• ETRI Journal
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• 제26권2호
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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).

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1998년도 Proceedings of International Workshop on Advanced Image Technology
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• pp.183-188
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• 1998

This paper describes the concept of object-based coding for future broadcasting environments. Digital broadcasting uses the MPEG2 coding scheme which is regarded as a picture-based coding. An object-based coding scheme is a potential candidate for future broadcasting both for studio and distribution uses, and it offers a higher compression more flexible content handling. This paper also describes key technologies that we have been developing for the object-based coding, e.g., image analysis, object extraction and coding of objects.

• 대한전자공학회논문지SP
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• 제47권5호
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• pp.45-55
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• 2010

객체 기반 오디오 부호화 기술은 다양한 응용 분야를 기대할 수 있는 차세대 오디오 기술로써 관심이 높다. 최근 MPEG에서는 SAOC (Spatial Audio Object Coding)라는 압축 효율이 우수한 Parametric 객체 부호화 방법을 표준화하였다. 본 논문에서는 SAOC를 중심으로 Parametric 객체 오디오 부호화의 기술을 소개하고, 이를 실제 적용하기 위한 고려사항들에 대해 다룬다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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• pp.53-56
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• 2000

In progressive image coding, if object region that have main contents in image are transmitted prior to the remained region, this method will be very useful. In this paper, the progressive image coding based on SPIHT using object region transmission method by priority is proposed. First, an original image is transformed by wavelet. Median filtering is used about wavelet transformed coefficient region for extracting object region. This extracted object region encoded by SPIHT. Then encoded object region are transmitted in advance of the remained region. This method is good to a conventional progressive image coding about entire original image. Experimental results show that the proposed method can be very effectively used for image coding applications such as internet retrieval and database searching system.

• ETRI Journal
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• 제33권6호
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• pp.945-948
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• 2011

Object-based audio coding can provide new music applications with interactivity. To efficiently compress a lot of target audio objects, a subband-based parametric coding scheme has been adopted for MPEG spatial audio object coding. In this letter, the time-frequency (T/F) subband analysis structure is investigated. A reconfigured T/F structure is also proposed to enhance the generating performance of sound scenes such as 'karaoke' and 'solo' play in interactive music scenarios. From the experimental results, it was confirmed that the proposed scheme remarkably improves the SNR and sound quality.

• 한국정보과학회논문지:시스템및이론
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• 제31권5_6호
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• pp.305-320
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• 2004

움직임 객체 분할은 내용 기반 응용을 위하여 핵심적인 것이다. 다중 프레임 차이 누적은 프레임 차이 정보를 누적하여 움직임 에지를 검출한다. 검출된 움직임 에지와 분할될 현재 프레임의 에지를 비교하여 움직임 객체 에지를 생성한다. 그러나 실시간 카메라로 입력되는 연속 동영상의 움직임 객체 에지에는 객체 색과 배경 색의 일치 혹은 객체의 움직임 감소로 말미암아 에지 단락이 발생한다. 에지 단락은 매우 심각한 문제로서 움직임 객체의 영상 품질을 심하게 손상시키는 경우도 있다. 본 연구에서는 강건하고 포괄적인 에지 연결 알고리즘을 개발하여 이 문제를 해결하였다. 또한 본 연구에서는 자동 움직임 객체 분할 알고리즘을 개발하여 분명하고 깨끗한 모양의 움직임 객체를 자동으로 분할하였다. 개발한 알고리즘은 CIF 영상을 초당 30 프레임 이상 처리할 수 있다. 본 논문에서 개발한 알고리즘은 MPEG-4 내용 기반 코딩 시스템에 적용할 수 있다.

• 한국통신학회논문지
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• 제24권12B호
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• pp.2349-2358
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• 1999

본 논문에서는 스테레오 동영상의 객체기반 부호화 기법을 제안하였다. 스테레오 영상열의 정보량을 줄이면서 블록화 현상이나 모스키토 현상과 같은 블록정합 기반 방법의 예측오차를 줄이기 위해서는 객체기반 부호화 기법이 필요하다. 객체기반 방법에서는 부호화에 적절한 객체를 추출하기가 어렵고, 추출된 객체에 대해서 프레임이 지남에 따라 갱신해 주어야 하는 문제점이 발생한다. 이를 개선하기 위해서 제안된 방법에서는 전처리, 객체추출, 객체갱신 과정을 사용하였다. 전처리 과정에서는 움직임과 변이 예측의 신뢰성이 낮은 영역을 비객체영역으로 분할하여 부정확한 객체의 추출을 방지하였다. 객체추출 과정에서는 좌영상의 예측을 향상시키기 위해 기존의 움직임과 밝기값을 고려하는 영상분할법에 변이를 추가함으로서 객체기반 부호화에 적합한 객체를 추출하였다. 그리고 객체갱신 과정에서는 새로운 객체의 추출, 객체분할, 객체 병합을 적용하여 누적 오차를 줄였다.

• 전자공학회논문지S
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• 제34S권5호
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• pp.45-51
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• 1997

To trnsmit moving image signals by using an object vased coding technique at the rate of 8kbps~11kbps, it is very important to minimize the bit rates used for the compression of the color information of MF-objects. This paper proposes a hybrid coding method which uses the shpae adaptive coding method and the interframe reference method selectively. Gilge's shape adaptive orthogonal coidng method is utilized for shpae adaptive coding. The interfarame reference method approximates the low-passed signals of the image by gilge's shpae adaptive orthogonalization method and then refers the approximation error signals from the high frequency signal components of th eprevious frame. The proposed method achives the bit rates reduction of 17% compared to the gilge's shape adaptive orthogonalization method and 30% rduction compared to the shape adaptive DCT in average.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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• pp.97-100
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• 2000

This paper presents a new approach to the vertex based shape coding technique. The conventional approaches encode objects using a spline method with the same distortion coefficients. The proposed approach, however, classifies the objects based on the object's features, and then applies different distortion values depending on the classified object types. Using this pre-classifying technique, this paper reduces the bit rate and the computational complexity necessary for the encoding process. The performance of the proposed method has been proved by experiments on the various sample Images.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.294-297
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• 2009

Multi-view video consists of a set of multiple video sequences from multiple viewpoints or view directions in the same scene. It contains extremely a large amount of data and some extra information to be stored or transmitted to the user. This paper presents inter-view correlations among video objects and the background to reduce the prediction complexity while achieving a high coding efficiency in multi-view video coding. Our proposed algorism is based on object-based segmentation scheme that utilizes video object information obtained from the coded base view. This set of data help us to predict disparity vectors and motion vectors in enhancement views by employing object registration, which leads to high compression and low-complexity coding scheme for enhancement views. An experimental results show that the superiority can provide an improvement of PSNR gain 2.5.3 dB compared to the simulcast.