• Journal of Broadcast Engineering
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• v.9 no.3
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• pp.246-256
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• 2004

In this paper, we proposed a new lossless image compression algorithm. Lossless image compression has been used in the field that requires the accuracy and precision. Thus, application areas using medical unaging, prepress unaging, image archival systems, precious artworks to be preserved, and remotely sensed images require lossless compression. The compression ratio from lossless image compression has not been satisfactory, thus far. So, new method of lossless image compression has been investigated to get better compression efficiency. We have compared the compression results with the most typical compression methods such as CALIC and JPEG-LS. CALIC has shown the best compression-ratio among the existing lossless coding methods at the cost of the extensive complexity by three pass algorithm. On the other hand, JPEG-LS's compression-ratio is not higher than CALIC, but was adopted as an international standard of ISO because of the low complexity and fast coding process. In the proposed method, we adopted an adaptive predictor that can exploit the characteristics of individual images, and an adaptive arithmetic coding with multiple probability models. As a result, the proposed algorithm showed 5％ improvement in compression efficiency in comparison with JPEG-LS and showed comparable compression ratio with CALIC.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.11
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• pp.5547-5562
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• 2016

JPEG-LS is an international standard for lossless or near-lossless image-compression algorithms. In this paper, a simple method is proposed to improve the performance of the lossless JPEG-LS algorithm. With respect to JPEG-LS and its supplementary explanation, Golomb-Rice (GR) coding is mainly used for entropy coding, but it is not used for long codewords. The proposed method replaces a set of long codewords with a set of shorter location map information. This paper shows how efficiently the location map guarantees reversibility and enhances the compression rate in terms of performance. Experiments have also been conducted to verify the efficiency of the proposed method.

• Journal of Broadcast Engineering
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• v.13 no.1
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• pp.99-108
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• 2008

This raper analyzes the effect of visually lossless image compression for efficient distribution of digital cinema. Currently, distribution of digital cinema is carried out based on JPEG 2000 standard that has been selected by DCI. We first summarize characteristics of JPEG 2000, and then define the concept of visually lossless coding that plays an important role in digital cinema distribution. We provide a test for JPEG 2000 compression performance according to DCI specification for visually lossless. Based on the experiment, the result satisfies high quality for cinema distribution.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.7
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• pp.1003-1008
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• 2013

This paper proposes a compression scheme based on the modified reversible integer transform (MRIT) and forward adaptive prediction for lossless image compression. JPEG XR is the newest image coding standard with high compression ratio and that composed of the Photo Core Transform (PCT) and backward adaptive prediction. To improve the efficiency and quality of compression, we substitutes the PCT and backward adaptive prediction for the modified reversible integer transform (MRIT) and forward adaptive prediction, respectively. Experimental results indicate that the proposed method are superior to the previous method of JPEG XR in terms of lossless compression efficiency and computational complexity.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1803-1806
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• 2002

This paper describes an effective technique for lossless inter-frame video coding sequences based on a JPEG2000 CODEC. This technique has diminished the compression rate for lossless video coding. In this proposed method, firstly a predicted image for an in- put image is generated by motion estimation(ME), and then a difference image between the input image and the predicted image is calculated, and finally the difference image becomes an input image to a JPEG2000 encoder for lossless coding. Simulation results show the effectiveness of this method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.7C
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• pp.671-680
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• 2009

The diagnostic medical images(CT, MRI) in PACS require large storage and long transmission time. A simple and cheap way of overcoming these limitations is to increase the compression ratio. However, this requires a clinical validation for accurate diagnostic applications. The aim of this paper is to improve the compression efficiency of lossless JPEG2000 for diagnostic CT images by performing a visual-Iossless threshold filtering in high frequency subband. A proposed method, based on 5/3 reversible DWT, provides different subband-threshold values according to the compression ratio and gives the high subjective quality to reconstructed diagnostic CT images.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.268-272
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• 2003

Large medical images in PACS are compressed for saving storage space and improving network speed. The integrated compression environment was designed and developed for uniting of various compression methods. Various compression algorithm-RLE compression, lossless JEPG, JPEG, was built into it, complying with DICOM. A image compression using DWT was also implemented in it. And a unified algorithm of lossless compression and lossy compression was designed to improve images quality and to make compression ratios high. And integrated compression environment was operating together with a database program for efficient and user-friendly management.

• ETRI Journal
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• v.28 no.2
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• pp.260-263
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• 2006

This letter proposes a new near-lossless image compression method with only one line buffer cost for a digital camera with Bayer format image. For such format data, it can provide a low average compression rate (4.24bits/pixel) with high-image quality (larger than 46.37dB where the error of every pixel is less than two). The experimental results show that the near-lossless compression method has better performance than JPEG-LS (lossless) with ${\delta}$ = 2 for a Bayer format image.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.1
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• pp.142-148
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• 2003

We compress medical images in order to solve problems both of request of storage mediums and of a low network speed. In this paper, integration compression environment has been developed for unity of various compression methods. Various compression methods that are implemented by integration compression environment, RLC, Lossless JPEG, and JPEG, comply with the DICOM 3.0. A compression method using DWT is implemented at it. And a unit method of Lossless compression method and lossy compression method is designed to improve images quality and to progress compression ratio. Diverse medical images can be compressed by each compression method. And integration compression environment is operated together database so that information of medical images is administered.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.1
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• pp.45-51
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• 2003

JPEG200, a new international standard for still image compression based on wavelet and bit-plane coding techniques, is developed. In this paper, we design the DWT(Discrete Wavelet Transform) and quantizer for JPEG2000 CODEC. DWT handles both lossy and lossless compression using the same transform-based framework: The Daubechies 9/7 and 5/3 transforms, and quantizer is implemented as SQ(Scalar Quantization). The architecture of the proposed DWT and SQ are synthesized and verified using Xilinx FPGA technology. It operates up to 30MHz, and executes algorithms of wavelet transform and quantization for VGA 10 frame per second.