Research Article

A Novel Two-Stage Illumination Estimation Framework for Expression Recognition

Table 4

Estimation accuracy by computing the relative horizontal angles for different flashes. Camera numbers are 5, 27, and 34. Illumination numbers are 9, 11, and 21. The last column (computed values) is calculated from geometric information provided in the database.

Average estimationStandard deviationComputed values

Illumination: 8.46°/10.28°34.52°/20.04°16.53°
Illumination: 2.12°/1.89°7.28°/5.63°4.30°