| 摘要 |
A method for obtaining and/or enhancing local contrast differences (LD) in digital image input data (in), wherein a local contrast measure (SADap) approximating a two- dimensional sum of absolute difference (SAD) measure is obtained by obtaining a first- dimension sum of absolute difference measure (energyVk(m, n)) representing a sum of absolute difference (SAD) in a first dimension of at least one image region, and obtaining the local contrast measure (SADap) as a second-dimension convoluted first-dimension sum of absolute difference measure by convo luting the first-dimension sum of absolute difference measure (energyVk(m, n)) in a second dimension of the at least one image region, is proposed, wherein the step of obtaining the local contrast measure (SADap) as the second-dimension convoluted first-dimension sum of absolute differences measure further includes an addition step wherein an energy term (?lpfk(j)) representing a first- order difference on a distance (J) of a low pass filtered signal used in obtaining the first- dimension sum of absolute differences measure (energyVk(m, n)) and in obtaining the second-dimension convoluted first-dimension sum of absolute differences measure is introduced while obtaining the local contrast measure (SADap). |
