Image Integrity Verification Using Content-Based Watermarking

Digital watermarking is a technique to insert an information-carrying digital signature into a digital media so that the signature can be extracted for variety of purposes including ownership authentication and content verification. In recent years, the popularity of the Internet and increase of sophisticated image processing tools commercially available today have created opportunities for malicious parties to intercept images, modify its content, and then transmit the forgeries to their respective receivers, where alterations resemble closely to the work of professionals and are undetectable by the human eye. For this reason, in order to reduce the constant proliferation and threats for digital media in the World Wide Web, digital watermarking is one of the crucial techniques to protect the contents of products in digital form and enable copyright or ownership information to be embedded into the multimedia data. The purpose of this study was to examine the weaknesses against common watermarking attacks of blockwise independent and content-based watermarking algorithms for image integrity verification and implement a new and more secure invisible fragile watermarking technique for color or grayscale images that increases the message digest size from the proposed 64 to 128 bits using the same small-size blocks and maintaining accurate localization of image changes. Our watermarking technique is capable to detect any changes made to the image since the time it was stamped, any changes to the pixel values and also to the dimensions of the image will be automatically detected and localized. Our scheme consists of a watermark insertion process that uses a private key to embed a watermark image into a cover image, and a watermark extraction process that uses a public key to extract the watermark from the watermarked image. The embedded watermark can only be extracted by someone who has possession of a proper verification key. This implies that someone who does not have a valid key will not be able to forge a watermark that will pass undetected. Finally, our technique provides means of ensuring data integrity; adds more security to the contents of digital media and allows recipients of an image to verify its authenticity with ease as well as display the ownership information embedded within an image.Computer Science Departmen

Improved characteristics of near-band-edge and deep-level emissions from ZnO nanorod arrays by atomic-layer-deposited Al2O3 and ZnO shell layers

We report on the characteristics of near-band-edge (NBE) emission and deep-level band from ZnO/Al2O3 and ZnO/ZnO core-shell nanorod arrays (NRAs). Vertically aligned ZnO NRAs were synthesized by an aqueous chemical method, and the Al2O3 and ZnO shell layers were prepared by the highly conformal atomic layer deposition technique. Photoluminescence measurements revealed that the deep-level band was suppressed and the NBE emission was significantly enhanced after the deposition of Al2O3 and ZnO shells, which are attributed to the decrease in oxygen interstitials at the surface and the reduction in surface band bending of ZnO core, respectively. The shift of deep-level emissions from the ZnO/ZnO core-shell NRAs was observed for the first time. Owing to the presence of the ZnO shell layer, the yellow band associated with the oxygen interstitials inside the ZnO core would be prevailed over by the green luminescence, which originates from the recombination of the electrons in the conduction band with the holes trapped by the oxygen vacancies in the ZnO shell

Video copy detection by fast sequence matching

ABSTRACT Sequence matching techniques are effective for comparing two videos. However, existing approaches suffer from demanding computational costs and thus are not scalable for large-scale applications. In this paper we view video copy detection as a local alignment problem between two frame sequences and propose a two-level filtration approach which achieves significant acceleration to the matching process. First, we propose to use an adaptive vocabulary tree to index all frame descriptors extracted from the video database. In this step, each video is treated as a "bag of frames." Such an indexing structure not only provides a rich vocabulary for representing videos, but also enables efficient computation of a pyramid matching kernel between videos. This vocabulary tree filters those videos that are dissimilar to the query based on their histogram pyramid representations. Second, we propose a fast edit-distance-based sequence matching method that avoids unnecessary comparisons between dissimilar frame pairs. This step reduces the quadratic runtime to a linear time with respect to the lengths of the sequences under comparison. Experiments on the MUSCLE VCD benchmark demonstrate that our approach is effective and efficient. It is 18X faster than the original sequence matching algorithms. This technique can be applied to several other visual retrieval tasks including shape retrieval. We demonstrate that the proposed method can also achieve a significant speedup for the shape retrieval task on the MPEG-7 shape dataset

Anthropomorphism of AI-based Intelligent Customer Service, and Its Affective and Behavioral Consequences

Recently, as many users turn to social media to interact with service providers, organizations apply Artificial intelligence (AI) to improve the efficiency and effectiveness of the operation. This type of customer service system is called intelligent customer service (ICS) which one of the most commonly adopted tools is chatbot. Since chatbot is AI-empowered, whether this system can effectively interact with customers and solve their problems is critical. However, the quality of ICS has received significant attention recently, and a lack of systematic study on the outcomes of anthropomorphism leaves this question unanswered in an ICS context. Based on a cognitive-affective-behavioral framework, this study attempts to understand whether anthropomorphism can promote desired behaviors (including usage and citizen-ship behaviors) through enhancing affective out-comes, such as satisfaction and identity. Data collected from 183 chatbot-ICS users, this study illustrates how anthropomorphism can increase quality, enhance satisfaction and identity. Furthermore, we also show that satisfaction and identity lead to further usage and citizenship behaviors. This highlights the importance of increasing anthropomorphism for the chatbot-ICS

Land Subsidence Caused by Groundwater Exploitation in Yunlin, Taiwan

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive