• 대한의용생체공학회:의공학회지
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• 제15권4호
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• pp.475-480
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• 1994

For the effective management of medical images, it becomes popular to use computing machines in medical practice, namely PACS. However, the amount of image data is so large that there is a lack of storage space. We usually use data compression techniques to save storage, but the process speed of machines is not fast enough to meet surgical requirement. So a special hardware system processing medical images faster is more important than ever. To meet the demand for high speed image processing, especially image compression and decompression, we designed and implemented the medical image CODEC (COder/DECoder) based on MISD (Multiple Instruction Single Data stream) architecture to adopt parallelism in it. Considering not being a standard scheme of medical image compression/decompression, the CODEC is designed programable and general. In this paper, we use JPEG (Joint Photographic Experts Group) algorithm to process images and evalutate the CODEC.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권10호
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• pp.446-451
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• 2006

In this paper, we propose an implementation of JPEG2000 codec on the ARM9 Processor which includes independent memory management facility. The codec and memory management facility together can control the encoding and the decoding process effectively within available memory area. Embedded appliances like cellular phones have very limited internal memory which can't be expanded easily. However, they should provide various applications and services using restricted memory resources. The proposed codec with memory management can provide image quality that is identical to the original image on embedded platform. The implemented codec has no memory conflict with other applications. It shows that the proposed codec can manage memory resources efficiently.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.797-798
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• 2006

In this paper, a codec design method is pro-posed for the face images based on JPEG and its application to face recognition is presented. Quantization table design is dis-cussed using R-D optimization for Yale face data. For the usage in the embedded systems, fast codec design is also considered. The proposed codec has better performance than JPEG codec for face images. Through the recognition experiment using PCA and LDA, it has been shown that the proposed codec has better performance than JPEG codec.

• IEIE Transactions on Smart Processing and Computing
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• 제4권6호
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• pp.434-442
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• 2015

In this paper, we propose an integrated spatial and view scalable video codec based on high efficiency video coding (HEVC). The proposed video codec is developed based on similarity and uniqueness between the scalable extension and 3D multi-view extension of HEVC. To improve compression efficiency using the proposed scalable multi-view video codec, inter-layer and inter-view predictions are jointly employed by using high-level syntaxes that are defined to identify view and layer information. For the inter-view and inter-layer predictions, a decoded picture buffer (DPB) management algorithm is also proposed. The inter-view and inter-layer motion predictions are integrated into a consolidated prediction by harmonizing with the temporal motion prediction of HEVC. We found that the proposed scalable multi-view codec achieves bitrate reduction of 36.1%, 31.6% and 15.8% on the top of ${\times}2$, ${\times}1.5$ parallel scalable codec and parallel multi-view codec, respectively.

• 한국통신학회논문지
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• 제33권8C호
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• pp.575-582
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• 2008

본 논문에서는 ITU-T의 SG15에서 채택된 G.729.1 광대역 음성 코덱을 ARM926EJ-S(R) 프로세서 코어에 적용하기 위해 기본연산자 및 산술기능 함수를 포함한 G.729.1 코덱 프로그램 일부를 어셈블리어로 변환하여 실시간으로 동작하도록 구현한 절차 및 결과를 기술하였다. G.729.1은 $8{\sim}32kbps$의 가변 전송률을 갖는 ITU-T 표준 광대역 음성 코덱이며, 입력신호는 8kHz 또는 16 kHz로 샘플링 되어 샘플 당 16 비트로 양자화된 PCM 신호를 입력받는다. 이 코덱은 앞서 표준화된 G.729 및 0.729A와 상호 호환이 가능하며 음질 향상을 위해 기존의 협대역($300{\sim}3,400Hz$)에 비해 대역폭을 광대역($50{\sim}7,000Hz$)으로 확장한 버전이다. 실시간으로 구현된 G.729.1 광대역 음성 코덱은 32kbps에서 인코더와 디코더 부분이 각각 약 31.2 MCPS 및 22.8 MCPS의 복잡도를 가지며, 실제 임베디드 시스템에서의 실행 시간은 인코더와 디코더 평균 6.75ms와 4.76ms로 총 11.5ms가 걸렸다. 또한 이 코덱은 ITU-T에서 제공하는 모든 테스트 벡터에 대해 비트 단위로 정확하게 시험하여 통과하였으며, 실제 인터넷 전화기에 적용한 실시간 음성통화에서 정상적으로 동작하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.168-171
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• 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.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2020년도 하계학술대회
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• pp.510-512
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• 2020

In this paper, we reviewed the method on the codec-agnostic design of MPEG V-PCC. The codec-agnostic approach designed V-PCC can use any video codec for compression. Thus, adoption with other codecs beside HEVC has not been systematically discussed. Through the analysis of the design issues that related to MPEG EVC and JPEG. We provided a strategy on choosing and targeting different video codecs for V-PCC.

• 전자공학회지
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• 제12권4호
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• pp.32-37
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• 1985

• 한국음향학회지
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• 제21권1호
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• pp.5-10
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• 2002

본 논문에서는 7 kHz 대역폭을 가지는 새로운 16 kbps 광대역 음성 압축기를 제안한다. 제안하는 압축기는 QMF (Quadrature Mirror Filter)를 사용하여 입력 신호를 하위 밴드와 상위 밴드로 분리하고, 하위 밴드는 AMR (Adaptive Multi Rate)음성 압축기를 이용하여 압축하고 상위밴드는 G.722.1 광대역 음성 압축기를 기반으로 새로운 압축기를 개발하여 압축한다. 특히 입력신호의 성질에 따라 상위 밴드와 하위 밴드에 할당되는 비트수를 다르게 함으로써 고정적으로 비트를 할당하는 음성 압축기보다 향상된 압축 성능을 제공하고, 웨이블릿 변환을 이용하여 상위 밴드 신호의 압축 성능을 향상시켰다. 주관적 방법으로 제안된 음성 압축기의 성능을 측정하였으며, 다양한 입력신호에 대하여 제안한 16 kbps음성 압축기가 G.722 48 kbps SB-ADPCH보다 우수한 성능을 가지는 것을 할인하였다.

• 한국통신학회:학술대회논문집
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• 한국통신학회 1982년도 추계학술발표회논문집
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• pp.33-36
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• 1982

Parameters of the design on the video codec have been studied using optical fiber transmission technology. And according to the parameters a composite DPCM codec has been designed, which is transmitting an NTSC color TV signal at a 44.736 Mbps. The results of the experiment on the codec will be useful for a better one in the next year