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Chaotic Arithmetic Coding for Secure Video Multicast  [PDF]
Gaurav Pande
Computer Science , 2013,
Abstract: Arithmetic Coding (AC) is widely used for the entropy coding of text and video data. It involves recursive partitioning of the range [0,1) in accordance with the relative probabilities of occurrence of the input symbols. A data (image or video) encryption scheme based on arithmetic coding called as Chaotic Arithmetic Coding (CAC) has been presented in previous works. In CAC, a large number of chaotic maps can be used to perform coding, each achieving Shannon optimal compression performance. The exact choice of map is governed by a key. CAC has the effect of scrambling the intervals without making any changes to the width of interval in which the codeword must lie, thereby allowing encryption without sacrificing any coding efficiency. In this paper, we use a redundancy in CAC procedure for secure multicast of videos where multiple users are distributed with different keys to decode same encrypted file. By encrypting once, we can generate multiple keys, either of which can be used to decrypt the encoded file. This is very suitable for video distribution over Internet where a single video can be distributed to multiple clients in a privacy preserving manner.
An efficient coding algorithm for stereo video with 3D-SPIHT

Zhang Yongdong,Li Gulling,

电子与信息学报 , 2002,
Abstract: This paper presents a new strategy for efficiently coding stereo video sequences. In the scheme, the auxiliary sequence is coded by disparity compensated prediction and 3D-SPIHT algorithm. 3D-SPIHT algorithm is based on genuine 3D wavelet transform, and implements a three dimensional extension of SPIHT in still image coding by defining a new spatio-temporal orientation tree structure. The scheme can provide comparable performance to the conventional method with minimal computational complexity and produce an embedded bit stream in the auxiliary sequence. According to channel bandwidth, the bit rate can be adaptively adjusted so that the best quality of the auxiliary sequence is obtained.
A Pixel Domain Video Coding based on Turbo code and Arithmetic code  [PDF]
Cyrine Lahsini,Sonia Zaibi,Ramesh pyndiah,Ammar Bouallegue
International Journal of Wireless & Mobile Networks , 2012,
Abstract: In recent years, with emerging applications such as multimedia sensors networks, wirelesslow-power surveillance and mobile camera phones, the traditional video coding architecture in beingchallenged. In fact, these applications have different requirements than those of the broadcast videodelivery systems: a low power consumption at the encoder side is essential.In this context, we propose a pixel-domain video coding scheme which fits well in these senarios.In this system, both the arithmetic and turbo codes are used to encode the video sequence's frames.Simulations results show significant gains over Pixel-domain Wyner-Ziv video codeingr.
Design and Implementation of Arithmetic Coder Used in SPIHT
K.Harika,Asst.Prof K.V.Ramana Reddy
International Journal of Innovative Technology and Exploring Engineering , 2013,
Abstract: In this paper Set Partitioning in Hierarchical Trees (SPIHT) algorithm for image compression is proposed with a arithmetic coder thereby it compresses the Discrete Wavelet Transform decomposed images. This architecture is advantageous from various optimizations performed at different levels of arithmetic coding from higher algorithm abstraction to lower circuit implementation. SPIHT has straightforward coding procedure and requires no tables which make a SPIHT algorithm an appropriate one for low cost hardware implementation. In order to avoid rescanning the wavelet transformed coefficients a breadth first search SPIHT without lists is used instead of SPIHT with lists. With the help of Breadth First search high speed architecture is achieved. Dedicated circuit such as common bit detector is used for loop unrolling the renormalization stage of arithmetic coding. Critical path in the architecture are shortened by employing Floating point multiplier and carry look ahead adder. Design has been implemented on Spartan 6 FPGA.
Improvement of SPIHT algorithm based on lifting scheme

CHEN Hong-xin,LIU Zheng-guang,ZHANG Hong-wei,YANG Zheng-ling,

计算机应用 , 2006,
Abstract: Due to the computational complexity of SPIHT, the integer-to-integer lifting scheme, which could simplify the computational process, was adopted instead of the normal wavelet transform. Wavelet coefficients were divided into blocks, based on which the spatial orientation trees were re-organized. The context-based model was constructed according to the correlativity of neighboring coefficients in blocks, and the outputting signals were encoded by adaptive arithmetic code to improve coding efficiency. Experiments show that the PSNR value is more than that of the original SPIHT at the same bit rate.
Study of CAC-based Secure Coding of Digital Video

WANG Yin-miao,BAO Xian-yu,

中国图象图形学报 , 2010,
Abstract: based adaptive coding (CAC) is a class of new high-efficient entropy coding techniques for video compression. In this paper, a CAC-based scheme is presented to achieve realtime secure coding for digital video, and a secure coding chain is built based on CAC secure coder. Two kinds of secure coding operations, including context-based adaptive binary arithmetic secure coding (CABASC) and context-based adaptive variable length secure coding (CAVLSC), are given. The experimental results show that this scheme has significant improvement on security, real-time performance and flexibility of software implementation. These properties make it a sound foundation for further research on CAC secure coding.
Motion Compensated Video Compression with 3D Wavelet Transform and SPIHT
B. Enyedi,L. Konyha,K. Fazekas
Radioengineering , 2006,
Abstract: The following paper introduces a low bitrate video coding method on the basis of 3D motion compensated wavelet transform and SPIHT algorithm. In contrast to the conventional algorithms applying motion compensation and differential coding, here wavelet transform is used to exploit the opportunities of time redundancy. For coefficient collection, the 3D version of SPIHT algorithm was selected from the various procedures developed for wavelet transform. Motion vectors are compressed, too (also by wavelet transform), therefore the time and spatial redundancy of coding is exploited here as well. These procedures result in effective video compressing and can easily be aligned to the MPEG4 standard.
SPIHT: Highly Efficient Technique for Image Transmission and Coding
Chopade Nilkanth,Ghatol A
IETE Technical Review , 2008,
Abstract: Uncompressed multimedia data (graphics, audio and video) requires considerable storage and transmission bandwidth. A fundamental goal of data compression is to reduce the bit rate for transmission or storage while maintaining acceptable quality. Image coding and compression technique, converts an image that requires low memory storages space, smaller bandwidth for transmission, high PSNR with acceptable image quality. This paper presents wavelet based coding algorithm SPIHT to encode and compress an image data. The coding and decoding process is comparatively fast. The numerical results obtained using MATLAB shows that the output image has high value of PSNR with good compression ratio for low bit rate.
Wavelet Image Coding by Dilation-Run Algorithm

Wu Zheng,He Ming-yi,

电子与信息学报 , 2005,
Abstract: A novel wavelet image coder based on morphological dilation and run-length coding, dilation-run algorithm, is proposed according to both intra-subband clustering of signiflcant wavelet coefflcients and inter-subband dependency in significant fields. The algorithm mainly involves discrete wavelet transform, bit-plane coding, morphological dilation of signiflcant coefficient cluster within subbands, coefficient's significance predicting across subbands, run-length coding of the insignificant coefficients before each seed and adaptive arithmetic coding. The two key features of the algorithm are morphological dilation and run-length coding. The morphological dilation operator is used to search and encode the significant coefficients in each cluster, while a new run-length coding method is used to encode the position of the seed of each cluster, which is the start pixel of the dilation. The dilation-run algorithm, as a kind of embedded coder, is also rate scalable. The experimental results show that the new coder outperforms the zerotree coder SPIHT and is competitive with the morphology coder MRWD and SLCCA. For images with strong clustering feature after the wavelet transform, the new coder outperforms both the morphology coders above.
Improved ROI image coding based on SPIHT

LUO Ming-feng,TENG Qi-zhi,HE Xiao-hai,

计算机应用 , 2006,
Abstract: There are two ROI(region of interest) coding methods in JPEG2000: max shift and scaling-based shift method, which can reconstruct ROI at frist. SPIHT, a very efficient embedded zerotree wavelet coding, was adapted in ROI coding. The frist n high bit planes were encoded in no difference between ROI and backgroud. The rest bit planes were encoded with zero for backgroud, but SPIHT for ROI. The merit of this method is that the number of bit planes is reduced and the base information of whole image is rebuilt at first. The image can be decoded applying original SPIHT decoding program. This method can be used in the existing SPIHT method and rebuilt ROI.
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