Slide identification for lecture movies by matching characters and images
Noriaki Ozawa, Hiroaki Takebe, Yutaka Katsuyama, Satoshi Naoi, Haruo Yokota · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2003
Slide identification is very important when creating e-Learning materials as it detects slides being changed during lecture movies. Simply detecting the change would not be enough for e-Learning purposes. Because, which slide is now displayed in the frame is also important for creating e-Learning materials. A matching technique combined with a presentation file containing answer information is very useful in identifying slides in a movie frame. We propose two methods for slide identification in this paper. The first is character-based, which uses the relationship between the character code and its coordinates. The other is image-based, which uses normalized correlation and dynamic programming. We used actual movies to evaluate the performance of these methods, both independently and in combination, and the experimental results revealed that they are very effective in identifying slides in lecture movies.