• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.9
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• pp.2351-2369
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• 2012

This paper describes interpolation method of motion field in the Wyner-Ziv video coding (WZVC) based on Expectation-Maximization (EM) algorithm. In the EM algorithm, the estimated motion field distribution is calculated on a block-by-block basis. Each pixel in the block shares similar probability distribution, producing an undesired blocking artefact on the pixel-based motion field. The proposed interpolation techniques are Bicubic and Lanczos which successively use 16 and 32 neighborhood probability distributions of block-based motion field for one pixel in k-by-k block on pixel-based motion field. EM-based WZVC codec updates the estimated probability distribution on block-based motion field, and interpolates it to pixel resolution. This is required to generate higher-quality soft side information (SI) such that the decoding algorithm is able to make syndrome estimation more quickly. Our experiments showed that the proposed interpolation methods have the capability to reduce EM-based WZVC decoding complexity with small increment of bit rate.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.614-616
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• 2010

Recently, there is increasing concern about smart phone due to the release of iPhone and Android phone. So, There are many kinds of application in smart phone, and applications using multimedia contents is increasing. The famous codecs for Image and video are JPEG, MPEG and h.264, which is popular recently as a vedeo codec because of its high compression ratio compared with the other video codecs. In this paper, we will divide Jpeg Sequence to each Jpeg and will display that Jpeg looks like a video continuously in Android. And we will show you the simulation result.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.585-588
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• 2010

Recently, there is increasing concern about smart phone due to the release of Iphone and Android phone. Like the normal desktop application, using multimedia contents will have important role for smart phone application. The multimedia contents mentioned here mean Image and Video. The famous codecs for Image and video are Jpeg Mpeg and h.264, which is popular recently as a vedeo codec because of its high compression ratio compared with the other video codecs. In this paper, we will use Jpeg and H.264 encoded raw sequences. This paper will suggest how to decode and display effectively Jpeg and H.264 raw sequences arrived from socket stream. And we will show you the simulation result.

• Journal of Broadcast Engineering
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• v.19 no.6
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• pp.836-846
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• 2014

To expedite UHD (Ultra High Definition) video service, the HEVC (High-Efficiency Video Coding) technology has recently been standardized and it achieves two times higher compression efficiency than the conventional H.264/AVC. To obtain the improved efficiency, however, it employs many complex methods which need complicated calculation, thereby resulting in a significantly increased computational complexity when compared to that of H.264/AVC. For example, to improve the coding efficiency of intra frame coding, up to 35 intra prediction modes are defined in HEVC, but this results in an increased encoding time than the H.264/AVC. In this paper, we propose a fast intra prediction mode decision scheme which reduces computational complexity by changing the number of intra prediction mode in accordance with the percentage of PU sizes for a given video resolution, and by classifying the 35 intra prediction modes into 4 categories considering video resolution and quantization parameter. The experimental results show that the total encoding time is reduced by about 7% on average at the cost of only 2% increase in BD-rate.

• The Journal of the Korea Contents Association
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• v.7 no.4
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• pp.192-198
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• 2007

Due to the development of information telecommunication technology, e-learning industry is rapidly expanding its scope along with its production technology. The recent trend of e-learning program is likely converted from Wmv(Window Media Video) of Microsoft to Flv(Flash video), which has less capacity but better quality than other image file. It has successfully drawn the users attention since Flv can operate at most OS environments and browsers let alone with window and Lenux without extra players and codec setup. However, there is no accurate data on comparative analysis between Wmv and Flv regarding capacity, quality and production time. Therefore, the study shows the comparative data analysis on Wmv and Flv so as to set out production platform up to its idiosyncrasy.

• Journal of Internet Computing and Services
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• v.11 no.2
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• pp.143-153
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• 2010

When providing high quality panoramic video across the Internet, mobile communications, and broadcasting areas, it requires a suitable video codec that satisfies both high-compression efficiency and random access functionality. The users must have high-compression efficiency in order to enable video streaming of high-volume panoramic data. Random access allows the user to move the viewpoint and direction freely. In this paper, we propose the parallel processing scheme under cell units in order to improve the performance of streaming service for large screen panoramic video in 10Mbps bandwidths based on H.264/AVC with high compression rate. This improved algorithm divides a screen composed of cells less than $256{\times}256$ in size, encodes it, and decodes it with the cells in the present view. At this point, encoding/decoding is parallel processed by the present cell units. Also, since the cells only included in the present view are packed and transmitted, the possible processing of not extricating blocks is proven by experiment.

• The KIPS Transactions:PartB
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• v.10B no.2
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• pp.189-196
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• 2003

This paper describes an error resilient video data transmission method using information hiding. In order to localize transmission errors in receiver, video encoder embeds one bit for a macro block during encoding process. Embedded information is detected during decoding process in the receiver, and the transmission errors can be localized by comparing the original embedding data. The localized transmission errors can be easily corrected, thus the degradation in a reconstructed image can be alleviated. Futhermore, the embedded information can be applied to protect intellectual property rights of the video data. Experimental results for 3 QCIF sized video sequenced composed of 150 frames respectively show that, while degradation in video streams in which the information is embedded is negligible, especially in a noisy channel, the average PSNR of reconstructed images can be improved about 5 dB by using embedded information. Also, intellectual property rights information can be effectively obtained from reconstructed images.

• Journal of Broadcast Engineering
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• v.13 no.1
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• pp.162-173
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• 2008

In this paper, we propose an effective stereo-view video coding method that considers stereo-view and displayer characteristics. Current many stereo video displayers are designed for not only stereo display but also conventional single view display. In these systems, the resolution of two input videos for a stereo mode is half of that of single view for compatibility with conventional single view video services. In this raper, we propose a stereo video codec to deal with both single view and stereo view services by encoding whole left image and down-sampled right image. However, direct disparity estimation is not possible between two views because the resolution of a left image is different from that of the corresponding right image. So, we propose a disparity estimation method to make use of full information of the left reference image without down-sampling. In experimental result, we achieved $0.5{\sim}0.8\;dB$ coding gain, compared with several conventional algorithms.

• Journal of Korean Society of Archives and Records Management
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• v.24 no.1
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• pp.163-186
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• 2024

With the National Archives of Korea's establishment of the Selection Criteria for Preservation Format of Digital Records (v1.0) in 2022, criteria have been formed to facilitate the selection of appropriate preservation formats for various types of digital records. With the advancement of technology, diverse electronic file types are produced. However, no specific criteria exist for records other than document types, such as PDF/A-1b. Therefore, the purpose of this paper is to derive intrinsic criteria for selecting preservation formats for audiovisual records, particularly focusing on video-type digital records, to expand the scope of the preservation format selection criteria. Initially, significant properties of video-type digital records were determined, forming the basis for the intrinsic criteria. According to these properties, the video types were categorized into container type and codec type, and three and six evaluation criteria items were derived, respectively. By structuring evaluation criteria for each attribute, this paper proposes intrinsic criteria for selecting preservation formats for video-type electronic records.

• Journal of Broadcast Engineering
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• v.10 no.4 s.29
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• pp.528-539
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• 2005

The H.264 has been adopted as the video codec for various multimedia services such as DMB and next-generation DVD because of its superior coding performance. However, the reference codec of the standard, the joint model (JM) contains quite a few algorithms which are too complex to be used for the resource-constraint embedded environment. This paper introduces very low-complexity H.264 encoding algorithm which is applicable for the embedded environment. The proposed algorithm was realized by restricting some coding tools on the basis that it should not cause too severe degradation of RD-performance and adding a few early termination and bypass conditions during the motion estimation and mode decision process. In case of encoding of 7.5fps QCIF sequence with 64kbpswith the proposed algorithm, the encoder yields worse PSNRs by 0.4 dB than the standard JM, but requires only $15\%$ of computational complexity and lowers the required memory and power consumption drastically. By porting the proposed H.264 codec into the PDA with Intel PXA255 Processor, we verified the feasibility of the H.264 based MMS(Multimedia Messaging Service) on PDA.