System identification based on quantized observations requires either approximations of the quantization noise, leading to suboptimal algorithms, or dedicated algorithms taylored to the quantization noise properties. This contribution studies fundamental issues in estimation that relate directly to the core methods in system identification. As a first contribution, results from statistical quan...

In this paper, a new secure watermarking scheme for color image is proposed. It splits the watermark into two shares using (2, 2)threshold Visual Cryptography Scheme (V CS) with Adaptive Order Dithering technique and embeds one share into high textured subband of Luminance channel of the color image. The other share is used as the key and is available only with the super-user or the author of t...

In this paper we discuss the effects of applying inverse halftoning before detection of watermark in halftoned images. Inverse halftoning can be thought of as another distortion to the watermarked image. We will show an enhancement in watermark detector performance if inverse halftoning is used on smooth error diffused images and a deterioration in performance if inverse halftoning is used on h...

Error di usion ordered dither and patterning are well known digital halftoning tech niques each with its advantages and disadvantages Error di usion is known for correlated artifacts looking like zebra stripes Images produced by ordered dither and patterning su er from arti cial contours in slowly varying regions of pictures Use of ordered matrices by both ordered dither and patterning results ...

The signals ttansmitted by Block II satellites of the Global Positioning System (GPS) can be degraded to limit the highest accuracy of the system (10m or better point positioning) to authorized users. This mode of degraded operation is called "Selective Availability" (S/A). SlA involves the degradation in the quality of broadcast orbits and satellite clock dithering. We monit<X'ed the didtered ...

Source-based dithering is a set of techniques designed to maximize the performance of real-time networked digital video systems that encode and decode video entirely in software. Usually frame grabber hardware presents frames in a 24 bit per pixel (bpp) format. However, most hosts are only equipped with single or eight bit deep displays and thus the color depth of the video must be reduced at s...

Subtractive dithered quantizers are examined to minimize the signal-band dither power. The design of finite impulse response(FIR) filters that shape most of the ditherpower out of the signal band while maintaining the benefits of dithering are dealt with in detail. Simulation results for lowmedium resolution quantizers are presented to highlight the overall design consideration.

DEVS (Discrete Event Systems Specification) models are widely employed for simulation-based performance evaluation of discrete event systems. Performance modeling of such a system requires a pruning of a set of components, or objects, within the system in its subset which are eventually transformed into simulation models. Such modeling is objective-driven in that simulation models may be abstra...