| The New Media transmittd from everybody to everybody is different from the traditional media, which key characters are interactivity and equlity. In the traditional video services system, such as broadcast TV, the video can only be transmitted unidirectionally and received passively. While the rising New Media video service system especially for Ditigal TV sevice system which is most close to our life and gain wide popularity brought VCR functionality into online video service which can provides clients with individuation and is helpful for the develop of value-added service, thus accelerating system extention.In this paper, we mainly discuss about the interactivity of Digital TV video service system, including the support of VCR and the proposition of new service on interactivity. The main contributes of this paper are issulated as follows:1. We propose a new VCR supporting method which selects frames based on GOP and uses Variable Frame Rate(VBR). Selecting frames based on GOP can efficiently elimate the transmission of depended frames. With the traditional VCR supporting method, the frame rate is very high at fast forward and backward mode, thus unsuitable for transmission over internet. In our proposed method, the frame rate is controllable and adjustable thus leading to adjustable bit rate, with which the bit rate of fast forward/backward can be adaptive. The experimental results show that the proposed strategy can greately decrease the transmission rate of fast forward/backward, to 22%of that of normal playback at least.2. With the utilization of system hardware clock and low pass filtering, we propose a high precise traffic shaping method designed for large sacle concurrent playback. The haredward clock RTC is with high precision, however there can be on RTC used in system. We adopt a framework with multiple Token Bucket to generate multiple Token Bucket signal sources with the same precision as RTC, then these multiple Token Bucket signal soureces can privde high precision clock for the following low pass filtering stadge which would shape the traffic and control the packet transmission interval of each stream in th precision of lms. In the following Leacky Bucket based low pass filtering stage, the upper and lower bound of FIFO are set to automatily control the degree of wave crest descreased while the max delay of stream can be under control.3. We enhance the multi-view video system with VCR functionality. The multi-view video service system proposed nowadays can not support VCR functionality yet. The key issue at capture stage is to make the multi-view video streams captured be aligned. We ensure that the streams are aligned with globe time synchronizing and synchronization startup of the system. Compared with the expensive hardware based GENLOCK envirement, our scheme is a low cost replacement.4. Several application of New Media technology were studied and resolved, including:â‘ Support of VCR functionality with encrypted digital TV programs.â‘¡Support of VCR functionality with Flash.â‘¢Implementation of interactive advertisement in digital TV system.â‘£Design and development of interactive simulation software.Part of the above research results have been successfully appied to several projects, such as:Interactive TV Business and Supporting Platform in QingDao Cable Broadband Digital TV Corp, Interactive TV Integrated Services System in JiaDing of ShangHai, and SARFT HaiNan Cable TV Development on Bidirectional Service Application Test System and Terminate in HaiKou.
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