DOC2_CONVERSIONMODE

typedef enum 
{ 
   DOC2_CONVERSION_AUTO = 0, 
   DOC2_CONVERSION_SET, 
   DOC2_CONVERSION_NO, 
   DOC2_CONVERSION_GLOBAL, 
   DOC2_CONVERSION_GRAY, 
} DOC2_CONVERSIONMODE;

The DOC2_CONVERSIONMODE enumeration specifies how a non-B/W image, which is stored in the engine, will be converted to a B/W image.

Value	Meaning
DOC2_CONVERSION_AUTO	This affects grayscale or 24-bit color images. A B/W image will be created in the engine's memory. Image binarization applies an automatic adaptive thresholding algorithm. The nBrightness member of the DOC2PREPROCESSINGOPTIONS structure can be used to tune the threshold calculation.
DOC2_CONVERSION_SET	This affects grayscale or 24-bit color images. A B/W image will be created in the engine's memory. Thresholding with a user-defined threshold value, is set by the nThreshold member of the DOC2PREPROCESSINGOPTIONS structure.
DOC2_CONVERSION_NO	There will be no conversion while image loading. The image will be loaded into the engine's memory without any conversion (i.e. a color image will retain its color attributes).
DOC2_CONVERSION_GLOBAL	This affects grayscale or 24-bit color images. A B/W image will be created in the engine's memory. For image binarization, an automatic thresholding algorithm with a page-level global threshold value is applied.
DOC2_CONVERSION_GRAY	For a color image, a grayscale image will be created in the engine's memory. For a B/W or grayscale image, no conversion will be performed while loading the image.