• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.301-304
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• 2002

This paper describes the design and implementation results of JPEG core, based on the ITU-T Recommendation T.81. We designed the RTL circuit in Verilog HDL, making reference to the JPEG program from the Independent JPEG Group. The circuit has been simulated with Verilog-XL, synthesized with Design Compiler and verified using Altera FPGA. Since the synthesized circuit includes a small number of gates, it is expected to be used as a core module in image processing SOC.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.2267-2270
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• 2003

This paper has been studied to implement MQ encoder in JPEG2000 on FPGA. In the JPEG2000 architecture, Each of coding passes collects contextual information about the bit-plane data. An MQ coder uses contextual information and its internal state to decode a compressed bit-stream. This paper draws up JPEG2000 Standard Part 1: FCD 15444-1 It is simulated with Modelsim and tested with JBIG2 data.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.05b
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• pp.724-727
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• 2003

현재 웹상의 이미지 갤러리에는 이미지와 함께 제목이나 설명이 포함되는 경우가 많다. 본 논문에서는 갤러리의 검색, 정렬 등의 기능을 강화하고 이미지와 정보의 통합을 위해서 JPEG 이미지의 헤더를 확장하여 이미지의 저작자, 만든 날짜, 설명, 파일크기 등의 텍스트 정보를 내장한 Text Embedded JPEG를 고안하였다. 이 Text Embedded JPEG를 이용한 웹 갤러리에서 이용자는 이미지에 대한 보다 자세한 정보를 볼 수 있고 이 각각의 정보들에 따라 정렬할 수도 있고 이미지 정보를 변경할 수도 있도록 설계하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04b
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• pp.435-437
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• 2000

본 논문은 IJG JPEG 시스템에서 사용된 효율적인 메모리 관리 방법에 대해 소개한다. IJG JPEG 시스템의 메모리 관리 모듈은 여러 시스템에 독립적일 수 있도록 다양한 종류의 메모리 관리 모듈을 두고 있다. 각 메모리 관리 모듈은 메모리 객체를 small, large, virtual의 3가지로 구분하여 할당/해제하는데, 객체 단위로 할당/해제하지 않고

• Proceedings of the KSRS Conference
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• v.1
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• pp.282-285
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• 2006

This paper analyzed the characteristics of the Lossy JPEG of the meteorological satellite image, and analyzed the quality of the Lossy JPEG compression, which is proper for the LRIT(Low Rate Information Transmission) to be serviced to the SDUS(Small-scale Data Utilization Station) system of the COMS(Communication, Oceans, Meteorological Satellite). Since COMS is to start running after 2008, we collected the data of the MTSAT-1R(Multi-functional Transport Satellite -1R) for analysis, and after forming the original image to be used to LRIT by each channel and time zone of the satellite image data, we set the different quality with the Lossy JPEG compression, and compressed the original data. For the characteristic analysis of the Lossy JPEG, we measured PSNR(Peak Signal to Noise Rate), compression rate and the time spent in compression following each quality of Lossy JPEG compression. As a result of the analysis of the satellite image data of the MTSAT-1R, the ideal quality of the Lossy JPEG compression was found to be 90% in the VIS Channel, 85% in the IR1 Channel, 80% in the IR2 Channel, 90% in the IR3 Channel and 90% in the IR4 Channel.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.425-428
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• 2005

This paper is made up Advanced Image Coding(AIC) that combines algorithms from next generation image coding standard, H.264/MPEG-4 Part 10 advanced video coding(AVC) and still image compression standard, JPEG(Joint Photographic Experts Group). AIC combines intra frame block prediction from H.264 with a JPEG style discrete cosine transform and quantization, followed by Context-based Adaptive Binary Arithmetic Coding(CABAC) as used in H.264. In this paper, we analyzes the efficiency of the AIC algorithm and JPEG and JPEG-2000, and it presents of result.

• The KIPS Transactions:PartA
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• v.13A no.3 s.100
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• pp.185-190
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• 2006

JPEG 2000 is used as an alternative to solve the blocking artifact problem with the existing still image compression JPEG algorithm. However, it has shortcomings such as longer floating point computation time and more complexity in the procedure of enhancing the image compression rate and decompression rate. To compensate for these we implemented with hardware the JPEG 2000 algorithm's filter part which requires a lot of floating point computation. This DWT Filter[1] chip is designed on the basis of Daubechies 9/7 filter[6] and is composed of 3-stage pipeline system to optimize the performance and chip size. Our implemented Filter was 7 times faster than software based Filter in the floating point computation.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.2
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• pp.359-367
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• 2016

As taking pictures by using smartphones has become more common in society, there are many incidents which are unexpected manipulation of images and leak of confidential information. Because of those incidents, demands that identify forgery/alteration of image file and proves of the original copy is constantly increasing. In general, smartphone saves image file as JPEG form and it has DQT which determines a compression rate of image in a header part of image. There is also DQT in Thumbnail image which inside of JPEG. In previous research, it identified a smartphone which take image by only using DQT, However, the research has low accuracy to identify the devices. There are two main purposes in this research. First, this research will analogize a smartphone and an application that takes a picture, edits and save an image file by testing not only about a DQT information but also a information of Thumbnail image. Second, the research will build a database of DQT and Thumbnail information in JPEG file to find more accurate image file's origin.

• Journal of Internet Computing and Services
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• v.7 no.3
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• pp.107-118
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• 2006

Recently, network infra grows rapidly and the digital image compression technique have made remarkable progress, and therefore the demand of the real-time image surveillance system which uses a network camera server is increasing. Network Camera Server has emerged as an attractive alternative to the CCTV for the real-time image surveillance. From this reason, the demand regarding the development of the real-time image surveillance system which uses a network camera server is increasing as well. In this paper, we will provide a model for JPEG Streamer which is used in real-time image surveillance system. And we will design and implement this model. For the stability and efficiency of the JPEG Streamer, we'll use the thread pool and shared memory. We will also introduce the concept of double buffering for increasing the quality of real-time image, Using the JPEG Streamer, a raising of the productivity, reliability and stability will be able to secure to development of real-time image surveillance system.

• The KIPS Transactions:PartB
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• v.19B no.2
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• pp.83-92
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• 2012

Multimedia contents can be copied and manipulated without quality degradation. Therefore, they are vulnerable to digital forgery and illegal distribution. In these days, with increasing the importance of multimedia security, various multimedia security techniques are studied. In this paper, we propose a content authentication algorithm based on reversible watermarking which supports JPEG compression commonly used for multimedia contents. After splitting image blocks, a specific authentication code for each block is extracted and embedded into the quantized coefficients on JPEG compression which are preserved against lossy processing. At a decoding process, the watermarked JPEG image is authenticated by extracting the embedded code and restored to have the original image quality. To evaluate the performance of the proposed algorithm, we analyzed image quality and compression ratio on various test images. The average PSNR value and compression ratio of the watermarked JPEG image were 33.13dB and 90.65%, respectively, whose difference with the standard JPEG compression were 2.44dB and 1.63%.