• 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%.

• Journal of Korea Multimedia Society
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• v.11 no.5
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• pp.579-587
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• 2008

Typically, the file sizes of JPEG compressed images with various complexity differ from images regardless of same image size. So, it is not easy to estimate the remaining image counts that should be stored in the limited storage equipped with the digital camera. To solve the problem, the bit rate control employs the modification of quantization table. The previous work assumed that there is linear relation between image activity and modification factor of quantization table, but in this paper, more accurate functional relations based on statistics are employed to improve the bit rate control accuracy. Computer simulations reveals that the standard deviation of the bit rate error of the proposed scheme is 50% less than that of the conventional method.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.466-469
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• 2009

This paper presents a modified QIM-JPEG2000 steganography which improves the previous JPEG2000 steganography using quantization index modulation (QIM). Post-embedding changes in file size and PSNR by the modified QIM-JPEG2000 are smaller than those by the previous QIM-JPEG2000. Steganalysis experiments to determine whether messages are embedded in given JPEG2000 images show that the modified QIM-JPEG2000 is more secure than the previous QIMJPEG2000.

• Electronics and Telecommunications Trends
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• v.38 no.2
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• pp.66-74
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• 2023

Holography is the most promising 3D imaging technology to faithfully record and reproduce light information. In addition, it is widely explored in metrology for applications such as microscopy and tomography because it can accurately measure 3D shapes. However, the data size of a digital hologram is very large, and the data characteristics are notably different from those of conventional 2D images. The Joint Photographic Experts Group (JPEG) is a group of experts from the International Organization for Standardization/International Electrotechnical Commission. This group develops and maintains standards for still image compression. In 2014, the JPEG released a new standard for 3D image compression called JPEG Pleno to represent light fields, point clouds, and holograms. Among them, JPEG Pleno Holography is the first international standard for hologram compression. We review recent advances in JPEG Pleno Holography standardization and discuss future directions of development.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.5
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• pp.14-22
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• 2007

PACS is an integrated communication network system which is consists of image acquisition devices, storage archiving units, display stations, computer processors, and database management systems. In medical industry, they have been introduced the medical equipments through PACS systems based on the DICOM standard. In this paper, we have reviewed the visual quality performance of various JPEG and JPEG2000 compression options for medical images. Through the realized the transmission mode on DICOM standard, the developed DICOM viewer has been shown in medical applications.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1662-1665
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• 2004

A real-time joint transform correlator by using JPEG-compressed reference images is proposed as practical solution to storage problem and improvement of processing time of automatic target recognition system [1]. Effects of compression on recognition performance of join transform correlator are quantitatively investigated under situations where the target is suffered from noise and has contrast difference with respect to the reference. Two images with different spatial-frequency contents and contrast were used as the test scenes. The simulation results show that, the recognition performance of joint transform correlator by using the compressed reference images with high spatial-frequency components is more sensitive to noise and contrast difference than the low spatial-frequency image.

• 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.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.1368-1370
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• 1996

The Information of Edges which takes small area comparing with the total image is very important in DNA images as well as general images. DNA image is the object should be managed by computing and it's demanding information is less than general images, but the accuracy is more important In a huge DNA image processing system such as DNA Information Bank, the performance depends on the size of image. In this paper, we extract the edge information and make it as a binary image. To reduce the size of the original image, it was applied by JPEG image compression method. The compressed image is combined with edge information when they are restored. As a result, Both the image compression ratio and restoration quality are optimized without the loss of critical information.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.1
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• pp.404-421
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• 2020

A reversible data hiding scheme in JPEG compressed bitstreams is proposed, which could avoid decoding failure and file expansion by means of removing of bitstreams corresponding to high frequency coefficients and embedding of secret data in file header as comment part. We decode original JPEG images to quantified 8×8 DCT blocks, and search for a high frequency as an optimal termination point, beyond which the coefficients are set to zero. These blocks are separated into two parts so that termination point in the latter part is slightly smaller to make the whole blocks available in substitution. Then spare space is reserved to insert secret data after comment marker so that data extraction is independent of recovery in receiver. Marked images can be displayed normally such that it is difficult to distinguish deviation by human eyes. Termination point is adaptive for variation in secret size. A secret size below 500 bits produces a negligible distortion and a PSNR of approximately 50 dB, while PSNR is also mostly larger than 30 dB for a secret size up to 25000 bits. The experimental results show that the proposed technique exhibits significant advantages in computational complexity and preservation of file size for small hiding capacity, compared to previous methods.

• Journal of the Korea Society of Computer and Information
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• v.13 no.6
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• pp.127-136
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• 2008

A digitized image passes by encoding, storing or transmitting to show it to users. In this process, may be users would want to see a specific region of the image. And depending on the system features or in the case that the resolution of the image is large, it will take a huge time that the image show to the users. In this time, it will be resonable that the part users want to see shows earlier and afterward the other parts show. For this, JPEG2000 standards provide ROI. Although ROI extraction that users specify ROI arbitrarily is the best, people not always participate in doing all the images. There needs an automatic ROI extracting and storing in some images. JPEG2000 should extract and send an ROI automatically when the images is encoded without ROI. This study proposes a method that automatically extracts an ROI, makes the ROI masks, transfers the masked image preferentially and the background. And the study compares and experiments the proposed method and the method not having ROI.