IDENTIFYING AND REDRESSING SHADOWS IN CONNECTION WITH DIGITAL WATERMARKING AND FINGERPRINTING; AND DYNAMIC SIGNAL DETECTION ADAPTED BASED ON LIGHTING INFORMATION

摘要

Shadow detection in images captured by cell phones and cameras relates to digital watermarking, steganographic data hiding and fingerprinting involves identifying a shadow cast by a camera on a subject being imaged. Using a processor, redress the shadow in connection with reading a digital watermark from imagery captured of the subject or calculating a fingerprint from the imagery captured of the subject. Identify a shadow cast by a cell phone on a subject and using a processor, determine a proximity of the camera to the subject based on an analysis of the shadow. Obtain lighting information associated with image or video capture and adapt a signal identification process to deemphasize signal contribution of the blue channel when the lighting information is associated with incandescent lighting; and using a processor, analyze image or video data to derive identifying information therefrom. Of course, other claims and combinations are provided too.