• Journal of Korea Society of Digital Industry and Information Management
• /
• v.16 no.2
• /
• pp.27-33
• /
• 2020

Backward compatibility is one of the key issues for radio equipment supporting IEEE 802.11, the typical wireless local area networks (WLANs) communication protocol. For a successful packet decoding with the backward compatibility, the frame format detection is a core precondition. This paper presents a novel frame format detection method based on a deep learning procedure for WLANs affiliated with IEEE 802.11. Considering that the detection performance of conventional methods is degraded mainly due to the poor performances in the symbol synchronization and/or channel estimation in low signal-to-noise-ratio environments, we propose a novel detection method based on convolutional neural network (CNN) that replaces the entire conventional detection procedures. The proposed deep learning network provides a robust detection directly from the receive data. Through extensive computer simulations performed in the multipath fading channel environments (modeled by Project IEEE 802.11 Task Group ac), the proposed method exhibits superb improvement in the frame format detection compared to the conventional method.

• Proceedings of the IEEK Conference
• /
• 2003.07e
• /
• pp.2040-2043
• /
• 2003

General-purpose MPEG-2 video transcoders must be able to achieve any conversion between 18 ATSC (Advanced television system committee) video formats for DTV (digital television), e.g., scan format, size format, and frame rate format conversion. Especially, scan format conversion is hard to implement because frame rate and size format conversion often happen together. This paper proposes a fast motion estimation(ME) algorithm for MPEG-2 video transcoding supporting scan format conversion. Firstly, we extract and compose a set of candidate motion vectors (MV's) from the input bit-stream to comply with the re-encoding format. Secondly, the best MV is chosen among several candidate MV's by using a weighted median selector. Simulation results show that the proposed ME algorithm reduces significantly transcoding complexity with a minor PSNR degradation.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.1
• /
• pp.175-181
• /
• 1999

There are issues regarding how some of traffic parameters should be set so that ATM and non-ATM service parameters can be compatible. For example, policing method used by frame relay based on CIR(committed information rate) will not exactly match the ATM UPC(Usage Parameter Control) method. ATM and the frame relay have different transfer modes and traffic parameters. The cells and frames are police by their own traffic control schemes. For the same information, the real traffic of the ATM side takes greater bandwidth than that of the frame relay side caused by ATM cell format and AAL5 format. IN both networks this bandwidth than that of the frame relay side caused by ATM cell format and AAL5 format. In both networks this bandwidth ratio should be considered on traffic parameter mapping to maintain their QoS and to perform efficient network resource management. In this paper we describe traffic parameter mapping schemes between frame relay and ATM in ATM network and how to expect the bandwidth ratio to maintain FR QoS in ATM network. We assumed frame length distribution to Erlang or Exponential probability density function.

• Proceedings of the Korea Institute of Convergence Signal Processing
• /
• 2000.12a
• /
• pp.37-40
• /
• 2000

This paper deal with a movable boundary multiple access scheme and frame format for ATM over satellite. By mathematical modeling and simulation, we can see that suggested frame format is suitable for non-realtime traffic users.

• Journal of Broadcast Engineering
• /
• v.8 no.3
• /
• pp.288-296
• /
• 2003

ATSC (Advanced Television System Committee) has specified 18 video formats for DTV (Digital Television), e.g., scan format, size format, and frame rate format conversion. Effective MPEG-2 video transcoders should support any conversion between the above-mentioned formats. Scan format conversion Is hard to Implement because it may often induce frame rate and size format conversion together. Especially. because of picture type conversion caused by scan format conversion, the computational burden of motion estimation (ME) in transcoding becomes serious. This paper proposes a fast ME algorithm for MPEG-2 video transcoding supporting scan format conversion. Firstly, we extract and compose a set of candidate motion vectors (MVs) from the input bit-stream to comply with the re-encoding format. Secondly, the best MV is chosen among several candidate MVs by using a weighted median selector. Simulation results show that the proposed ME algorithm provides outstanding PSNR performance close to full search ME, while reducing the transcoding complexity significantly.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.48 no.6
• /
• pp.61-67
• /
• 2011

Stereoscopic 3D video can be transmitted by frame-compatible packing format to fulfill the compatibility requirement with the existing digital TV. Then, the reduced stereo image needs to be expanded to the original size at the receiver. This paper proposes an adaptive interpolation method for the discarded image lines. The horizontal line-based linear filter and NEDI6 filter are used selectively for the interpolation of each pixel. Experimental results show that the NEDI6 combined with the horizontal line-based linear filter yields better image quality than the bilinear method by around 0.6dB.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.10c
• /
• pp.361-363
• /
• 2004

WMV(Winoow Media Video)는 ASF(Advanced Streaming Format)파일 포맷을 기반으로 하는 마이크로 소프트사의 대표적인 스트리밍 파일 포맷이다. WMV 파일 포맷은 MPEG-4를 기반으로 내용 기반 부호화를 통해 영상을 객체 단위로 나누어 처리하므로 사용자의 의도에 따라 다양한 조작과 디스플레이가 가능하다. 또한 영상 데이터를 패킷에 붙여 네트워크를 통해 스트리밍 서비스도 가능하다. 따라서 본 논문에서는 WMV파일 포맷 분석을 통해 영상의 가장 중요한 Hey-Frame을 추출과 데이터 헤더 부분을 제외한 실제 영상 스트림의 시작 위치를 찾는 알고리즘을 설계 및 구현하였다. 이로써 실제 스트리ald 서비스외에도 다양한 멀티디미어 서비스에 적용 가능한 방법을 마련하였다.

• The KIPS Transactions:PartB
• /
• v.9B no.6
• /
• pp.745-752
• /
• 2002

The purpose of the paper is to enable a format transcoding between a heterogeneous compression format in a real time, and to enhance the compression ratio using characteristics of the compressed frame. In this paper, for the heterogeneous format transcoding, we tried to transcode from MPEG2 having a lower compression ratio to H.263 having a higher compression ratio. After analyzing MPEG 2 bit stream and H.263 bit stream of the same original video, we found that the number of intra coded macro blocks in MPEG 2 data is much higher than the number of the intra coded macro blocks in H.263 data. In the process of P frame generation, a intra coded macro block is generated when a motion estimation value representing the similarity between the previous frame and current frame does not meet a threshold. Especially the intra coded macro block has a great impact on the compression ratio. Hence the paper, we tried to minimize the number of intra coded macro blocks in H.263 data stream which is transcoded from MPEG 2 in a compressed domain. For the purpose, we propose a guided search method for transcoding the INTRA coded block into INTER coded block using the information about motion vectors surrounding the intra macro block in order to minimize the complexity of the motion estimation process. The experimental results show that the transcoding of MPEG 2 into H.263 can be done in a real time successfully.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2017.11a
• /
• pp.24-27
• /
• 2017

본 논문에서는 빔-호핑 위성 전송 기반의 DVB-S2x 슈퍼프레임 수신기를 위한 프레임 검출 기법을 제안한다. 제안하는 검출 기법은 2 체배 오버샘플링 레이트에서(over-sampling rate)에서 동작을 수행하며, 슈퍼프레임의 헤더를 구성하는 start of super-frame (SOSF)과 super frame format indicator (SFFI)를 모두 이용하여 하드웨어 복잡도를 줄이면서도 견고하게 프레임을 검출할 수 있다.

• Journal of Digital Convergence
• /
• v.14 no.1
• /
• pp.189-194
• /
• 2016

Recently, there is increasing demand for image processing technology while activated the use of equipments such as camera, camcorder and CCTV. In particular, research and development related to 3D image technology using the depth camera such as Kinect sensor has been more activated. Kinect sensor is a high-performance camera that can acquire a 3D human skeleton structure via a RGB, skeleton and depth image in real-time frame-by-frame. In this paper, we develop a system. This system captures the motion of a 3D human skeleton structure using the Kinect sensor. And this system can be stored by selecting the motion file format as trc and bvh that is used for general purposes. The system also has a function that converts TRC motion captured format file into BVH format. Finally, this paper confirms visually through the motion capture data viewer that motion data captured using the Kinect sensor is captured correctly.