The accurate assessment of nutrition information is a challenging task, but crucial for people with certain diseases, such as diabetes. An important part of the assessment of nutrition information is portion estimation, i.e. volume estimation. Given the volume and the food type, the nutrition information can be computed on the basis of the food type specific nutrition density. Recently mobile devices with depth sensors have been made available for the public (Google's project tango platform). In this work, an app for mobile devices with a depth sensor is presented which assists users in portion estimation. Furthermore, we present the design of a user study for the app and preliminary results.

Patients with Frozen Shoulder suffer from a decreased mobility and pain. Exercise-based physiotherapy is a common treatment and patients mostly perform the exercises at home. Correct exercise performance and compliance are the main issues in home-based therapy of Frozen Shoulder patients. To support patients diagnosed with Frozen Shoulder, a multimodal 3D smartphone app was designed, developed and evaluated. Additional to ten potential users, one physician, five physiotherapists, three computer scientists, two 3D artists and one HCI specialist were involved in the co-creation process. The app was evaluated by five patients during a three-week pilot study, which showed the feasibility of our approach. Exercise correctness, usage of multimodal instructions and user satisfaction were analyzed. Exercise correctness was nearly perfect and the interactive 3D animation was used for exercise instructions. Satisfaction using the app was rated very high according to SUS score. The results confirm that the co-creation process led to an effective, highly satisfactory and actually used system.

The workshop will focus on AR Glasses and how their new and unique interfaces change the way we use, develop, interact with and percept Augmented Reality. The main goal is to get a large amount of people interested in Augmented Reality Glasses to discuss particular topics of and issues with AR Glasses, and to understand what developers and users must change in the way they use AR on AR Glasses, compared to AR on smartphones, tablets and laptops.

Accurate assessment of nutrition information is an important part in the prevention and treatment of a multitude of diseases, but remains a challenging task. We present a novel mobile augmented reality application, which assists users in the nutrition assessment of their meals. The user sketches the 3D form of the food and selects the food type. The corresponding nutrition information is automatically computed.

In this work we propose a novel non-blind H.264/CAVLC structure-preserving substitution watermarking algorithm. The proposed watermarking algorithm enables extremely efficient watermark embedding by simple bit substitutions (substitution watermarking). The bit-substitutions change the motion vector differences of non-reference frames. Furthermore our watermarking algorithm can be applied in applications scenarios which require that watermarking preserves the length of the bitstream units (structure-preserving watermarking). The watermark detection works in the image domain and thus is robust to video format changes. The quality and robustness of the approach are in depth evaluated and analyzed, the quality evaluation is backed up by subjective evaluations. Comparison to the state-of-the-art indicates a superior performance of our watermarking algorithm.

JPEG2000 Part 2 allows the application of arbitrary wavelet decomposition structures (wavelet packet bases). Efficient anisotropic wavelet packet basis selection for the coding framework of JPEG2000 has been developed and evaluated. Previous work focused on isotropic wavelet packet basis selection algorithms for JPEG2000, which serves as basis for the performance of the assessment of anisotropic wavelet basis selection. Several cost functions are applied in a top-down anisotropic wavelet packet selection scheme. Our evaluations employ state-of-the-art quality assessment tools supplementary to PSNR evaluations.

Key-dependent Wavelet Packet Transforms (KDWPT) have been proposed for image encryption and especially for the joint application with the JPEG2000 compression framework. An assumed advantage of this compression integrated encryption scheme is its assumed negligible computational demand. In this work we analyze the assumption (KDWPT are lightweight compared to conventional encryption) both practically by experiments with state-of-the-art implementations and theoretically (by developing a proper model for the complexity of KDWPT).

Abstract We analyze and discuss encryption schemes for JPEG2000 based on the wavelet packet transform with a key-dependent subband structure. These schemes have been assumed to reduce the runtime complexity of encryption and compression. In addition to this "lightweight" nature, other advantages like encrypted domain signal processing have been reported. We systematically analyze encryption approaches based on key-dependent subband structures in terms of their impact on compression performance, their computational complexity and the level of security they provide as compared to more classical techniques. Furthermore, we analyze the prerequisites and settings in which the previously reported advantages actually hold and in which settings no advantages can be observed. As a final outcome it has to be stated that the compression integrated encryption approach based on the idea of secret wavelet packets can not be recommended.

Universal Multimedia Access (UMA) calls for solutions where content is created once and subsequently adapted to given requirements. With regard to UMA and scalability, which is required often due to a wide variety of end clients, the best suited codecs are wavelet based (like the MC-EZBC) due to their inherent high number of scaling options. However, most transport technologies for delivering videos to end clients are targeted toward the H.264/AVC standard or, if scalability is required, the H.264/SVC. In this paper we will introduce a mapping of the MC-EZBC bitstream to existing H.264/SVC based streaming and scaling protocols. This enables the use of highly scalable wavelet based codecs on the one hand and the utilization of already existing network technologies without accruing high implementation costs on the other hand. Furthermore, we will evaluate different scaling options in order to choose the best option for given requirements. Additionally, we will evaluate different encryption options based on transport and bitstream encryption for use cases where digital rights management is required.

Video encryption has been heavily researched in the recent years. This survey summarizes the latest research results on video encryption with a special focus on applicability and on the most widely-deployed video format H.264 including its scalable extension SVC. The survey intends to give researchers and practitioners an analytic and critical overview of the state-of-the-art of video encryption narrowed down to its joint application with the H.264 standard suite and associated protocols (packaging/streaming) and processes (transcoding/watermarking).

This paper discusses optimal wavelet packet basis selection within JPEG2000. Algorithms for rate-distortion optimal wavelet packet basis selection in JPEG2000 are presented and compared to more efficient wavelet packet basis selection schemes. Both isotropic and anisotropic wavelet packet bases are considered. For the first time, computationally efficient heuristics are compared to the best bases in the standardized coding framework of JPEG2000. For the first time, the maximum performance gains of custom wavelet packets in JPEG2000 can be assessed. The algorithms are evaluated on a wide range of highly textured image data.

Efficient rate-distortion optimal wavelet packet basis selection for the coding framework of JPEG2000 has been developed and evaluated. JPEG2000 Part 2 allows the application of arbitrary decomposition structures (wavelet packet bases). However, only a subset of all possible wavelet packet bases is permitted in the JPEG2000 standard. As we have developed a rate-distortion optimal wavelet packet basis selection algorithm, we can determine the cost of these restrictions for the first time. A further focus is on the efficient implementation of wavelet packet basis selection. The best basis selection in a rate-distortion sense is computationally feasible, yet not inexpensive. Several more efficient wavelet packet selection algorithms have been developed and are compared to the actually best solution. Our evaluations employ state-of-the-art quality assessment tools supplementary to PSNR evaluations.

This paper discusses optimal wavelet packet basis selection within JPEG2000. Two algorithms of Lagrangian rate distortion optimal wavelet packet basis selection for JPEG2000 are presented. The first and more conservative approach considers the JPEG2000 packet body data in the rate distortion optimization only, while the other technique additionally integrates packet header data. The algorithms are evaluated on the FVC2004 fingerprint databases and other textured image data. Results demonstrate that inclusion of header data information into rate distortion optimization leads to superior compression results. For the first time the maximum performance gains of custom isotropic wavelet packets in JPEG2000 can be assessed.

The impact of using different wavelet packet subband structures in JPEG2000 on the matching accuracy of a fingerprint recognition system is investigated. In particular, we relate rate-distortion performance as measured in PSNR to the matching scores as obtained by the recognition system. Employing wavelet packets instead of the dyadic wavelet transform turns out to be of advantage only in case of low bitrates (i.e. high compression rates). For such settings, the good performance of the WSQ structure is confirmed also in JPEG2000 and in particular we get better recognition accuracy using the WSQ structure as compared to the employment of a rate-distortion optimising subband selection approach

In this paper we investigate the applicability of different parts of the JPEG2000 codestream for authentication. Apart from the packet body different classes of information contained in the packet header are investigated. We report on experimental results obtained with a large test set of natural images to assess how discriminative and how sensitive each class of information is. Specific attacks against authentication schemes, that use selective hashing of either packet bodies (as proposed in literature) or packet headers, are presented.

An encryption approach for H.264/AVC and SVC is proposed. Although the bitstream (format stream) is encrypted with state-of-the-art symmetric ciphers, H.264/AVC and SVC compliance is preserved. Standard compliant encoder/decoder and conventional symmetric ciphers, e.g., in specialized hardware, can still be employed – a significant advantage compared to previous work. The approach is suitable for a wide range of application scenarios.

JPEG2000 encryption has become a widely discussed topic and quite a number of contributions have been made. However, little is known about JPEG2000 compression parameters and their influence on the security and performance of format, compliant encryption schemes. In this work, a thorough analysis of this topic is presented with a focus on format-compliant packet body encryption as sketched in the FCD 15444-8 (JPSEC). A proof for the reversibility of JPSEC format-compliant packet body encryption is given. As format-compliant packet body encryption preserves the JPEG2000 headers, which severely compromises the security, we additionally discuss packet header encryption with a special focus on format compliance and the influence of compression parameters on these schemes. Copyright © 2007 Dominik Engel et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Format-compliant encryption of JPEG2000 has attracted researchers for several years. Most benefits of format-compliant encryption result from the preservation of code-stream features, such as scalability. The possibility of reducing the complexity of encryption and to realize transparent encryption schemes are among the additional features of format-compliant selective encryption. Wu and Deng have proposed a format-compliant iterative encryption scheme for JPEG2000 on a CCP basis. In this paper we discuss whether it is possible to extend this approach to packet bodies and give an exact formula for the expected computational effort. The theoretical results are cross-verified by an experimental survey