The Research And Application On Adaptation Model Of Micro-course Video Resources

With the development of the internet and mobile technology,a variety of terminal equipment and complex heterogeneous networks have also posing new challenges to multimedia technology. And video resources appear in large number as the main forms to bear knowledge with the popularity of mirco-course. Learner will use a number of different devices when they use micro-course video. The diversity of terminal requires video streams with different resolution, bitrate, etc. The adaptation technology for micro-course video has been a new research hotspot as an effective way to solve this problem. But the current video adaptation researches focus on the coding efficiency of video. The video must be adapted before displayed in the terminal in order to arrange the compute and storage resources with the least waste. Adaptive transmission and adaptation for micro-course video depending on terminal conditions can optimize the uses’ vision on subjective quality, it can also save the compute and storage resources.In order to meet the need that the micro-course video resources are access to learners anytime and anywhere, this paper proposed a new model for the adaptation of micro-course video resources, designed a description model of micro-course video resource and improved the adaptation process. Firstly, based on the MPEG-21 framework,a new model for the adaptation of micro-course video resources is proposed. The model is divided into three parts: Description Adaptation Engine,Adaptation Decision-Taking Engine, Bitstream Adaptation Engine. Rule-based adaptation strategy is selected in Adaptation Decision-Taking Engine which is used in many models. Adaptation Decision-Taking Engine will send the decision-making parameters to the Description Adaptation Engine and Bitstream Adaptation Engine. A description model of micro-course video resource is studied in Description Adaptation Engine which is based on the MPEG-7 and CELTS-41 standard. Then, transcoding sequence planning algorithm is designed. The adaptation operation process of micro-course video resources can be regarded as a sequence from the original state to the final state. Get all transcoding sequences using the method of exhaustion, and compute the time of every transcoding sequence with the atomicity operations which are stored in the BitStream Adaptation Engine. Take the sequence which will spend shortest time as the most optimal adaptation Path. After many tests, some general adaptation operation sequences are summarized.And improve the original algorithm regarding these sequences as heuristic rules. The improved algorithm shall be the final algorithm. Finally, with the proposed adaptation model as the core, this study designs and implements a micro-course video adaptation prototype system. In addition, this study selects the adaptation time as indicator to evaluate the proposed transcoding sequence planning algorithm. The experiments show that this transcoding sequence planning algorithm can improve the reusability and efficiency of adaptation operation and the micro-course video adaptation prototype system has higher user satisfaction.Taking the micro-course video as the study subject, it not only provides a new idea for the adaptation of micro-course video resource, but also provides a new method for the adaptation of resources which are in other types to explore the description and the optimization of the adaptation of the micro-course video resources.