Image inversion mode.

Values:

IG_REC_IMG_INVERT_NO	No inversion required.
IG_REC_IMG_INVERT_YES	Image inversion should be performed.
IG_REC_IMG_INVERT_AUTO	Automatically inverts the image, if necessary (Default): whether the image is inverse is determined during preprocessing.

Remarks:

Possible inversion modes. This setting determines the inversion mode used by IG_REC_image_preprocess on the whole image. For B/W images, the usual inversion is from white-on-black to black-on-white, because it is the latter that is needed for successful recognition. In grayscale images, each pixel value is transformed to its complementary value. In color images, each color component is inverted to its complementary value.