Uni-directional Hybrid Distributed Video Coding With Macroblock Classification

Tammam Tillo,Hoyoung Lee,Byeungwoo Jeon 대한전자공학회 2009 ITC-CSCC :International Technical Conference on Ci Vol.2009 No.7

Distributed Video Coding (DVC) is a new coding paradigm suitable for extremely low complexity video encoders. This makes it suitable for limited resources applications such as sensor network. Wyner-Ziv video coding, the most representative method in DVC uses channel coding, such as turbo code or LDPC code, to reconstruct a frame based on side information. It is important to transmit just right amount of channel coded data, and this problem has been generally tackled by using a feedback channel. In this paper, we propose a hybrid distributed video coding approach which combines motion compensated prediction and Wyner-Ziv video coding. This allows to accurately estimate the required channel code rate, thus eliminating the feedback channel. Experimental results indicate that the proposed method achieves good performance while maintaining low complexity.

Enhanced oxygen evolution reaction over glassy carbon electrode modified with NiOx and Fe3O4

Reham Helmy Tammam,Amany Mohamed Fekry,Mahmoud Mohamed Saleh 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.11

Magnetite iron oxide (Fe3O4)/nickel oxide (NiOx) modified glassy carbon (GC) electrode shows enhancement of oxygen evolution reaction (OER) compared to GC electrode modified with single NiOx or Fe3O4 nanoparticles. Many techniques such as linear and cyclic sweep voltammetry, electrochemical impedance spectroscopy (EIS) have been employed. Field-emission scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) are both used for characterization of the electrocatalysts. Effect of loading amount of both NiOx and Fe3O4 and the order of deposition on the OER was studied. A significant improvement of the electrocatalytic properties of the Fe3O4/NiOx binary catalyst modified GC is obtained when NiOx is electrodeposited on GC/Fe3O4 (i.e. GC/Fe3O4/NiOx) compared to GC/NiOx/Fe3O4 (where NiOx is deposited first on the GC then Fe3O4). The use of GC/Fe3O4/NiOx (where Fe3O4 is deposited first on the GC then NiOx) for OER in alkaline solution support higher currents and consequently negative shifts of the onset potential of OER compared to that of GC/NiOx or GC/Fe3O4. The obtained electrochemical impedance parameters confirmed the above conclusions. Tafel parameters confirm the superior activity of GC/Fe3O4/ NiOx and give insight into the mechanism of the OER on the above electrodes.

포커스 : "무슬림동포단"의 변천

후삼탐맘 ( Hussam Tammam ) 한국민족연구원 2005 민족연구 Vol.0 No.24

Concurrency Conflicts Resolution for IoT Using Blockchain Technology

Morgan, Amr,Tammam, Ashraf,Wahdan, Abdel-Moneim International Journal of Computer ScienceNetwork S 2021 International journal of computer science and netw Vol.21 No.7

The Internet of Things (IoT) is a rapidly growing physical network that depends on objects, vehicles, sensors, and smart devices. IoT has recently become an important research topic as it autonomously acquires, integrates, communicates, and shares data directly across each other. The centralized architecture of IoT makes it complex to concurrently access control them and presents a new set of technological limitations when trying to manage them globally. This paper proposes a new decentralized access control architecture to manage IoT devices using blockchain, that proposes a solution to concurrency management problems and enhances resource locking to reduce the transaction conflict and avoids deadlock problems. In addition, the proposed algorithm improves performance using a fully distributed access control system for IoT based on blockchain technology. Finally, a performance comparison is provided between the proposed solution and the existing access management solutions in IoT. Deadlock detection is evaluated with the latency of requesting in order to examine various configurations of our solution for increasing scalability. The main goal of the proposed solution is concurrency problem avoidance in decentralized access control management for IoT devices.

Hybrid Wyner-Ziv Video Coding with No Feedback Channel

Hoyoung Lee,Tillo Tammam,Byeungwoo Jeon 대한전자공학회 2016 IEIE Transactions on Smart Processing & Computing Vol.5 No.6

In this paper, we propose a hybrid Wyner-Ziv video coding structure that combines conventional motion predictive video coding and Wyner-Ziv video coding to eliminate the feedback channel, which is a major practical problem in applications using the Wyner-Ziv video coding approach. The proposed method divides a hybrid frame into two regions. One is coded by a motion predictive video coder, and the other by the Wyner-Ziv coding method. The proposed encoder estimates side information with low computational complexity, using the coding information of the motion predictive coded region, and estimates the number of syndrome bits required to decode the region. The decoder generates side information using the same method as the encoder, which also reduces the computational complexity in the decoder. Experimental results show that the proposed method can eliminate the feedback channel without incurring a significant rate-distortion performance loss.

Multiple Description Coding for H.264/AVC With Redundancy Allocation at Macro Block Level

Chunyu Lin,Tillo, Tammam,Yao Zhao,Byeungwoo Jeon IEEE 2011 IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDE Vol.21 No.5

<P>In this paper, a novel multiple description video coding scheme is proposed to insert and control the redundancy at macro block (MB) level. By analyzing the error propagation paths, the relative importance of each MB is determined. The paths, in practice, depend on both the video content and the adopted video coder. Considering the relative importance of the MB and the network status, an unequal protection for the video data can be realized to exploit the redundancy effectively. In addition, a simple and effective approach is introduced to tune the quantization parameter for the variable rate coding case. The whole scheme is implemented in H.264/AVC by employing its coding options, thus generating descriptions that are compatible with the baseline profile and extended profile of H.264/AVC. Due to its general property, the proposed approach can be employed for other hybrid video codecs. The results demonstrate the advantage of the proposed approach over other H.264/AVC multiple description schemes.</P>

Texture Plus Depth Video Coding Using Camera Global Motion Information

Cheng, Fei,Tillo, Tammam,Xiao, Jimin,Jeon, Byeungwoo IEEE 2017 IEEE transactions on multimedia Vol.19 No.11

<P>In video coding, traditional motion estimation methods work well for videos with camera translational motion, but their efficiency drops for other motions, such as rotational and dolly motions. In this paper, a motion-information-based three-dimensional (3D) video coding method is proposed for texture plus depth 3D video. The synchronized global motion information of the camera is obtained to assist the encoder improve its rate-distortion performance by projecting the temporal neighboring texture and depth frames into the position of the current frame, using the depth and camera motion information. Then, the projected frames are added into the reference buffer list as virtual reference frames. As these virtual reference frames could be more similar to the current to-be-encoded frame than the conventional reference frames, the required bits to represent the residual will be reduced. The experimental results demonstrate that the proposed scheme enhances the coding performance for all camera motion types and for various scene settings and resolutions using H.264 and HEVC standards, respectively. With the computer graphic sequences, for H.264, the average gain of texture and depth coding are up to 2 dB and 1 dB, respectively. For HEVC and HD resolution sequences, the gain of texture coding reaches 0.4 dB. For realistic sequences, up to 0.5 dB gain (H.264) is achieved for the texture video, while up to 0.7 dB gain is achieved for the depth sequences.</P>

Depth Map Coding Using Histogram-Based Segmentation and Depth Range Updating

( Chunyu Lin ),( Yao Zhao ),( Jimin Xiao ),( Tammam Tillo ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.3

In texture-plus-depth format, depth map compression is an important task. Different from normal texture images, depth maps have less texture information, while contain many homogeneous regions separated by sharp edges. This feature will be employed to form an efficient depth map coding scheme in this paper. Firstly, the histogram of the depth map will be analyzed to find an appropriate threshold that segments the depth map into the foreground and background regions, allowing the edge between these two kinds of regions to be obtained. Secondly, the two regions will be encoded through rate distortion optimization with a shape adaptive wavelet transform, while the edges are lossless encoded with JBIG2. Finally, a depth-updating algorithm based on the threshold and the depth range is applied to enhance the quality of the decoded depth maps. Experimental results demonstrate the effective performance on both the depth map quality and the synthesized view quality.

Slow Digestible Starch in Native Pea Starch (Pisum sativum L.) Lowers Glycemic Response with No Adverse Effects on Gastrointestinal Symptoms in Healthy Adults

Daniel Wils,Fabrice Desailly,Caroline Perreau,Sophie Grard,Pariyarath Sangeetha Thondre,Lis Ahlstrom,Jonathan Tammam 한국식품영양과학회 2023 Journal of medicinal food Vol.26 No.10

Diabetes prevalence achieved 470B in 2021. Diabetics are looking for foods that allow them to better managethe postprandial glycemia. Owing to its large amylose fraction, pea starch may contribute to formulate recipes with a lowerglycemic index (GI). This study measured the rapidly, slowly digested and resistant fractions in pea starch and in a powdermix recipe. Starch fractions were determined according to the Englyst methodology. A nonblind repeat measure crossoverdesign trial in healthy humans was used to study the GI of pea starch and maltodextrin powder mix recipes against glucose. Gastrointestinal symptoms were measured. Thirteen healthy volunteers aged 18–60 years with body mass index <30 kg/m2 andfasting blood glucose <6.1 mmol/L participated in the study. They consumed 25 g available carbohydrate portions of the testproducts. Blood glucose was measured at -5 and 0 min before consumption till 180 min after starting to eat. The slowdigestible starch (SDS) content of native pea starch was 30% of the total starch content. The pea-based powder mix recipecontained 25% SDS in comparison with 9% for the maltodextrin-based recipe. The glucose response after pea starch wassignificantly lower compared with maltodextrin. The glucose response after pea starch recipe was significantly lower comparedwith maltodextrin recipe. There was no significant difference in mean scores for well-being and gastrointestinalsymptoms after consumption of pea starch and maltodextrin or between the two recipes. In conclusion, this study hasdemonstrated the presence of high SDS content in pea starch, which reduced postprandial glycemic response compared withmaltodextrin. The pea starch recipe did not induce any negative gastrointestinal symptoms. Pea starch may, therefore, prove tobe a beneficial ingredient in developing food products for improving glycemic control without undesirable side effects.