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The high-efficiency video coding (HEVC) standard for three-dimensional (3D) video, which is called 3D-HEVC, improves the compression efficiency for high resolution 3D video sequences. In this study, three coding time reduction algorithms, namely fast coding unit partition, fast prediction unit (PU) partition and search range reduction, are proposed for inter-prediction of 3D-HEVC by referring to the depth edge information. The pixels in one object should have the same motion characteristics. By detecting depth edge, we can easily classify the regional pixels if they are in the same object. Thus, in the encoding stage, the sizes of coding and PUs can be determined by the proposed fast coding unit partition and fast PU partition methods, respectively. Furthermore, the range of motion search can be effectively reduced by the proposed search range reduction method. Experimental results show that the proposed depth edge-based motion search algorithms can reduce the coding time of inter-prediction by up to 62% on average with negligible quality degradation.

For future 3D TV broadcasting systems and navigation applications, it is necessary to have accurate stereo matching which could precisely estimate depth map from two distanced cameras. In this paper, we first suggest a trinary cross color (TCC) census transform, which can help to achieve accurate disparity raw matching cost with low computational cost. The two-pass cost aggregation (TPCA) is formed to compute the aggregation cost, then the disparity map can be obtained by a range winner-take-all (RWTA) process and a white hole filling procedure. To further enhance the accuracy performance, a range left-right checking (RLRC) method is proposed to classify the results as correct, mismatched, or occluded pixels. Then, the image-based refinements for the mismatched and occluded pixels are proposed to refine the classified errors. Finally, the image-based cross voting and a median filter are employed to complete the fine depth estimation. Experimental results show that the proposed semi-global stereo matching system achieves considerably accurate disparity maps with reasonable computation cost.

Application of authentication protocol and key exchange scheme are major research issues in current internet, and entity identification (users or servers) accuracy and security are thereby safeguarded by various types of verification programs. Therefore, in the last 10 years, it was accompanied with productive discussions, but those discussions mainly focus on single issues, and because of the lack of security, there still existed improvements. The concept of zero-knowledge proofs is well suited for the identification and signing within network system, which has been widely used since proposed in 1985. However, common identification methods are only fit for individual user. In an increasingly complex network environment of today, information is usually conveyed through many unidentified servers, as a result, we have to encrypt messages by adopting different kinds of session keys. As for the chaotic maps technology, it also serves as a new encryption technology, widely adopted in communication protocols and key agreements over the years. As a consequence, in this study, we are going to propose an authentication protocol with key exchange function by taking advantage of characters of zero-knowledge proofs and chaotic maps, as well as adopt the BAN-logic to prove the security of this protocol. This study also compares the results of the security analysis of our protocol and related works. As a result, our proposed protocol has more security than others. owner of this secret message. And applications of zero-knowledge proofs may save the authenticator from conveying any secret message, which effectively prevents eavesdropping or replay attacks. Application scope of zero-knowledge proofs shall include user identification [16][17][18][19], electronic voting [20,21], digital cash [22,23], blind signature [24,25], and so on. In order to extend its application scope, Schnorr [19] had proposed an improved zero-knowledge proofs in the year 1989, which is perceived as a more effective verification method suitable for using smart cards.Since 1990s, chaotic system [18,[26][27][28][29][30] has been widely used in designing a secure communication protocol. And in the past 10 years, encryption system based on chaos theory has been studied extensively. Chaotic maps include the design of symmetric encryption protocol [31-34] and hashing function [35][36][37]. Lately, chaotic system is also applied in signature scheme [38].Traditional authentication protocols do not have key exchange function, or parts of authentication protocols have key exchange function, but because of the lack of security, for this purpose, we have proposed an enhancement authentication protocol with key exchange function applied in network system by making use of characters of zero-knowledge proofs and chaotic maps, and attached it with higher security, stronger anonymity, faster efficiency, and better integrity. Moreover, we have also adopted the BAN-logic to prove the security of this protocol. In chapter 2, we have first introduced some concepts related to z...

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