Levels effect parameter structure
Global Const $tagGDIP_EFFECTPARAMS_Levels = "int Highlight; int Midtone; int Shadow"
| Highlight | Integer in the range 0 through 100 that specifies which pixels should be lightened. |
| Midtone | Integer in the range -100 through 100 that specifies how much to lighten or darken an image. |
| Shadow | Integer in the range 0 through 100 that specifies which pixels should be darkened. |