ImageGear for C and C++ on Windows v19.10 - Updated
enumTIFFBitonalPaletteMode
API Reference Guide > Core Component API Reference > Core Component Enumerations Reference > enumTIFFBitonalPaletteMode

This enumeration specifies whether ImageGear shall fix strange looking palettes when reading bi-tonal TIFF images.

Values:

IG_TIF_BITONAL_PALETTE_MODE_LEGACY Keep ImageGear 16.0 behavior: read all 1-bit palettes as is; if palette is missing, assume increasing (blackzero) palette.
IG_TIF_BITONAL_PALETTE_MODE_KEEP_AS_IS Keep palette as is, even if it is all-black or red-green. If photometric interpretation is PALETTE_COLOR, but COLORMAP tag is absent, assume all-black palette.
IG_TIF_BITONAL_PALETTE_MODE_FIX Fix strange looking palettes, as follows: if (R0+G0+B0)/3 < (R1+G1+B1)/3 change palette to (black, white). Otherwise, change palette to (white, black). Specifically, constant palettes (all-black, all-white) are replaced with (white, black) palette.