Survey on Metric Rectification of Warped Document Images
نویسنده
چکیده
Metric rectification method is to restore an image from a single camera-captured document image. This method construct an isometric image mesh technique by exploiting the geometry of page surface and camera. It uses a general cylindrical surface (GCS) to model the curved page shape. It introduce a paraperspective projection to approximate the nonlinear perspective projection. A set of close-form formulas derived for the estimate of GCS directrix and document aspect ratio. This provides a straightforward method for image metric rectification. This paper focus on the survey of metric rectification established by different authors. Keywords—Document image analysis, image geometry, geometric restoration, mesh warping.
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