Patent ID: 7683944

Claim:
A filter which filters original image data, said original image data having original luminance data and color difference data, comprising: a generating processor that generates first luminance data and second luminance data such that said original luminance data is separated into said first luminance data and said second luminance data according to a predetermined ratio, wherein said original image data undergoes a gamma correction using a first gamma curve so as to generate said first luminance data, and said original image data undergoes a second gamma correction using a second gamma curve so as to generate said second luminance data, said second gamma curve being different from said first gamma curve, wherein said second gamma curve is selected from a stepwise series of predetermined resolutions, and wherein said first gamma curve has a zero offset, and said second gamma curve has a non-zero offset; a filtering processor that filters said second luminance data by a low-pass filter so as to transform said second luminance data into third luminance data while the first luminance data and the color difference data are not low-pass filtered; and a synthesizing processor that synthesizes said first luminance data, said color difference data, and said third luminance data into synthesized image data, without synthesizing filtered color difference data, wherein the third luminance data defines a blurred luminance image and the synthesized image data comprises a soft focus image in which the color balance of the original image data is preserved, and wherein said second gamma curve is changed so as to change the extent of the soft focus of said soft focus image.