes the captured image to detect and extract data modulated into the sparse signal. The sparse signal may incorporate implicit or explicit synchronization components, which are either formed from the data signal or are complementary to it.

主权项

1. A method for inserting a sparse, variable data carrying signal into a digital image, the method comprising:
providing a first signal component, the first signal component facilitating a synchronization function of the sparse, variable data carrying signal, and comprising first signal component values at coordinates within a two-dimensional block; providing a second signal component, the second signal component being modulated to carry a variable data signal, and comprising second signal component values at coordinates within the two-dimensional block; combining the first signal component and the second signal component to produce the sparse, variable data carrying signal by setting sparse elements at coordinates within the two-dimensional block where the first signal component values and the second signal component values provide compatible modulation of the digital image; and inserting the sparse, variable data carrying signal into at least a first digital image layer or a first digital image channel of the digital image.