Method and apparatus for automatically adjusting sharpening weighting value
View Patent ↗A method of automatically adjusting sharpening weighting value in an image sharpening process is disclosed. The method utilizes scanning a correction board having a black reference region, a white reference region and a plurality of line pair regions to aid the calculations of the modulation transfer function value and noise value. The method automatically adjusts weighting values of a sharpening function and avoids accompanying noise increase simultaneously in an image sharpening process performed in an image processing apparatus and thereby high quality images with high signal/noise ratio can be provided.
1. An article comprising: a storage medium having stored thereon instructions that, if executed, result in:
scanning a correction board having a black reference region, a white reference region and a line pair region;
calculating a modulation transfer function value using information generated by the scanning operation of the correction board and further using a weighting value;
comparing said calculated modulation transfer function value with a preset modulation transfer function specification; and
increasing the weighting value if the calculated modulation transfer function value is less than the preset modulation transfer function value.
2. The article of claim 1 , further comprising:
calculating a noise value by using information generated by the scanning operation of the correction board and further using the weighting value;
comparing said calculated noise value with a preset noise specification; and
decreasing the weighting value if the calculated noise value exceeds the preset noise specification.
3. A correction board, comprising:
a black reference region;
a white reference region wherein the black and white reference regions are capable of being scanned to generate noise values for use in adjusting a weighting value for image sharpening; and
a plurality of line pair regions capable of being scanned to generate a modulation transfer function value.
4. The correction board of claim 3 , wherein at least one of the plurality of line pair regions includes at least two substantially parallel substantially black lines and a substantially white region between said substantially parallel substantially black lines.