“…However, the symptoms on the tongue are very difficult to automatically identify or quantify, which has become a core challenge in SD. In recent years, many studies in this area have paid much attention to using deep learning methods to automatically classify or identify tongue symptoms, like tooth-marked tongue, 11 , 15 , 103 – 105 , 110 , 111 tongue coating, 10 , 16 , 31 , 42 , 112 , 113 coating color, 66 , 113 , 114 tongue color, 22 , 113 , 115 cracked tongue, 9 , 110 , 111 , 116 , 117 sublingual vein, 10 and fungiform papillae on tongue. 118 …”