Slant Correction Method for Banknote Image Based on Sobel Operator and Rotation Projection

Banknote image slant will seriously affect accuracy of character recognition.So,banknote image slant correction need to be done before character recognition.Sobel operator and rotation projection are used to correct slant banknote image.Firstly Sobel operator and rotation projection are used to get inclination angle of banknote image,and then bilinear interpolation is emplazed to carry out level rotation correction and vertical displacement deviation correction.At the same time,considering the actual situation and the real-time of correction,level angle and vertical angle are not more than 10 are defined.From the experimental results that correction effect is more obvious can be seen.