• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.1
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• pp.61-67
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• 2011

In this paper, a new method for effective video coding is studied. Picture set filter is proposed for preserving compression ratio and video quality. This filter controls the compression ratio of each frame depending on the correlation to the reference frame by selectively eliminating less important high-resolution areas. Consequently, video quality can be preserved and bit rate can be controlled adaptively. In the simulation, to test the performance of the proposed coding method, comparisons with the full search block matching algorithm and the differential image coding algorithm are made. In the former case, video quality, compression ratio and encoding time is improved. In the latter case, video quality is degraded, but compression ratio and encoding time is improved. Consequently, the proposed method shows a reasonably good performance over existing ones.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.250-252
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• 2022

As immersive video contents have started to emerge in the commercial market, research on it is required. For this, efficient coding methods for immersive video are being studied in the MPEG-I Visual workgroup, and they released Test Model for Immersive Video (TMIV). In current TMIV, the patches are packed into atlas in order of patch size. However, this simple patch packing method can reduce the coding efficiency in terms of 2D encoder. In this paper, we propose patch packing method which pack the patches into atlases by using the similarity of each patch for improving coding efficiency of 3DoF+ video. Experimental result shows that there is a 0.3% BD-rate savings on average over the anchor of TMIV.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1995.06a
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• pp.97-100
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• 1995

In transmission of image sequences over ATM networks, the packet loss problem and channel sharing efficiency are important. As a possible solution two-layer video coding methods have been proposed. These methods transmit video information over the network with different levels of protection with respect to packets loss. In this paper, a two-layer coding method using pyramid structure is proposed and several realizations of two-layer video coding methods are presented and their performances are compared.

• 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 Broadcast Engineering
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• v.14 no.5
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• pp.601-615
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• 2009

This paper proposes an efficient depth-map coding method for generating virtual-view images in 3D-Video. Virtual-view images can be generated by the view-interpolation based on the depth-map of the image. A conventional video coding method such as H.264 has been used. However, a conventional video coding method does not consider the image characteristics of the depth-map. Therefore, this paper proposes an adaptive depth-map coding method that can select between the H.264/AVC coding scheme and the proposed gray-coded bit plane-based coding scheme in a unit of block. This improves the coding efficiency of the depth-map data. Simulation results show that the proposed method, in comparison with the H.264/AVC coding scheme, improves the average BD-rate savings by 7.43% and the average BD-PSNR gains by 0.5dB. It also improves the subjective picture quality of synthesized virtual-view images using decoded depth-maps.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.1
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• pp.56-67
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• 2013

Because H.264/SVC can meet the needs of different networks and user terminals, it has become more and more popular. In this paper, we focus on the spatial resolution scalability of H.264/SVC and propose a blind video watermarking algorithm for the copyright protection of H.264/SVC coded video. The watermark embedding occurs before the H.264/SVC encoding, and only the original enhancement layer sequence is watermarked. However, because the watermark is embedded into the average matrix of each macro block, it can be detected in both the enhancement layer and base layer after downsampling, video encoding, and video decoding. The proposed algorithm is examined using JSVM, and experiment results show that is robust to H.264/SVC coding and has little influence on video quality.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.3
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• pp.119-126
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• 2013

Achieve real-time encryption and video data transcoding, current video encryption methods usually integrate encryption algorithm with video compression course. This paper is devoted to discussing the video encryption technology, by encrypting to avoid unauthorized person getting video data. This paper studied the H.264 entropy coding and proposed of CAVLC video encryption scheme which is combined with the process of entropy coding of H.264 CAVLC encryption scheme. Three encryption levels are proposed. In addition, a scrambling method is also proposed which makes the encrypted frames more robust in anti crack. This method showed more robust video data encryption function and compressive rate.

• 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.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.1
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• pp.128-138
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• 2010

In this paper, we propose a new bit assignment scheme for Wyner-Ziv video coding. Distributed video coding (DVC) is a new video coding paradigm which enables greatly low complexity encoding because it does not have any motion prediction module at encoder. Therefore, it is very well suited for many applications such as video communication, video surveillance, extremely low power consumption video coding, and other portable applications. Theoretically, the Wyner-Ziv video coding is proved to achieve the same rate-distortion (RD) performance comparable to that of the joint video coding. However, its RD performance has much gap compared to MC-DCT-based video coding such as H.264/AVC. Moreover, Transform Domain Wyner-Ziv (TDWZ) video coding which is a kind of DVC with transform module has difficulty of exact bit assignment because the entire image is treated as a same message. In this paper, we propose a feasible bit assignment algorithm using adaptive quantization matrix selection for the TDWZ video coding. The proposed method can calculate suitable bit amount for each region using the local characteristics of image. Simulation results show that the proposed method can enhance coding performance.

• ETRI Journal
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• v.26 no.4
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• pp.332-343
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• 2004

One of the recent and most significant technical properties can be expressed as "digital convergence," which is helping lead the technical paradigm into a ubiquitous environment. As an initial trial of realizing a ubiquitous environment, the convergence between broadcasting and telecommunication fields is now on the way, where it is required to develop a scalable video coding scheme for one-source and multi-use media. Traditional scalable video coding schemes have, however, limitations for higher stable picture quality especially on the region of interest. Therefore, this paper introduces an adaptive scanning method especially designed for a higher regional-stable picture quality under a ubiquitous video coding environment, which can improve the subjective quality of the decoded video by most-preferentially encoding, transmitting, and decoding the top-priority image information of the region of interest. Thus, the video can be more clearly visible to users. From various simulation results, the proposed scanning method in this paper can achieve an improved subjective picture quality far better than the widely used raster scan order in conventional video coding schemes, especially on the region of interest, and without a significant loss of quality in the left-over region.