Function norm2 

pub fn norm2(
    src1: &impl ToInputArray,
    src2: &impl ToInputArray,
    norm_type: i32,
    mask: &impl ToInputArray,
) -> Result<f64>

Calculates an absolute difference norm or a relative difference norm.

This version of cv::norm calculates the absolute difference norm or the relative difference norm of arrays src1 and src2. The type of norm to calculate is specified using #NormTypes.

Parameters

• src1: first input array.
• src2: second input array of the same size and the same type as src1.
• normType: type of the norm (see #NormTypes).
• mask: optional operation mask; it must have the same size as src1 and CV_8UC1 type.

C++ default parameters

• norm_type: NORM_L2
• mask: noArray()