Fig. 9

The Facial geometric indicators(FGI) value of Tangka Buddhist statues over the 11–19 century, a–i correspond to the 11th–19th centuries respectively, the facial geometric indices A-P (X-axis) are codes of FGI in Table 2, the FGI value (Y-axis) is measured value of indices A-P, each colored line represents the FGI measurement result of a corresponding Buddha face sample