关键词: 文档图像, 倾斜检测, 投影, 栅缝, 优化

Abstract: Skew document images often appears when it is captured by image acquisition devices such as cameras or scanners, which may induce recognition mistakes by Optical Character Recognition (OCR) software. The paper proposed an optimized method for the skew detection of document images, and its objective function is the image projection grating slit width. The document image angle is the inverse of the projection angle, when the corresponding projection grating slit width is the largest. The detection range is expanded and the detection speed is increased by the grating line width function. The amount of calculation in detection is decreased by preliminary projection on equispaced rows and back projection. The detection precision is improved by dichotomy. In the experiments document images where a few illustrations were used, and the skew detection results show the proposed method is of high efficiency and robustness.

Key words: document image, skew detection, projection, grating slit, optimization