| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique for adjusting the dynamic range of an imaging system (10). SOLUTION: This technique includes balancing of pure gray level processing with pure frequency processing to reduce the brightness of light regions in an image and to maintain contract in darker regions. The technique applies unsharp masking in which a set of parameter values are used based upon smoothed pixel values for an image. The unsharp masking parameters (96, 98, and 100) may be substantially zero below a threshold and increase nonlinearly above the threshold. A set of brightness control parameters (124 and 128) are then used to adjust an output value for each pixel to a desired dynamic range. The brightness control parameters may also be nonlinear. |
