Research On Content Analysis And Feature Extraction Of Flash Animation

Flash animation,as an important form of multimedia presentation, is widely applied in teaching, which may be used in descripting the teaching content vividly and turning boring, difficult lessons into active, understandable ones, so it is helpful to solving the key and difficult points of teaching content and arousing the initiative, enthusiasm and creativity of students in study. However, with the increase of Flash resources, the sharing and using of Flash animation are restricted to their less effects of research engine based on texts, so it is essential to carry out many new researches as to how to find the teaching resources of Flash format in need efficiently and to make better use of them, such as the storing, cataloguing, indexing and realizing the effective access. Among them, one important research topic is how to retrieve Flash animations accurately, browse numeric Flash animations quickly, abtain and express the main content of the Flash animations in a proper way. Accordingly, the methods of content analysis and feature extraction are studied in order to provide some help for the accurate retrieval and quick browsing of Flash animations in this paper.The in-depth study is carried out on the technology of content analysis and feature extraction of Flash animations, according to the features of Flash animation and the analysis method based on content. The main jobs and innovation are as follows.1. The storage mechanisms, storage methods, compression method of Flash animation are analyzed according to the SWF File Storage Specification Version 8. And then the Flash animation structure analysis tool, the Flash animation protect removing tool and Flash animation decompression tool are powered by using Visual C++ 6.0.2. The four level feature extraction of Flash, their relationship, the main content of feature extraction and the method of feature extraction and presentation are presented according to the multimedia features, dynamic features, and interactive features of Flash animations. The jobs of this part are as follows: (1) The general requirements of feature extraction, the method of storage and extraction of Metadata, the features and presentation of multimedia object in Flash animation, the features of dynamic effects and the features of interactive events are analyzed and described.(2) The method of embedded text extraction in Flash animation is studied deeply, and the tool for text extraction is developed by using Visual C++ 6.0. The text extraction of static text, dynamic text and input text are realized according to the difference of text type, text encoding, storage format, the tags used by different text type and the function. And the processing of text segmentation and weighted sorting is implemented3. The concept of Flash Summarization is presented. The method of Flash Summarization based on visual features is proposed and the tool for Flash animation summary is developed through the analysis of Flash playing structure.(1) The sequence numbers of key frames are indexed by the method of tag matching through the analysis of the tags which are used by key frame and its order of arrangement. Then the images of key frames are obtained and saved through screenshot function of Flash Player ActiveX .(2) The color feature distance between two key frames is selected to describe the similarity of two key frames. And the distance is the basis of the scene segmentation. The scene images segmented from key frames are converted to looped GIF animations and formed the summarization of Flash animations. In this paper, two methods, the color histogram and the weighted average color of 9 blocks, are used to represent the color features, and good results are got in experiments.