• Journal of Broadcast Engineering
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• v.17 no.5
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• pp.725-733
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• 2012

MPEG and VCEG have constituted a collaboration team called JCT-VC(Joint Collaborative Team on Video Coding) and have been developing the HEVC(High Efficiency Video Coding) standard. The next generation video coding standard HEVC shows higher compression rate compared with the H.264/AVC standard, but the encoder computational complexity of the HEVC encoder is significantly high. In order to reduce this computational complexity in the HEVC encoder, a fast prediction unit decision is proposed. The proposed fast prediction unit decision method reduces the encoder complexity by skipping the remaining prediction units if the current prediction unit does not have any non-zero quantized transform coefficient. The proposed method reduces the encoder computational complexity by 50.3% comparing with HM6.0 but it maintains the same level of coding efficiency.

• ETRI Journal
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• v.26 no.2
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• pp.122-135
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• 2004

Although frame-based MPEG-4 video services have been successfully deployed since 2000, MPEG-4 video coding is now facing great competition in becoming a dominant player in the market. Object-based coding is one of the key functionalities of MPEG-4 video coding. Real-time object-based video encoding is also important for multimedia broadcasting for the near future. Object-based video services using MPEG-4 have not yet made a successful debut due to several reasons. One of the critical problems is the coding complexity of object-based video coding over frame-based video coding. Since a video object is described with an arbitrary shape, the bitstream contains not only motion and texture data but also shape data. This has introduced additional complexity to the decoder side as well as to the encoder side. In this paper, we have analyzed the current MPEG-4 video encoding tools and proposed efficient coding technologies that reduce the complexity of the encoder. Using the proposed coding schemes, we have obtained a 56 percent reduction in shape-coding complexity over the MPEG-4 video reference software (Microsoft version, 2000 edition).

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1383-1386
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• 1997

Discrete cosine transform(DCT) is the most popular block transform coding in lossy mode. DCT is close to statistically optimal transform-the Karhunen Loeve transform. In this paper, a module for DCT encoder is made with TMS320C80 based on JPEG and MPEG, which are intermational standards for image compression. the DCT encoder consists of three parts-a transformer, a vector quantizer and an entropy encoder.

• Aerospace Engineering and Technology
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• v.6 no.2
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• pp.157-163
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• 2007

The purpose of this study is to design and simulate Reed Solomon encoder(255,223) in PCM/FM communication system in order to transmit the KSLV-I onboard video data. Especially in the compressed video data transmission applications, the communication system is required to have a very low BER performance because of interframe or interframe compression techniques. We have used the primitive polynomial of CCSDS standard and calculated the various coefficients and then the encoder have been simulated as a part of RF interface FPGA hardware in a video compression unit.

• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.3
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• pp.63-72
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• 1999

Recent studies on the Constant Bit Rate and Variable Bit Rate transmissions have mainly focused on the frame by frame encoder rate control based on the quantization parameter. With the existing approaches it is difficult to guarantee a consistent video quality. Also, the rate control overhead is too high for the real-time video sources. In this paper, a channel rate allocation scheme based on the control period is proposed to transmit a real-time video, in which the control period is defined by a pre-specified number of frames or group of pictures. At each control period, video traffic information is collected to determine the channel rate at the next control period. The channel rate is allocated to satisfy various channel rate constraints such that the buffer occupancy at the decoder is maintained at a target level. If the allocated channel rate approaches the level at which the negotiated traffic descriptions may be violated, the encoder rate is decreased through adjusting quantization parameters in the MPEG encoder. In the experimental results, the video quality and the overflow and underflow probabilities at the buffer are compared at different control periods. Experiments show that the video quality and the utilization of network bandwidth resources can be optimized through the suitable selection of the control period.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.50-53
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• 2002

There are increasing needs to deliver the multimedia streaming over heterogeneous networks. When considering network environments and equipment accessed by user, delivery of video streaming must be scalable. There are many kinds of scalable video coding: spatial, temporal, SNR, and hybrid. The SNR scalable and spatial resolution, but different SNR quality with respect to layers. The 1-layer SNR scalable encoder produces SNR scalable video streams with ease. But, there is drift problem. Modified 1-layer approach does not have this problem but coding inefficiency, and is not MPEG-compliant. The present MPEG-compliant 2-layer encoder comes out to reduce coding rate. But it still use only base layer to encode whole layer. In this paper, we propose adaptive MPEG-compliant 2-layer encoder. Using linear combination algorithm, encoder use 1 motion vector to encode the sequences efficiently. By dong this, we can achieve the coding efficiency of SNR scalable coding.

• Journal of Broadcast Engineering
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• v.1 no.2
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• pp.152-164
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• 1996

This paper describes the hardware architecture and implementation trade-offs of the Grand Alliance HDTV video encoder system. The implemented video encoder accepts video in 1125 line(30Hz) interlaced format, and produces a bit-stream compliant with the motion picture experts group version 2(MPEG-2) standards. The encoder processing includes large- area motion estimation and an advanced rate control mechanism. To keep the system complexity realizable, we adopt a fast hierarchical motion estimation method and developed its hardware architecture. Furthermore an adaptive perceptual quantization method is adopted to improve the perceptual quality. The developed system Is based on the 4-way parallel processing architecture and is implemented by using programmable IC, memory IC, and special-purpose processors such as DCT and motion estimation processors.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11C
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• pp.1083-1090
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• 2005

This paper presents the design of a video encoder for the device of need TV-OUT function. The designed video encoder satisfies the standard conditions of International Telecommunication Union-Radiocommunication (ITU-R) BT.470. ITU-R BT.470 can be classified as NTSC, PAL or SECAM. NTSC and PAL use Amplitude Modulation (AM) to transmit color difference signals and SECAM uses Frequency Modulation (FM). SECAM must have an antic-cloche filter but the filter recommended by ITU-R BT.470 is not easy to design due to sharpness of the frequency response. So formerly the filter was designed as analog. This paper proposes that the filter is designed as digital and the special quality of the filter is transformed easy to design. And the modulation method is modified to be identical with the result required at standard. The encoder can control power consumption by output mode to apply mobile phone, mobile devices, etc. The proposed encoder is experimentally demonstrated with ALTERA FPGA APEX20KE EP20K1000EBC652-3 device and SAMSUNG LCD-TV.

• Journal of Broadcast Engineering
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• v.15 no.1
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• pp.112-121
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• 2010

Distributed video coding is a coding paradigm that allows complexity to be shared between encoder and decoder, in contrast with conventional video coding. We propose that complexity balancing method of encoder/decoder by phase motion estimation algorithm. The encoder performs partial motion estimation. The result of the partial motion estimation is transferred to the decoder, and the decoder performs motion estimation within the narrow range. When the encoder can afford some complexity, complexity balancing is possible. The method proposed is able to know relativity between complexity balancing and coding efficiency. The coding efficiency increase rate by the encoder complexity increases is higher than that by the decoder complexity increases. The proposed method can control the complexity and coding efficiency according to devices' resources and channel conditions.

• Proceedings of the IEEK Conference
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• 2003.07d
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• pp.1685-1688
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• 2003

The modem multimedia applications which are video Processor, video conference or video phone and so forth require real time processing. Because of a large amount of image data, those require high compression performance. In this paper, the proposed image processing encoder was designed by using wavelet transform encoding. The proposed filter block can process image data on tile high speed because of composing individual function blocks by parallel and compute both highpass and lowpass coefficient in the same clock cycle. When image data is decomposed into multiresolution, the proposed scheme needs external memory and controller to save intermediate results and it can operate within 33㎒.