• Journal of Broadcast Engineering
• /
• v.10 no.3
• /
• pp.392-400
• /
• 2005

Highly integrated MPEG-4@SP video compression engine, VideoCore, is proposed for mobile application. The primary components of video compression require the high memory bandwidth since they access the external memory frequently. They include motion estimation, motion compensation, quantization, discrete cosine transform, variable length coding, and so on. The motion estimation processor adopted in VideoCore utilizes the small-size local memories such that the video compression system accesses external memory as less frequently as possible. The entire video compression system is divided into two distinct sub-systems: the integer-unit motion estimation part and the others, and both operate concurrently in a pipelined architecture. Thus the VideoCore enables the real-time high-quality video compression with a relatively low operation frequency.

• ETRI Journal
• /
• v.22 no.1
• /
• pp.20-29
• /
• 2000

In this paper, we present a design of video and audio single chip encoder/decoder for portable multimedia application. The single-chip called as video audio signal processor (VASP) consists of a video signal processing block and an audio single processing block. This chip has mixed hardware/software architecture to combine performance and flexibility. We designed the chip by partitioning between video and audio block. The video signal processing block was designed to implement hardware solution of pixel input/output, full pixel motion estimation, half pixel motion estimation, discrete cosine transform, quantization, run length coding, host interface, and 16 bits RISC type internal controller. The audio signal processing block is implemented with software solution using a 16 bits fixed point DSP. This chip contains 142,300 gates, 22 Kbits FIFO, 107 kbits SRAM, and 556 kbits ROM, and the chip size is $9.02mm{\times}9.06mm$ which is fabricated using 0.5 micron 3-layer metal CMOS technology.

• Proceedings of the KIEE Conference
• /
• 1988.07a
• /
• pp.168-171
• /
• 1988

This paper describes CODEC based on hybrid interframe and BTVQ including CRC(Conditional Replenishment Coding) system and RLC(Run Length Coding) method. Based upon the algorithm described in this paper, a practical CODEC has been designed for video conference and video phone use at 54Kbps using an ADSP-2100 as a CPU.

• Proceedings of the KIEE Conference
• /
• 1988.07a
• /
• pp.225-228
• /
• 1988

A new transmission scheme is presented for transmitting motion video at very low data rates. In this scheme, two-level cartoons are extracted from gray-level images, and their interframe differences are coded using 2D run-length coding. Experimental results show that the proposed scheme yields compression ratio as high as 216:1.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.9 no.7
• /
• pp.1485-1490
• /
• 2005

Variable length code is an integral component of many international standards on image and video compression currently. Context-based Adaptive Variable Length Coding(CAVLC) is adopted by the emerging JVT(also called H.264, and AVC in MPEG-4). In this paper, we design an architecture for CAVLC encoder, including a coeff_token encoder, level encoder, total_zeros encoder and run_before encoder. The designed CAVLC encoder can encode one syntax element in one clock cycle. As a result of implementation by Vertex-1000e of Xilinx, its operation frequency is 68MHz. Therefore, it is very suitable for video applications that require high throughput.

• Journal of Broadcast Engineering
• /
• v.14 no.3
• /
• pp.299-310
• /
• 2009

In this paper, we proposed a new method to correct the zoom lens distortion for the video sequence captured by the zoom lens. First, we defined the nonlinear zoom lens distortion model which is represented by the focal length and the lens distortion using the characteristic that lens distortion parameters are nonlinearly and monotonically changed while the focal length is increased. Then, we chose some sample images from the video sequence and estimated a focal length and a lens distortion parameter for each sample image. Using these estimated parameters, we were able to optimize the zoom lens distortion model. Once the zoom lens distortion model was obtained, lens distortion parameters of other images were able to be computed as their focal lengths were input. The proposed method has been made experiments with many real images and videos. As a result, accurate distortion parameters were estimated from the zoom lens distortion model and distorted images were well corrected without any visual artifacts.

• ETRI Journal
• /
• v.25 no.6
• /
• pp.489-502
• /
• 2003

This paper presents an MPEG-4 video codec, called MoVa, for video coding applications that adopts 3G-324M. We designed MoVa to be optimal by embedding a cost-effective ARM7TDMI core and partitioning it into hardwired blocks and firmware blocks to provide a reasonable tradeoff between computational requirements, power consumption, and programmability. Typical hardwired blocks are motion estimation and motion compensation, discrete cosine transform and quantization, and variable length coding and decoding, while intra refresh, rate control, error resilience, error concealment, etc. are implemented by software. MoVa has a pipeline structure and its operation is performed in four stages at encoding and in three stages at decoding. It meets the requirements of MPEG-4 SP@L2 and can perform either 30 frames/s (fps) of QCIF or SQCIF, or 7.5 fps (in codec mode) to 15 fps (in encode/decode mode) of CIF at a maximum clock rate of 27 MHz for 128 kbps or 144 kbps. MoVa can be applied to many video systems requiring a high bit rate and various video formats, such as videophone, videoconferencing, surveillance, news, and entertainment.

• Journal of Korean Academy of Nursing
• /
• v.28 no.2
• /
• pp.280-290
• /
• 1998

The two objectives of this study were 1) to develop an educational program based on the Self-Efficacy Theory(SET) of Bandura, and 2) to investigate the effects of the educational program on the management of menopause. The investigation process of this study was done in two phases. The first phase was to development an educational program through video tape. A telephone coaching program served as a follow-up to the educational video program and provided encouragement and support to the subjects. The second phase was the experimental stage. This experimentation was conducted to determine whether an educational program based on theory of Bandura would increase self-efficacy and management of menopause. Results : The developed video consisted of 2 parts. Part one discussed symtoms and management of menopause. Part two reflected the vicarious step-by-step success of middle-aged women's of menopause through the effective use of the 5 factors mentioned above. Telephone coaching program served as a followed to the educational video program and provided encouragement and support to the subjects. Total length of video is 32 minutes. Hypothesis stated in phase two were supported by the following result. Experimental group increased general-self-efficacy scores. Experimental group increased concrete-self-efficacy scores. Experimental group increased objective and subjective management of menopause scale.

• Journal of Communications and Networks
• /
• v.6 no.3
• /
• pp.280-286
• /
• 2004

The widespread use of the Internet and the maturing of digital video technology have led to an increase in various streaming media application. However, new classes of hosts such as mobile devices are gaining popularity, while the transmission became more heterogeneous. Due to the characteristics of mobile networks such as low speed, high error bit rate, etc., the applications over the wireless channel have different needs and limitations from desktop computers. An intermediary between two communicating endpoints to hide the heterogeneous network links is thought as one of the best approaches. In this paper, we adopted the concept of inter-packet gap and the sequence number between continuously received packets as the error discriminator, and designed an adaptive packet sizing mechanism to improve the network efficiency under varying channel conditions. Based on the proposed mechanism, the packetization scheme with error protection is proposed to scalable encoded video delivery. Finally, simulation results reveal that our proposed mechanism can react to the varying BER conditions with better network efficiency and gain the obvious improvement to video quality for stored MPEG-4 FGS video delivery.

• Korean Journal of Applied Biomechanics
• /
• v.20 no.4
• /
• pp.421-427
• /
• 2010

The purpose of this study was to investigate the relationship between the quantitative analysis of biomechanical movement and the qualitative analysis of video software in order to evaluate for the walking movement. The fourteen collegiate students who agreed with the purpose and method of this study participated as subjects. The slow walking and fast walking of the subjects in the place of experiment were photographed, and calculated several mechanical factors. This empirical evidence from the experiment indicated the significant difference(p<.001) between each distant factors of the walking movement for both analyses methods, but there was no statistically significant difference between the spacial factors observed in the experiment. For more detail, no significant difference between the walking ratios that expressed the coordination between stride length and stride frequency was found. The findings also indicated the high coefficient of correlation(over r=.9) which supports higher explanation force for the biomechanical method and the Dartfish video software method. Therefore, if the data was gathered by using the proper experimental method, the video software method could be used just like the quantitative data of biomechanical method.