• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.10
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• pp.156-165
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• 1998

In this paper, the hybrid algorithm for the scene change detection of MPEG-based compressed video data is proposed. There have been two methods to detect scene changes of video data compressed using algorithms such as MPEG or motion-JPEG: analyzing the compressed data directly, and analyzing from the retrieved data. The former has the advantage of taking less time, while the latter can obtain detail results at the expense of time and memory. Thus by combining each algorithm we detect cuts from compressed sequence, retrieve data for some selected region, and detect gradual scene changes. Simulation results verify the superiorities of the proposed algorithm in analyzing time and accuracy.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.1A
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• pp.89-97
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• 2002

This paper proposes the adaptive digital watermarking method for the ownership protection of images. The watermarks are inserted to a selected area rather than a whole area. The proposed method reduces the distortion caused by the watermarking process. To select the regions, roughness of the image should be considered because the watermarks in the smooth regions are easily detected through the human eyes. To find the rough regions, Discrete Cosine Transform (DCT) method is used. Generally, the high frequency regions of images are lost by the compression process such as JPEG. So, the watermarks are inserted to the low frequency regions of a selected area by using the proposed method. The proposed method reduce the image loss or distortion brought by the image processing, such as compression, filtering, scaling, addition of noise, cropping, and wavelet transform.

• Annual Conference of KIPS
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• 2000.10b
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• pp.1263-1266
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• 2000

In this paper, we propose a reliable Image transmission system with Decision Feedback Equalization (DFE), and use diversity combining techniques over multipath fading channels. It is shown that the proposed system has the features of simplicity in implementation with DFE and diversity combining techniques without modifying DFE. This study includes error concealment techniques for reconstruction of missing blocks in JPEG. To verify and compare the performance of our proposed system, the computer simulations have been performed in three diversity combining cases.

• ETRI Journal
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• v.37 no.3
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• pp.595-605
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• 2015

This paper proposes a robust, imperceptible block-based digital video watermarking algorithm that makes use of the Speeded Up Robust Feature (SURF) technique. The SURF technique is used to extract the most important features of a video. A discrete multiwavelet transform (DMWT) domain in conjunction with a discrete cosine transform is used for embedding a watermark into feature blocks. The watermark used is a binary image. The proposed algorithm is further improved for robustness by an error-correction code to protect the watermark against bit errors. The same watermark is embedded temporally for every set of frames of an input video to improve the decoded watermark correlation. Extensive experimental results demonstrate that the proposed DMWT domain video watermarking using SURF features is robust against common image processing attacks, motion JPEG2000 compression, frame averaging, and frame swapping attacks. The quality of a watermarked video under the proposed algorithm is high, demonstrating the imperceptibility of an embedded watermark.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.187-194
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• 2011

In this paper, JPEG(Joint Photographic Experts Group) image data video decoding technique is presented, it is Huffman decoding method and fractal image method which is very complexive algorithm and the time required much it to implement this method and the first image is decoded to video frame image. This have defect of overlap decoding and transport work because of impossible to represent objective value of resemblance. The proposed method was calculated the mathematical absolute image resemblance and simplify the moving picture process to reducing the step of moving picture codefying. The results show that smoothed moving picture compared recent methods.

• Journal of the Korea Society of Computer and Information
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• v.8 no.3
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• pp.61-65
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• 2003

In this paper, a novel watermarking technique that based on wavelet packet transform using PIM is proposed for the copyright of the digital images. We divide wavelet packet coefficients into detailed blocks and calculate the complexity of each block using PIM. Because human is impervious to the change in the complex area, the embedding watermark to the selected coefficients using PIM enhances invisibility. From the experimental results, the proposed algorithm shows better invisibility and robustness performance in a general signal processing such as JPEG and SPIHT lossy compression, median filtering. Especially, it demonstrates better performance for the low bit-rate compression in the images that include many high frequency components.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.3
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• pp.1-8
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• 2008

In the event of a traffic accident, a fire accident, or a criminal act, anyone will be able to capture these important moments and use authentic photographs for evidence purposes. Digital watermarking is able to ensure that the digital photographs taken from a particular camera-phone are authentic and indeed. This paper presents a blind image watermarking technique for digital phone camera. This method is based on singular value decomposition (SVD) and wavelet decomposition. Experimental results show that the proposed technique performs well in security and robustness against JPEG compression.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.1C
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• pp.62-67
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• 2008

In this paper, wavelet based blind watermarking using self-reference method is proposed. First, we process wavelet transform of original image. Then, we set all domain except for the low-frequency domain to zero and make self-reference image after wavelet reverse transformation. By choosing specific domain according to the pixel value difference between original image and self-reference image, we make random sequence, use as watermark and embed. The experimental results of the watermark embedding and extraction on various images show that the proposed scheme not only has good image quality, but also has stability on JPEG lossy compression, filtering, sharpening, blurring and noise.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.1C
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• pp.68-78
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• 2008

The transmission of multimedia information over error-prone channels such as wireless networks has become an important area of research. In this paper, we propose two Error Concealment(EC) schemes for wireless transmission of JPEG2000 image. The Multiple Representation(MR) is employed as the preprocessing in our schemes, whereas the main error concealing operation is applied in wavelet domain at receiver side. The compressed code-stream of several subsampled versions of original image is transmitted over a single channel with random bit errors. In the decoder side, the correctly reconstructed wavelet coefficients are utilized to recover the corrupted coefficients in other sub-images. The recovery is carried out by proposed basic(MREC-BS) or enhanced(MREC-ES) methods, both of which can be simply implemented. Moreover, there is no iterative processing during error concealing, which results a big time saving. Also, the simulation results confirm the effectiveness and efficiency of our proposed schemes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1C
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• pp.105-112
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• 2009

In this paper, we propose a digital watermarking method using Multi-resolution Characteristic of 2D CAT (2D cellular automata transform). Firstly, we select the gateway values to generate a basis function and the basis function transforms images into cellular automata space. Then, we embed the random bit sequence as watermark in specific parts of cellular automata transform coefficients. The proposed method not only verifies higher fidelity than the existing method but also stronger stability on JPEG lossy compression, filtering, sharpening and noise through tests for robustness. Moreover, the proposed scheme allows only one 2D CAT basis function per gateway value. Since there are $2^{96}$ possible gateway values.