Grayscale Standard Dispaly Function | GSDF

To accomodate for changes in in light output (luminance) of a diagnostic or clinical grade monitor, input values are squeezed into fewer luminance output steps in the black area, while in the white area, they are stretched. We call this method perceptual linearization. This curve is documented in Part 14 of the standard, both as a look-up table specifying for each input value the corresponding output value in luminance, as well as in a mathematical form. It is called the Grayscale Standard Display Function (GSDF). All new to-be-defined DICOM objects require that when applying the pixel pipeline the information is represented in this device independent domain, and the GSDF can be applied to provide consistency. The outputs of this pipeline and the input of the GSDF curve are called presentation values or P Values