• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.103-107
• /
• 2013

In this paper, A real-time lane tracking algorithm is proposed for lane departure warning system. To eliminate perspective effect, input image is converted into Bird's View by inverse perspective mapping. Next, suitable features are extracted for lane detection. Lane feature that correspond to area of interest and RANSAC are used to detect lane candidates. And driving lane is decided by clustering of lane candidates. Finally, detected lane is tracked using the Kalman filter. Experimental results show that the proposed algorithm can be processed within 30ms and its detection rate is approximately 90% on the highway in a variety of environments such as day and night.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.40 no.1
• /
• pp.45-51
• /
• 2003

JPEG200, a new international standard for still image compression based on wavelet and bit-plane coding techniques, is developed. In this paper, we design the DWT(Discrete Wavelet Transform) and quantizer for JPEG2000 CODEC. DWT handles both lossy and lossless compression using the same transform-based framework: The Daubechies 9/7 and 5/3 transforms, and quantizer is implemented as SQ(Scalar Quantization). The architecture of the proposed DWT and SQ are synthesized and verified using Xilinx FPGA technology. It operates up to 30MHz, and executes algorithms of wavelet transform and quantization for VGA 10 frame per second.

• Proceedings of the Korean Information Science Society Conference
• /
• 2005.07a
• /
• pp.271-273
• /
• 2005

많은 글로벌 기업들이 비용절감 및 효율성 증대를 위하여 RFID 시스템을 도입하거나 도입을 적극 검토 중에 있다. RFID 시스템으로부터 획득된 수많은 정보들이 기업의 업무효율을 증대시킬 수 있도록 하기 위해서는 상위 응용 서비스에서 RFID 데이터를 효율적으로 사용할 수 있도록 리더와 응용 서비스 간의 중계 역할을 할 수 있는 RFID 미들웨어의 역할이 매우 중요하다. 이러한 요구사항에 맞춰 최근 EPCglobal에서는 RFID 미들웨어인 ALE(Application Level Event)를 제시하고 있다. ALE는 RFID 리더에 의해 읽혀진 EPC 이벤트 데이터를 실시간으로 수집하여 원본 데이터의 오류를 보정한 후에 사용자와 응용 서비스의 요구에 따라 특정 이벤트 데이터를 필터링하여 보고하는 역할을 한다. 본 논문에서는 ALE의 실시간 EPC 이벤트 데이터 처리를 위한 EMS(Event Management System) 컴포넌트를 제시하며 EMS에 대한 요구사항을 분석하고 설계하였다. EMS 컴포넌트는 RFID 리더를 통해서 끊임없이 들어오는 스트링 형태의 EPC 이벤트 데이터를 블록킹 없이 수집하는 역할을 한다. 또한, RFID 리더에서 수집한 데이터의 보정 및 필요 데이터 추출을 위한 다양한 필터링 기능을 제공함으로써 수집된 데이터의 정확성을 높이며 신속한 데이터 제공을 가능하게 한다.

• Journal of Broadcast Engineering
• /
• v.24 no.3
• /
• pp.485-494
• /
• 2019

A software-driven real-time frequency de-modulator is implemented with the aid of universal-serial-bus (USB) type software defined radio dongle. An analog stereo frequency modulation (FM) broadcast signal is down-converted to the basedband analog signal then converted to digital bit streams in the USB dongle. Computer software such as Matlab, Python, and GNU Radio manipulates the incoming bit streams with the technique of digital signal processing. Low pass filtering, band pass filtering, decimation, frequency discriminator, double sideband amplitude demodulation, phase locked loop, and deemphasis function blocks are implemented using such computer languages. Especially, GNU Radion is employed to realize the real-time demodulator.

• The Journal of the Acoustical Society of Korea
• /
• v.26 no.3
• /
• pp.129-135
• /
• 2007

In this paper. we propose a prewhitening method for the km reverberation to enhance the target signal. The proposed algorithm uses the dechirping method which inversely compensates the frequency chirp rate of LFM and transforms the LFM reverberation to have stationary frequency property in each data block. Also, using the left and right adjacent beam signals as reference signals. we model frequency response of each data block by AR coefficients. From these coefficients, we implement inverse filter and prewhiten the LFM reverberation of the center beam efficiently.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2007.05a
• /
• pp.667-670
• /
• 2007

볼륨 데이터에 대한 압축 기법의 필요성은 데이터 용량의 증가와 네트워크 사용량의 증가와 함께 더불어 증가해 왔다. 현재에는 다양한 압축 기법이 개발돼 있으며, 사용자는 데이터 유형이나 응용 분야에 맞춰 압축 기법을 선택, 적용할 수 있다. 그러나 최근에는 응용 과학자들로부터 생성되는 데이터의 용량이 기하급수적으로 증가했는데, 이렇게 응용과학 분야에서 생성되는 데이터는 대부분 3차원 볼륨 데이터다. 2차원 이미지나 3차원 동영상 데이터의 경우에는 다양한 표준 압축 방식을 사용할 수 있지만 3차원 볼륨 데이터에 적용할 수 있는 방법은 한정돼 있으며, 특히 시간가변(time-varying) 볼륨 데이터에 대한 압축 표준은 거의 존재하지 않는다고 볼 수 있다. 본 논문에서는 시간가변 볼륨 데이터에 대한 압축 방식을 제안한다. 이 방식은 가시화를 목적으로 하는 시간가변 볼륨 데이터의 인코딩을 목적으로 하며, MPEG의 I-프레임과 P-프레임 개념을 사용해서 압축률을 높인다. 본 방식은 시간가변 부동 소수점 데이터(single precision floating-point data)로 구성된 시간가변 볼륨 데이터를 대상으로 하는데, 한 블록 단위의 무작위 복원을 지원하며 Daubechies 웨이블릿 필터와 프레임간의 상관 관계를 사용, 대형 시간가변 볼륨 데이터를 이미지 화질을 보존한다.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.44 no.5
• /
• pp.45-53
• /
• 2007

To recover transmitted signal perfectly at DTV receiver, we have to acquire carrier frequency synchronization to compensate pilot signal which located in wrong position and rotated phase. Also, we need a symbol timing synchronization to compensate sampling timing error. Conventionally, to synchronize symbol timing, we use Gardner's scheme which used in multi-level signal. Gardner's scheme is well known for its sampling the timing error signal from every symbol and it makes easy to detect and keep timing sync in multi-path channel. In this paper, to discuss the problem when the received power level is out of range and we cannot get synchronization information. With this problem, we use 2 step procedures. First, we put a received signal power compensation block before Garder's timing error detector. Second, adaptive loop filter to get a fast synchronization information and averaging loop filter's output value to reduce the amount of jitter after synchronization in PLL(Phased Locked Loop) circuit which is used to get a carrier frequency synchronization and symbol timing synchronization. Using the averaging value, we can estimate offset. Based on offset changing ratio, we can adapt adaptive loop filter to carrier frequency and symbol timing synchronization circuit.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.2
• /
• pp.391-396
• /
• 2013

In this paper, for HEVC decoding, an SAO hardware design with less processing time and reduced area is proposed. The proposed SAO hardware architecture introduces the design processing $8{\times}8$ CU to reduce the hardware area and uses internal registers to support $64{\times}64$ CU processing. Instead of previous top-down block partitioning, it uses bottom-up block partitioning to minimize the amount of calculation and processing time. As a result of synthesizing the proposed architecture with TSMC $0.18{\mu}m$ library, the gate area is 30.7k and the maximum frequency is 250MHz. The proposed SAO hardware architecture can process the decode of a macroblock in 64 cycles.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.35S no.8
• /
• pp.106-112
• /
• 1998

Recently, the amount of image and audio data has been increasing dramatically for high performance. According to this trend, a high-density magnetic recording system is necessitated and the tracks of magnetic tapes are getting narrower. This, in turn, requires the capstan servo system of the magnetic recording system such as DVCR to control precisely the speed and position of the capstan motor. Especially, in case of play-back, the capstan servo system should be able to position and maintain the head on the desired place of the track. To meet this requirement, digital camcorders use ATF (Automatic Track Following). In this paper, a new ATF block using discrete Fourier transform is proposed. The proposed ATF block was designed and implemented in ALTERA FPGA chips and fully tested in a real DVCR system. It is shown through experiments that the new ATF block is more cost-effective than other existing ATF blocks using digital lowpass filters. In particular, the number of logic gates can be reduced by 20% in average, compared to the existing ATF's.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.8C
• /
• pp.790-800
• /
• 2009

For the improvement of coding efficiency, the H.264/AYC standard uses new coding tools such as 1/4-pel-accurate motion estimation, multiple references, intra prediction, loop filter, variable block size etc. Using these coding tools, H.264/AYC has achieved significant improvements from rate-distortion point of view compared to existing standards. However, the encoder complexity was greatly increased due to these coding tools. We focus on the complexity reduction method of intra macroblock mode selection. The proposed algorithm for fast intra mode selection calculates the edge activity in transform domain, and performs fast encoding of intra frame in H.264/AYC through the fast prediction mode selection of intra4x4 and chrominance blocks. Simulation results show that the proposed method saves about 59.76% for QCIF sequences and 65.03% for CIF sequences of total encoding time, while bitrate increase and PSNR decrease are very small.