Patent ID: 8588549
Filing Date: 2013-11-19
Classification: H04N

Abstract:
1. A de-skew method of an image forming apparatus, the de-skew method comprising: reading an image on a print medium fed through an automatic document feeder (ADF); detecting a leading edge of the print medium and calculating a skew angle of the read image, the leading edge representing a region between a blank space outside the print medium and edges of the print medium; comparing the calculated skew angle to a first threshold; and setting skew compensation levels based on the calculated skew angle and performing different de-skew operations according to the set skew compensation levels to output a de-skewed image when an absolute value of the calculated skew angle is equal to or greater than the first threshold, wherein the de-skew method further comprises outputting the image without performing the de-skew operation when the absolute value of the calculated skew angle is less than the first threshold, and wherein the outputting of the de-skewed image comprises de-skewing the image using a second threshold to output a de-skewed image when the absolute value of the calculated skew angle exceeds the second threshold, and de-skewing the image using an intermediate value between the first threshold and the second threshold to output a de-skewed image when the absolute value of the calculated skew angle is the intermediate value.