• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.3C
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• pp.297-305
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• 2007

In the paper, a Motion JPEG2000 coder which has been set as the standard for image compression by the Digital Cinema Initiatives (DCI), an organization composed of major movie studios was implemented into a target FPGA. The DWT (Discrete Wavelet Transform) based on lifting and the Tier 1 of EBCOT (Embedded Block Coding with Optimized Truncation) which are major functional modules of the JPEG2000 were setup with dedicated hardware. The Tier 2 process was implemented in software. For digital cinema the tile-size was set to support $1024\times1024$ pixels. To ensure the real-time operations, three entropy encoders were used. When Verilog-HDL was used for hardware, resources of 32,470 LEs in Altera's Stratix EP1S80 were used, and the hardware worked stably at the frequency of 150Mhz.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.1
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• pp.56-63
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• 2009

Nowdays, Most of Internet Contents delivered as a compressed file. It gives many advantages like deduction of communication bandwidth and transmission time etc. In case of JPEG Compression, Quantization is the most important procedure which accomplish the compression. In general signal processing, Quantization is the process which converts continuous analog signal to discrete digital signal. As you known already, Quantization over JPEG compression is to reduce magnitude of pixel value in spatial domain or coefficient in frequency domain. A lot of Data Hiding algorithms also developed to applicable for those compressed files. In this paper, we are going to unveil the influence of quantization table which used in the process of JPEG compression. Even thought most of algorithm modify frequency coefficients with considering image quality, they are ignoring the influence of quantization factor corresponding with the modified frequency coefficient. If existing algorithm adapt this result, they can easily evaluate their performances.

• Korean Journal of Digital Imaging in Medicine
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• v.6 no.1
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• pp.31-40
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• 2003

Purpose : In a PACS(Picture Archiving Communications System) environment, which is a very important component in a digital medical environment, the compression of digital medical images is a necessary and effective feature. In a current system where JPEG is applied to the compression of medical images, this study is to examine effectiveness and suitability when the JPEG2000, a more advanced compression algorithm for still images, is applied to the compression of medical images. In this thesis, we attempt to address the compressibility for effective clinical usage when compressing medical images, applying the objectivization of clinical evaluation as a function of compressibility. In the experiment al method, the compression was applied at a fixed rate using JPEG2000, and the n the result was compared with compressed images by JPEG. Method : For the performance evaluation, we choose SNR(Signal to Noise Ratio) measurement of an objective evaluation of definition and analyze a subjective evaluation by the ROC(Receiver Operating Characteristic) method. The results of the experiment showed that in the case of JPEG2000 there is hardly any distortion of images, even at high compression ratio(100:1), while regarding noise, the SNR remains around about 40dB, which is also relatively high. Before reading by reference to evaluative materials concerning objective compressed images, it is impossible to apply high compression to images : however, after reading, this can be applied to images that have already existed for some time.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2006.11a
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• pp.101-109
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• 2006

현재 디지털 시네마의 압축 표준으로는 DCI(Digital Cinema Initiatives)에 의해 정지 영상 압축의 국제 표준인 JPEG-2000이 선정되어 있다. 하지만 영상 압축에 있어 또 하나의 국제 표준인 H.264/AVC는 현재까지 동영상 압축에 있어 과거 어떤 동영상 압축 코덱보다 큰 효율을 달성해왔다. 본 논문에서는 이 두 가지 압축 방법을 사용하여 디지털 시네마 압축에서 요구하는 시각적 무손실 압축을 연구하였다. 즉 실험 영상에 다양한 파라메터 값으로 JPEG-2000과 H.264/AVC 압축을 수행 하였고 산출된 결과를 시각적 무손실 압축의 환경 조건하에서 제시하였다. JPEG-2000의 경우 RATE 0.02, 0.03 이전의 PSNR 변화 값이 낮은 편이었으며, DCI 규격에도 만족시키는 결과를 보여주었다. H.264의 경우 압축 성능에 있어서 JPEG-2000보다 다소 우월한 결과를 보여주었다. 계층적 코딩을 통해 매체간 높은 호환성을 보장하는 H.264/AVC의 장점은 디지털 시네마의 배포에 적용 가능함을 함께 고려할 때 JPEG-2000과 함께 디지털 시네마를 위한 압축 표준으로 고려해 볼 만 하다.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.3
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• pp.201-207
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• 2008

This paper presents the implementation of a Tiling System about Preprocessing functions of JPEG 2000. The system covers the JPEG 2000 standard and is designed to determine the size of the image, to expand the image area and to split input image into several tiles. In order to split the input image with the progressive transmission into several tiles and transmit a tile of this image to others, this system store this image into Frame Memory. Therefore, this is designed as the Finite State Machine (FSM) to sequence through specific patterns of states in a predetermined sequential manner by using Verilog-HDL and be designed to handle a maximum 5M image. Moreover, for identifying image size for expansion, we propose several formula which are based on remainder after division (rem). we propose the true table which determines the size of the image input patterns by using results of these formula. Under the condition of TSMC 0.25um ASIC library, gate count is 18,725 and maximum data arrival time is 18.94 [ns].

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.11
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• pp.101-108
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• 2007

In this paper, we propose and verify an adaptive block watermarking algorithm based on JPEG2000 DWT, which determines watermarking for the original image by two scaling factors in order to overcome image degradation and blocking problem at the edge. Adaptive block watermarking algorithm uses 2 scaling factors, one is calculated by the ratio of present block average to the next block average, and the other is calculated by the ratio of total LL subband average to each block average. Signals of adaptive block watermark are obtained from an original image by itself and the strength of watermark is automatically controlled by image characters. Instead of conventional methods using identical intensity of a watermark, the proposed method uses adaptive watermark with different intensity controlled by each block. Thus, an adaptive block watermark improves the visuality of images by 4$\sim$14dB and it is robust against attacks such as filtering, JPEG2000 compression, resizing and cropping. Also we implemented the algorithm in ASIC using Hynix 0.25${\mu}m$ CMOS technology to integrate it in JPEG2000 codec chip.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.49-58
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• 2005

In this paper, we proposed a blind watermarking algerian to use characteristics of a scalar quantizer which is the recommended in the JPEG2000 and JPEG. The proposed algorithm shifts a quantization index according to the value of each watermark bit to prevent losing the watermark information during the compression by quantization. Therefore, the watermark is embedded during the process of quantization, not an additional process for watermarking, and is adaptively applied as a assigned quantizer according application areas. Before embedding process, a LFSR(Linear feedback shift register) rearranged the watermark for the security of the watermark itself and in the embedding process, a LFSR is used to hide the watermarking positions. Therefore the embedded watermark can he extracted by only the owner who knows the initial value of LFSR without the original image. The visual recognizable pattern such as a binary image was used as the watermark. The experimental results showed that the proposed algerian satisfies the robustness and imperceptibility corresponding to the major requirement of watermarking. The results showed the largest error rate to be $5.7\%$ for attack. The experimental result which compares the proposed algorithm with the Mohamed algorithm showed that the proposed algorithm was better than it, exactly $4\~5$ times for the attacks of JPEG and JPEG2000.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.1
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• pp.189-196
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• 2024

Currently, it is almost impossible to move the focus of a previously taken photo to a different location. This paper challenges a technology that can move the focus of a captured photo to another location after shooting. To achieve this goal, this paper proposed and implemented a method for taking photos with various focuses at the moment the camera took pictures and storing them in a single JPEG file to extract photos focused on the user's preferred location. In this paper, two methods are implemented: taking various photos by quickly moving the focal length of the lens from close to far away, and taking various photos focused on each object by recognizing objects in the camera viewfinder. Various photos taken are stored in a single JPEG to maintain compatibility with traditional photo viewers. At this time, this JPEG file used the All-in-JPEG format proposed in previous research to store a variety of images. This paper verified its practicality by implementing these technologies in an Android app named OnePIC.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.2
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• pp.35-40
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• 2024

In this paper, we validate the practicality of the OnePIC app implemented in the previous study by analyzing the execution and storage performance. The OnePIC app is a camera app that allows you to get a photo with a desired focus after taking photos focused on various places. To evaluate performance, we analyzed distance focus shooting time and object focus shooting time in detail. The performance evaluation was measured on actual smartphone. Distance focus shooting time for 5 photos was around 0.84 seconds, the object detection time was around 0.19 seconds regardless of the number of objects and object focus shooting time for 5 photos was around 4.84 seconds. When we compared the size of a single All-in-JPEG file that stores multi-focus photos to the size of the JPEG files stored individually, there was no significant benefit in storage space because the All-in-JPEG file size was subtly reduced. However, All-in-JPEG has the great advantage of managing multi-focus photos. Finally, we conclude that the OnePIC app is practical in terms of shooting time, photo storage size, and management.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.3
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• pp.37-43
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• 2009

The new still image compression standard JPEG2000 is consisted of DWT and EBCOT. In this paper, proposed and designed new algorithm in efficient EBCOT. BPC based on the contort. Proposed BPC Algorithm is forecasted coding pass using Sigstage, column, mpass value. BAC design apply 4-pipeline stage. EBCOT designed using Verilog HDL. Verification and Synthesis using Xillinx FPGA technology.