• Title/Summary/Keyword: 이산웨이블릿변환

Search Result 146, Processing Time 0.021 seconds

An Empirical Digital Image Watermarking using Frequency Properties of DWT (DWT의 주파수 특성을 이용한 실험적 디지털 영상 워터마킹)

  • Kang, I-Seul;Lee, Yong-Seok;Seob), Young-Ho;Kim, Dong-Wook
    • Journal of Broadcast Engineering
    • /
    • v.22 no.3
    • /
    • pp.295-312
    • /
    • 2017
  • Digital video content is the most information-intensive and high-value content. Therefore, it is necessary to protect the intellectual property rights of these contents, and this paper also proposes a watermarking method of digital image for this purpose. The proposed method uses the frequency characteristics of 2-Dimensional Discrete Wavelet Transform (2D-DWT) for digital images and digital watermark on global data without using local or specific data of the image for watermark embedding. The method to insert digital watermark data uses a simple Quantization Index Modulation (QIM) and a multiple watermarking method that inserts the same watermark data in multiple. When extracting a watermark, multiple watermarks are extracted and the final watermark data is determined by a simple statistical method. This method is an empirical method for experimentally determining the parameters in the watermark embedding process. The proposed method performs experiments on various images against various attacks and shows the superiority of the proposed method by comparing the performance with the representative existing methods.

Counterfeit Money Detection Algorithm using Non-Local Mean Value and Support Vector Machine Classifier (비지역적 특징값과 서포트 벡터 머신 분류기를 이용한 위변조 지폐 판별 알고리즘)

  • Ji, Sang-Keun;Lee, Hae-Yeoun
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.2 no.1
    • /
    • pp.55-64
    • /
    • 2013
  • Due to the popularization of digital high-performance capturing equipments and the emergence of powerful image-editing softwares, it is easy for anyone to make a high-quality counterfeit money. However, the probability of detecting a counterfeit money to the general public is extremely low. In this paper, we propose a counterfeit money detection algorithm using a general purpose scanner. This algorithm determines counterfeit money based on the different features in the printing process. After the non-local mean value is used to analyze the noises from each money, we extract statistical features from these noises by calculating a gray level co-occurrence matrix. Then, these features are applied to train and test the support vector machine classifier for identifying either original or counterfeit money. In the experiment, we use total 324 images of original money and counterfeit money. Also, we compare with noise features from previous researches using wiener filter and discrete wavelet transform. The accuracy of the algorithm for identifying counterfeit money was over 94%. Also, the accuracy for identifying the printing source was over 93%. The presented algorithm performs better than previous researches.

Blind Watermarking by Using Circular Input Method and Binary Image (이진영상과 Circular Input 방식을 이용한 Blind 워터마킹)

  • Kim Tae-Ho;Kim Young-Hee;Jin Kyo-Hong;Ko Bong-Jin;Park Mu-Hun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.10 no.8
    • /
    • pp.1407-1413
    • /
    • 2006
  • The field of medical images has been digitalized as the development of computer and the digitalization of the medical instruments. As a result it causes a lot of problems such as an illegal copy related to medical images and property right of the medical images. Therefore, digital watermarking is used for discrimination whether the data are modified or not. It is also used to protect both the property right of medical images and the private life of many patients. The proposed theories, the Non-blind and the Blind method, have two problems. One is needed an original image and the other is using a gaussian watermarking. This paper proposes the new Blind Watermarking using binary images in order to easily recognize the results of watermark. This algorism is described that an watermark of a binary image is wavelet-transformed, and then a transformed watermark is inserted in medium-band of frequency domains of original image by the Circular Input method. This method don't have any loss when image didn't have any attack. As a result Watermark can be perfectly extracted by using this algorithm. And Maximam PSNR value is improved 3.35dB. This algorithm will be improved by using gray level image and color image.

Block-Based Transform-Domain Measurement Coding for Compressive Sensing of Images (영상 압축센싱을 위한 블록기반 변환영역 측정 부호화)

  • Nguyen, Quang Hong;Nguyen, Viet Anh;Trinh, Chien Van;Dinh, Khanh Quoc;Park, Younghyeon;Jeon, Byeungwoo
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.39A no.12
    • /
    • pp.746-755
    • /
    • 2014
  • Compressive sensing (CS) has drawn much interest as a new sampling technique that enables signals to be sampled at a much lower than the Nyquist rate. By noting that the block-based compressive sensing can still keep spatial correlation in measurement domain, in this paper, we propose a novel encoding technique for measurement data obtained in the block-based CS of natural image. We apply discrete wavelet transform (DWT) to decorrelate CS measurements and then assign a proper quantization scheme to those DWT coefficients. Thus, redundancy of CS measurements and bitrate of system are reduced remarkably. Experimental results show improvements in rate-distortion performance by the proposed method against two existing methods of scalar quantization (SQ) and differential pulse-code modulation (DPCM). In the best case, the proposed method gains up to 4 dB, 0.9 dB, and 2.5 dB compared with the Block-based CS-Smoothed Projected Landweber plus SQ, Block-based CS-Smoothed Projected Landweber plus DPCM, and Multihypothesis Block-based CS-Smoothed Projected Landweber plus DPCM, respectively.

An Effective Method to Treat The Boundary Pixels for Image Compression with DWT (DWT를 이용한 영상압축을 위한 경계화소의 효과적인 처리방법)

  • 서영호;김종현;김대경;유지상;김동욱
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.27 no.6A
    • /
    • pp.618-627
    • /
    • 2002
  • In processing images using 2 dimensional Discrete Wavelet Transform(2D-DWT), the method to process the pixels around the image boundary may affect the quality of image and the cost to implement in hardware and software. This paper proposed an effective method to treat the boundary pixels, which is apt to implement in hardware and software without losing the quality of the image costly. This method processes the 2-D image as 1-D array so that 2-D DWT is performed by considering the image with the serial-sequential data structure (Serial-Sequential Processing). To show the performance and easiness in implementation of the proposed method, an image compression codec which compresses image and reconstructs it has been implemented and experimented. It included log-scale fried quantizer, but the entropy coder was not implemented. From the experimental results, the proposed method showed the SNR of almost the same SNR(Signal to Noise Ratio) to the Periodic Expansion(PE) method when the compression ratio(excluding entropy coding) of 2:1, 15.3% higher than Symmetric Expansion(SE) method, and 9.3% higher than 0-pixel Padding Expansion(ZPE) method. Also PE method needed 12.99% more memory space than the proposed method. By considering only the compression process, SE and ZPE methods needed additional operations than the proposed one. In hardware implementation, the proposed method in this paper had 5.92% of overall circuit as the control circuit, while SE, PE, and ZPE method has 22%, 21,2%, and 11.9% as the control circuit, respectively. Consequently, the proposed method can be thought more effective in implementing software and hardware without losing any image quality in the usual image processing applications.

Design Space Exploration of Embedded Many-Core Processors for Real-Time Fire Feature Extraction (실시간 화재 특징 추출을 위한 임베디드 매니코어 프로세서의 디자인 공간 탐색)

  • Suh, Jun-Sang;Kang, Myeongsu;Kim, Cheol-Hong;Kim, Jong-Myon
    • Journal of the Korea Society of Computer and Information
    • /
    • v.18 no.10
    • /
    • pp.1-12
    • /
    • 2013
  • This paper explores design space of many-core processors for a fire feature extraction algorithm. This paper evaluates the impact of varying the number of cores and memory sizes for the many-core processor and identifies an optimal many-core processor in terms of performance, energy efficiency, and area efficiency. In this study, we utilized 90 samples with dimensions of $256{\times}256$ (60 samples containing fire and 30 samples containing non-fire) for experiments. Experimental results using six different many-core architectures (PEs=16, 64, 256, 1,024, 4,096, and 16,384) and the feature extraction algorithm of fire indicate that the highest area efficiency and energy efficiency are achieved at PEs=1,024 and 4,096, respectively, for all fire/non-fire containing movies. In addition, all the six many-core processors satisfy the real-time requirement of 30 frames-per-second (30 fps) for the algorithm.