Now a days digital video is very popular as an exchange mediumdue to large improvement in video recording and compression techniques andincreasing of network-speed.
Therefore audiovisual recordings are used more frequentlyin e-learning and e-lecturing systems. OCR from videography is a technique thatcan locate any text inside a digital video file via reading and automatic extraction of any notes and captionsthat gives the actual information (like – the names of people, places ordescription of objects etc.) about the video being presented. Detecting the video-contentrequires many technologies like scanning, pre-processing, search strategies, videosegmentation, feature-extraction, recognition etc. Reading the extracted notesand captions gives more appropriate information to understand the video-content.Applying OCR on video and combining the results with various detecting techniquescan improve the detection result. Although integrated character recognition intext-based videos is needed greatly.
Thereare various research fields which concerncharacter recognition from videos. In character extraction from the video difficultiesare present due to different conditions of title, character size and complexbackgrounds. In video caption resolution of character is lower and thebackground complexity is more severe than in other research. The first problemis low resolution of the characters.
An image size is limitedby title, number of scan lines defined in the NTSC standard. Therefore, the resolutionof characters in the video-caption is insufficient to implement stable androbust OCR-Videography systems. Another problem is the presence of complex backgrounds.Characters superimposed on videos often have similar hue and brightness to thebackground. Presence of these problems in OCR-Videography systems has opened anew area for research work. OCR from videography is a technique that cangreatly help to locate the topics of interest in a large digital video via theautomatic extraction and reading of captions and notes.