7 research outputs found

    Towards Practical Face Recognition System Employing Row-Based Distance Method In 2dpca Based Algorithms

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    Automatic face recognition has been a focus research topic in past few decades. This is due to the advantages of face recognition and the potential need for high security in commercial and law enforcement applications. However, due to nature of the face, it is subjected to several variations. Thus, finding a good face recognition system is still an active research field till today. Many approaches have been proposed to overcome the face variations. In the midst of these techniques, subspace methods are considered the most popular and powerful techniques. Among them, eigenface or Principal Component Analysis (PCA) method is considered as one of the most successful techniques in subspace methods. One of the most important extensions of PCA is Two-dimensional PCA (2DPCA). However, 2DPCA-based features are matrices rather than vectors as in PCA. Hence, different distance computation methods have been proposed to calculate the distance between the test feature matrix and the training feature matrices. All previous methods deal with the classification problem mathematically without any consideration between feature matrices and the face images. Besides, the system performance in practical applications relies on the number of eigenvectors chosen. As a solution to the above mentioned issues, four new distance methods have been proposed in this thesis, which are based on the rows of a feature matrix of 2DPCA-based algorithms. Through experiments, using eight face databases, their improvements compared to the previous distance methods are demonstrated

    The Performance of Cooperative MIMO Scheme under Slow Fading Channel based on Fountain Code

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    Nowadays, the video calling, video on demand (VOD) and more services are desired for users. These services generate large traffic which requires special techniques for transmission without outages or failure during transmission operation. Fountain Code is the newest method in the encoding theory and it is handle designed to large data. Besides, modern MIMO channel gives higher capacity than traditional channel (SISO channel). This paper looks out of the performance of Fountain Code on MIMO Scheme under Slow Fading Channel. The results show the performance is the best on MIMO (DF). In addition, the performance increases by increasing in the number of receiver antennas. Keywords: Fountain Code, Luby Transform, Cooperative MIMO, Slow Fading, Bit Error Rate, Decode and Forward (DF)

    An Outage Probability in Cooperative MIMO Under Slow Fading Channel

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    Slow fading channel one of the most important channels which appears widely in cellular mobile system. Although, it has several problems such as bad effects of fading which cause an attenuation to the signal. This paper presents a new scheme in cooperative communication system under slow fading channel to enhance and increase the quality of communication systems performance. This new scheme is called a cooperative multiple input–multiple output Antenna. The main idea of this scheme depends on transmitting multi copy of message via tow paths. Its' performance has compared with MIMO technique in term of outage probability. Thus, the negative effects of fading are mitigated and the outage probability is enhanced. Furthermore, the reliability in communication system under slow fading channel has improved

    An Image Steganography Algorithm for Hiding Data Based on HDWT, LZW and OPAP

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    Image steganography is the art of information hiding, which embeds a secret data into a cover image. However, high capacity of secret data and high quality of stego image are key issues in image steganography. In this paper, an image steganography technique based on Haar Discrete Wavelet Transform (HDWT), Lempel Ziv Welch (LZW) algorithm and Optimal Pixel Adjustment Process (OPAP) is proposed. The HDWT is used to increase the robustness of stego image against attacks. To increase the hidden capacity, LZW algorithm is performed on the secret message. The OPAP is then applied to reduce the embedding error between the cover image and stego image. The experimental results are evaluated by four standard images as covers, and with two types of secret messages. The results demonstrate high visual quality of stego image with large Hidden Capacity (HC) of secret data compared with recent technique
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