已知定义在\(R\)上的函数\(f\left( x \right)={{2}^{\left| x-m \right|}}-1\left( m\in R \right)\)为偶函数，记\(a=f\left( -2 \right),b=f\left( {{\log }_{2}}5 \right)\)，\(c=f(2m),则a,b,c \)的大小关系为