HTable property (Main Control)

Visual Basic example
Visual C++ 4.0 example

Syntax short HTable (short iIndex);

Overview:  Refer to Changing Brightness and Contrast.

Remarks

Hue lookup table. This is one of the four tables that the RemapHue method uses to change the bitmap's hue, saturation and value. This property is used only if the bUseHTable parameter is set to TRUE when the RemapHue method is called. Hue, Saturation, and Value levels range from 0 to 255. Therefore, the lookup tables each have 256 entries. The current hue, saturation and value of a pixel correspond to the table indexes. If the bUseMaskTable parameter is set to TRUE when the RemapHue method is called and the MaskTable(i) entry for a particular hue is not zero, then the hue is changed to the hue in HTable(i). If MaskTable(i) is 0 then HTable(i) is ignored. For example, if RemapHue is called with both bUseMaskTable and bUseHTable set to TRUE, then if a pixel has a hue of 85 and the MaskTable(85) is not 0, the hue of the pixel is changed to HTable(85).

Traditionally, hue ranges from 0 to 359. For the lookup table, the range of 0 to 359 is remapped to a range of 0..255. For example,

 

Color

Hue(0..359)

Hue(0..255)

Red

0

0

Green

120

85

Blue

240

170

See Also

Elements:  RemapHue method, MaskTable property, STable property, VTable property, HSV_HfromRGB method, HSV_SfromRGB method, HSV_VfromRGB method, RGBfromHSV method

Topics:  Raster Images: Modifying Intensity Values