Offset Cross-Star Correction Method Based on Color Image Registration
Mei Wang · China Printing and Packaging Study · 2012
Offset cross - star correction method based on color image registration was proposed to solve the four - color registration problem of large -scale offset press.Using the method,firstly,the monochromatic images(C、M、Y、K) were extracted respectively from CCD image depending on color feature.And the cross - star positions of each color were detected respectively from the monochromatic images.Then the tilt and shift correction parameters of each color cross - star were computed using the vertical and horizontal projection distance of the binary monochromatic images in order to achieve the offset press mechanical correction.In this paper,four-color cross -star registration was completed using affine transformation. And the final registration result was tested by overprinting four color registration images together.The experimental result showed that using the color and grayscale features of the original image to regulate image,the offset press registration method is precise and easy to achieve.