Table 2. Tongue segmentation threshold table.

Tongue category	H̅	S̅
Red Tongue	<17	0.40~0.65
Yellow Tongue	17~135	0.25~0.45
Purple Tongue	135~240	0.10~0.35
White Tongue	H>=240	0.07~0.20
Light Red Tongue	H>=240	0.20~0.40