Digital watermarking image signals on-chip
The disclosure describes methods and apparatus for providing digital watermarks or steganographic indicia in image or video data. One implementation embeds digital watermarks on-chip with respect to a CMOS or CCD image array. Some implementations introduce a watermark component during image capture, the watermark being introduced through variations in physical characteristics of a set of pixels. Other implementations are provided and claimed as well.
1. A CMOS imager comprising: a plurality of pixels arranged in columns and rows, wherein each of the pixels includes: a photodetector; a color filter portion; and a microlens; and a communications bus to selectively read out image data from the plurality of pixels, wherein the plurality of pixels includes at least a first set of pixels, with the first set of pixels having physical properties so as to introduce a hidden or concealed digital watermark component to image data during image capture by the CMOS imager, wherein each of the plurality of pixels communicates with different amplifiers, and wherein the physical properties comprise varied gain of different amplifiers associated with the first set of pixels.