3 Image Enhancement 3.3.1 Histogram Equalization (HE) >The constraints of HE Let re[0,L-1]be the input intensity,s=T(r)is the transformed intensity.It is required that the function T satisfies: 1) T(r)is a monotonically increasing function in the interval 0sr<L-1. 2) 0sTr≤L-1for0srs4-l, 第3章第7页3 Image Enhancement 第3章 第7页 3.3.1 Histogram Equalization (HE) The constraints of HE Let r[0,L-1] be the input intensity, s=T(r) is the transformed intensity. It is required that the function T satisfies: 1) T(r) is a monotonically increasing function in the interval 0rL-1. 2) 0T(r) L-1 for 0rL-1, 0 1 0 1 1 r r s r s s