An effective trajectory-based algorithm for ball detection and tracking with application to the analysis of broadcast sports video

Ph.DDOCTOR OF PHILOSOPH

Automatic Identification of Text In Digital Video Key Frames

Scene and graphic text can provide important supplemental index information in video sequences. In this paper we address the problem automatically identifying text regions in digital video key frames. The text contained in video frames is typically very noisy because it is aliased and/or digitized at a much lower resolution than typical document images, making identification, extraction and recognition difficult. The proposed method is based on the use of a hybrid wavelet/neural network segmenter on a series of overlapping small windows to classify regions which contain text. To detect text over a wide range of font sizes, the method is applied to a pyramid of images and the regions identified at each level are integrated. 1. Introduction The increasing availability of online digital imagery and video has rekindled interest in the problems of how to index multimedia information sources automatically and how to browse and manipulate them efficiently. Traditionally, images and video seq..

Scene text area detection from video

Text detection from videos is a well known research area. Especially the detection of static superimposed text such as captions has been researched successfully, but makes many assumptions that question the applicability of those algorithms for moving scene text. In this dissertation, I propose a scene text area detection approach that includes a simple key frame extraction, feature extraction, feature code generation and text area classification. Common edge and variance based features of scene text areas are evaluated and comprised in a "combined feature scheme". For the detection of text areas, two classifiers using a self-organising map and a feed-forward neural network are compared. Ground truth video data with different characteristics is used to compare the neural computing methods. 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