Binarization of Textual Content in Video Frames

In this paper we present a binarization technique for textual content in video frames which can be applied in the resulting image of the text detection step aiming in an improved OCR performance. The proposed technique is based on the detection of the text baselines in order to define the main body of the text. The main body of the text is used to detect the stroke width of the characters which will address the two consecutive locally adaptive binarization steps that follow. At the first step, we use different valuation in parameters for the inside and outside area of the main body of the text. To include the thinned or broken binarized parts that may exist outside the main text body, convex hull analysis is performed so that the entire text body is considered. At the second step, binarization is performed with different valuation in parameters for the inside and outside area of the entire text body. The effectiveness of the proposed technique is demonstrated by both qualitative and OCR-based evaluation.