Image Fragile Watermarking through Quaternion Linear Transform in Secret Space

Abstract

Abstract:In this paper, we apply the quaternion framework for color images to a fragile watermarking algorithm with the objective of multimedia integrity protection (Quaternion Karhunen-Loève Transform Fragile Watermarking (QKLT-FW)). The use of quaternions to represent pixels allows to consider the color information in a holistic and integrated fashion. We stress out that, by taking advantage of the host image quaternion representation, we extract complex features that are able to improve the embedding and verification of fragile watermarks. The algorithm, based on the Quaternion Karhunen-Loève Transform (QKLT), embeds a binary watermark into some QKLT coefficients representing a host image in a secret frequency space: the QKLT basis images are computed from a secret color image used as a symmetric key. A computational intelligence technique (i.e., genetic algorithm) is employed to modify the host image pixels in such a way that the watermark is contained in the protected image. The sensitivity to image modifications is then tested, showing very good performance.

Hide45: A Method for Optimal Payload Data Hiding in Base45 Encoded Strings

“…From these figures it may be observed that for the distributions having a steepest start (for example, the MP3 file type distribution) there is a bigger gain in assigning a variable number of bits to every symbol: this is due to the fact that when there are symbols more frequent than others then allocating more bits to them increases the average payload (2).…”

“…Digital watermarking and steganography are part of the field of data hiding where some piece of information is stored in digital objects for various purposes ranging from simple information saving to copyright protection, from integrity protection or origin authentication to covert communication [1]. The digital objects involved in data hiding may be of any type, like images [2][3][4], audio files [5,6], movies [7][8][9], 3D models [10][11][12], neural networks [13][14][15][16], and textual data [17][18][19].…”

“…It is obvious that the 25,589 sequences must be assigned to the highest frequency binary configurations maximizing (2). Another way to write constraint (3) is to look only at the unused sequences; if any configuration i is assigned n i bits, it requires in total 2 n i − 1 extra configurations excluding itself.…”

Applying Quaternions to Recognize Hidden Details in Images: Rothko as a Case Study

“…The use of quaternions to represent pixels was previously considered in [12][13][14], which allows for consideration of the color information in a holistic and integrated fashion. In this manuscript, we use the quaternion algebraic structure for pattern recognition.…”

Robust and Secure Zero-Watermark Architecture With Arnold and Phase Transformation

“…Such interventions might encompass nuanced pixel value manipulations or orchestrated bit position alterations. The trade-off, however, is a somewhat reduced armor against attacks, rendering this methodology particularly suited for unearthing telltale signs of unauthorized tampering [10], [11].…”