• Title/Summary/Keyword: H.264 Standard

Search Result 272, Processing Time 0.021 seconds

2.2-inch QCIF+ a-Si TFT-LCD using Integrated Row Driver Circuits (Row Driver 회로가 집적된 2.2-inch QCIF+ a-Si TFT-LCD)

  • Yun, Y.J.;Han, S.W.;Jung, C.G.;Chung, K.H.;Kim, H.S.;Kim, S.Y.;Lim, Y.J.
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.18 no.3
    • /
    • pp.264-268
    • /
    • 2005
  • A 2.2-inch QCIF+(176${\times}$RGB${\times}$220) TFT-LCD with integrated row driver was developed using a standard amorphous silicon TFT technology. At low temperature, the integrated row driver operation is dramatically effected by the electron drift mobility reduction(■50 %) and the threshold voltage shift (■1V) of the a-Si TFT. We studied the dependency of circuit design and found that higher on-current circuit is important to guarantee good operation in wide temperature range.

Fast Quadtree Structure Decision for HEVC Intra Coding Using Histogram Statistics

  • Li, Yuchen;Liu, Yitong;Yang, Hongwen;Yang, Dacheng
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.9 no.5
    • /
    • pp.1825-1839
    • /
    • 2015
  • The final draft of the latest video coding standard, High Efficiency Video Coding (HEVC), was approved in January 2013. The coding efficiency of HEVC surpasses its predecessor, H.264/MPEG-4 Advanced Video Coding (AVC), by using only half of the bitrate to encode the same sequence with similar quality. However, the complexity of HEVC is sharply increased compared to H.264/AVC. In this paper, a method is proposed to decrease the complexity of intra coding in HEVC. Early pruning and an early splitting strategy are applied to the quadtree structure of coding tree units (CTU) and residual quadtree (RQT). According to our experiment, when our method is applied to sequences from Class A to Class E, the coding time is decreased by 44% at the cost of a 1.08% Bjontegaard delta rate (BD-rate) increase on average.

Video Image Transmissions over DDS Protocol for Unmanned Air System (DDS 표준 기반 무인기 영상 데이터 전송 연구)

  • Go, Kyung-Min;Kwon, Cheol-Hee;Lee, Jong-Soon;Kim, Young-Taek
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.35 no.11B
    • /
    • pp.1732-1737
    • /
    • 2010
  • Currently, one of the main purposes of the military using Unmanned Air System (VAS) is to perform surveillance and reconnaissance of hostile enemy. To carry out their mission, Unmanned aerial vechicle (UAV) transmits video images to ground control station using ISR devices installed on the UAV. After receiving the images, the ground control station distribute them to various type of users. At this case, it is important to keep QoS. This paper presents data delivery and QoS managements using DDS for DDS for UAV video images. The experiment result, based on H.264 and JPEG2000, shows that DDS standard is able to be applied to video image transmission for UAS.

DCT-Based Subpixel-Accuracy Motion Estimation Utilizing Shifting Matrix (Shifting Matrix를 이용한 DCT 기반 부화소 단위 움직임 예측 알고리즘)

  • Shin, Jae-Young;Ryu, Chul
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.40 no.2
    • /
    • pp.372-379
    • /
    • 2015
  • The latest video compression standard (such as H.264/AVC and HEVC) utilizes quarter-pel accuracy motion estimation in order to retain detailed motion information. Many sub-pixel motion estimation algorithms used in the spatial domain usually encounters increment of computational complexity due to embedded interpolation algorithm. In this paper, an approach to measure sub-pixel accuracy motion estimation in frequency domain using shifting matrix is proposed. Complexity can be reduced utilizing shifting matrix algorithm in frequency domain and simulation results demonstrate not only higher PSNR but lower bit rates than spatial domain algorithms.

An Efficient Mode Decision Method for Fast Intra Encoding in the SVC Enhancement Layer (SVC 향상 계층의 빠른 인트라 부호화를 위한 효율적인 모드 결정 방법)

  • Cho, Mi-Sook;Kang, Jin-Mi;Chung, Ki-Dong
    • Journal of Korea Multimedia Society
    • /
    • v.14 no.7
    • /
    • pp.872-883
    • /
    • 2011
  • SVC is an emerging video coding standard as an extension of H.264/AVC. This standard uses inter prediction, intra prediction and a new inter-layer prediction to improve coding performance of enhancement layers. However, it has high computational complexity. In this paper, we propose an efficient intra prediction mode decision method in the spatial enhancement layer to reduce the computational complexity. The proposed method consists of two phases. In the first phase, Intra_BL mode is selected using the RD cost of Intra_BL in advance. We exploit the fact that the RD cost and prediction mode are similar to those of neighbor macroblocks. In the second phase, we predict the enhancement layer mode using correlation between intra mode of enhancement layer and that of the base layer. Experimental results show that the proposed method could save from 48.15% to 56.32% in encoding time while degradation in video quality is negligible.

The Study on Antioxidant and Anti-inflammatory Effects of Taraxacum platycarpum H. Dahlstedt, Lonicera japonica Thunberg and Leonurus japonicus Houtt. Complex (포공영, 금은화, 익모초 혼합물의 항산화 및 항염증 효과에 관한 연구)

  • Sung Sin Huh;Young Il Kim
    • The Journal of Korean Medicine
    • /
    • v.44 no.3
    • /
    • pp.10-28
    • /
    • 2023
  • Objectives: This study was designed to experiment with the antioxidant and anti-inflammatory effects of Taraxacum platycarpum H. Dahlstedt, Lonicera japonica Thunberg, and Leonurus japonicus Houtt. complex (TLL) in LPS-induced RAW264.7 cell. Methods: The antioxidant activity of TLL was measured by FRAP assay, DPPH radical scavenging activity, ABTS radical scavenging activity. Total polyphenol and flavonoid contents of TLL were measured by using standard methods. The anti-inflammatory effects of TLL were measured by NO production, biomarker production (PGE2, IL-1β, IL-6, TNF-α), mRNA expression level (iNOS, COX-2, IL-1β, IL-6, TNF-α) and protein expression level (ERK, JNK, p38). Results: Total polyphenol and flavonoid contents in TLL were 58.03±1.02 mg of Gallic acid equivalents (GAE)/g and 16.58±0.60 mg of Quercetin equivalents (QE)/g respectively. In FRAP assay, DPPH and ABTS radical scavenging activity, a concentration-dependent increase in TLL was observed. To explore antioxidant and anti-inflammatory effects of TLL, RAW 264.7 cells were treated with TLL and LPS for 24 hours. Cell viability of RAW 264.7 cells were measured by adding EZ-Cytox, It was remarkably increased at 50, 100, 200 ㎍/㎖ concentrations of TLL. NO, ROS, iNOS, IL-1β, IL-6, TNF-α, ERK, JNK and p38 were remarkably decreased at 50, 100, 200 ㎍/㎖ concentrations of TLL compared to the control group. PGE2 and COX-2 were remarkably decreased at 100, 200 ㎍/㎖ concentrations Conclusion: These results suggest that TLL complex has antioxidant and anti-inflammatory effects.

A Study on the Method of Minimizing the Bit-Rate Overhead of H.264 Video when Encrypting the Region of Interest (관심영역 암호화 시 발생하는 H.264 영상의 비트레이트 오버헤드 최소화 방법 연구)

  • Son, Dongyeol;Kim, Jimin;Ji, Cheongmin;Kim, Kangseok;Kim, Kihyung;Hong, Manpyo
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.28 no.2
    • /
    • pp.311-326
    • /
    • 2018
  • This paper has experimented using News sample video with QCIF ($176{\times}144$) resolution in JM v10.2 code of H.264/AVC-MPEG. The region of interest (ROI) to be encrypted occurred the drift by unnecessarily referring to each frame continuously in accordance with the characteristics of the motion prediction and compensation of the H.264 standard. In order to mitigate the drift, the latest related research method of re-inserting encrypted I-picture into a certain period leads to an increase in the amount of additional computation that becomes the factor increasing the bit-rate overhead of the entire video. Therefore, the reference search range of the block and the frame in the ROI to be encrypted is restricted in the motion prediction and compensation for each frame, and the reference search range in the non-ROI not to be encrypted is not restricted to maintain the normal encoding efficiency. In this way, after encoding the video with restricted reference search range, this article proposes a method of RC4 bit-stream encryption for the ROI such as the face to be able to identify in order to protect personal information in the video. Also, it is compared and analyzed the experimental results after implementing the unencrypted original video, the latest related research method, and the proposed method in the condition of the same environment. In contrast to the latest related research method, the bit-rate overhead of the proposed method is 2.35% higher than that of the original video and 14.93% lower than that of the latest related method, while mitigating temporal drift through the proposed method. These improved results have verified by experiments of this study.

CHROMA FORMAT SCALABLE VIDEO CODING

  • Jia, Jie;Kim, Hae-Kwang;Choi, Hae-Chul
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2009.01a
    • /
    • pp.23-27
    • /
    • 2009
  • A scalable video coding (SVC) extension to the H.264/AVC standard has been developed by the Joint Video Team (JVT). SVC provides spatial, temporal and quality scalability with high coding efficiency and low complexity. SVC is now developing the extension of the first version including color format scalability. The paper proposes to remove some luminance related header and luminance coefficients when an enhancement layer adds only additional color information to its lower layer. Experimental results shows 0.6 dB PSNR gain on average in coding efficiency compared with an approach using the existing SVC standard.

  • PDF

A Fast Rough Mode Decision Algorithm for HEVC

  • Yao, Wei-Xin;Yang, Dan;Lu, Gui-Fu;Wang, Jun
    • Journal of Information Processing Systems
    • /
    • v.15 no.3
    • /
    • pp.492-499
    • /
    • 2019
  • HEVC is the high efficiency video coding standard, which provides better coding efficiency contrasted with the other video coding standard. But at the same time the computational complexity increases drastically. Thirty-five kinds of intra-prediction modes are defined in HEVC, while 9 kinds of intra prediction modes are defined in H.264/AVC. This paper proposes a fast rough mode decision (RMD) algorithm which adopts the smoothness of the up-reference pixels and the left-reference pixels to decrease the computational complexity. The three step search method is implemented in RMD process. The experimental results compared with HM13.0 indicate that the proposed algorithm can save 39.7% of the encoding time, while Bjontegaard delta bitrate (BDBR) is increased slightly by 1.35% and Bjontegaard delta peak signal-to-noise ratio (BDPSNR) loss is negligible.

Properties of Glued Laminated Timber Made from Fast-growing Species with Mangium Tannin and Phenol Resorcinol Formaldehyde Adhesives

  • Hendrik, Jessica;Hadi, Yusuf Sudo;Massijaya, Muh Yusram;Santoso, Adi;Pizzi, Antonio
    • Journal of the Korean Wood Science and Technology
    • /
    • v.47 no.3
    • /
    • pp.253-264
    • /
    • 2019
  • This study characterized the chemical compounds in tannin from mangium (Acacia mangium) bark extract and determined the physical-mechanical properties of glued laminated timber (glulam) made from sengon (Falcataria moluccana), jabon (Anthocephalus cadamba), and mangium wood. The adhesives used to prepare the glulam were based on mangium tannin and phenol resorcinol formaldehyde resin. Five-layer glulam beams measuring $5cm{\times}6cm{\times}120cm$ in thickness, width, and length, respectively, were made with a glue spread of $280g/m^2$ for each glue line, cold pressing at $10.5kgf/cm^2$ for 4 h and clamping for 20 h. Condensed mangium tannin consisted of 49.08% phenolic compounds with an average molecular weight of 4745. The degree of crystallinity was 14.8%. The Stiasny number was 47.22%. The density and the moisture content of the glulams differed from those of the corresponding solid woods with mangium having the lowest moisture content (9.58%) and the highest density ($0.66g/cm^3$). The modulus of rupture for all glulam beams met the JAS 234-2003 standard but the modulus of elasticity and the shear strength values did not. Glulam beams made with tannin had high delamination under dry and wet conditions, but glulam made from sengon and jabon wood met the standard's requirements. All glulam beams had low formaldehyde emissions and were classified as $F^{****}$ for formaldehyde emissions according to the JAS 234 (2003) standard.