Performance Improvement in Spread Spectrum Image Watermarking Using Wavelets

Abstract

This paper investigates the scope of wavelets for performance improvement in spread spectrum image watermarking. Performance of a digital image watermarking algorithm, in general, is determined by the visual invisibility of the hidden data (imperceptibility), reliability in the detection of the hidden information after various common and deliberate signal processing operations (robustness) applied on the watermarked signals and the amount of data to be hidden (payload) without affecting the imperceptibility and robustness properties. In this paper, we propose a few spread spectrum (SS) image watermarking schemes using discrete wavelet transform (DWT), biorthogonal DWT and M -band wavelets coupled with various modulation, multiplexing and signaling techniques. The performance of the watermarking methods are also reported along with the relative merits and demerits.

Spread Spectrum Watermarking: Principles and Applications in Fading Channel

“…To increase payload in SS watermarking, the concept of M-ary modulation and code division multiple access (CDMA) are used (Maity & Kundu, 2007a). It has been shown that performance improvement in former makes it impractical in real-time due to the exponential increase in computation cost with large M-values, while CDMA based algorithms are interference limited (Maity & Kundu, 2004;Maity & Kundu, 2011). A modified M-ary watermark decoding algorithm using a tree-structure was proposed that reduces the number of correlators to 2 log 2 M (Xin & Pawlak, 2008).…”

“…In SS watermarking, the bits composing the desired message are modulated using spreading code patterns and are added to the host (original) signal. The message may consist of a random number with zero mean and unit variance like an independent and identically distributed (i.i.d) Gaussian sequence, a string of binary data (binary signaling) or a group of symbols where each symbol consists of combination of binary data (M-ary signaling) (Malver & Florencio, 2003;Maity & Kundu, 2011). The associated problems in SS watermark system are the effect of host signal interference (HSI), poor payload due to spectrum spreading and poor detection performance for the widely used correlator in presence of non-stationary fading attack i.e.…”

Fuzzy-GA hybridization in M-band wavelets for collusion resilient optimized SS watermarking

“…In SS watermarking, the bits to be embedded consist of a random number with zero mean and unit variance i.e. an independently identically distributed (i.i.d) Gaussian sequence [5], a string of binary data (binary signaling) or a group of symbols where each symbol consists of combination of binary data (M-ary signaling) [6]. The associated problems in SS watermark system are the effect of host signal interference (HSI), poor payload due to spectrum spreading and poor detection performance for the widely used correlator in presence of non-stationary fading attack i.e.…”

“…The associated problems in SS watermark system are the effect of host signal interference (HSI), poor payload due to spectrum spreading and poor detection performance for the widely used correlator in presence of non-stationary fading attack i.e. gain attack [6], [7].…”

“…To increase payload in SS watermarking, the concept of Å-ary modulation and code division multiple access (CDMA) are also used [6]. It has been shown that performance improvement in former makes it impractical in real-time due to the exponential increase in computation complexity with large Å-values, while CDMA based algorithms are interference limited [6].…”