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.