Member Body/National Committee
AS ISO/IEC 29794.4:2025
Clause/Subclause
6.2.5.2.
Paragraph/Figure/Table
No response
Type of Comment
General
Comments
In the norm it is stated that:
compute $q^{RVU}_{local}$ as the ratio of the width of ridges against valleys in $S'$.
This implies that the local variable $q_{local}^{RVU}$ is a scalar, whereas in the NFIQ2 code it is a vector of ratios. In the NIST code, as well as Olsen's code, this local vector is appended to a 'global' vector, which is subsequently averaged to get $q^{\mu}_{RVU}$.
The implication that $q_{local}^{RVU}$ is a scalar is reinforced by the fact that other local quality metrics are scalar values (e.g., $q_{local}^{OFL}$, $q_{local}^{OCL}$), which are averaged to obtain a global value.
You will get a different outcome compared to the norm if you compute the average of the local ratios to obtain a scalar $q_{local}^{RVU}$ and then compute the average of all the local $q_{local}^{RVU}$ to get $q_{RVU}^{\mu}$. As such, the norm should clarify that in this case, $q_{local}^{RVU}$ is a vector.
Proposed Change
Rewrite k) as follows:
Compute $q^{RVU}_{local, i}$ for each ridge–valley pair $i \in {1, \dots, N}$ as the ratio of ridge-width to valley-width.
Member Body/National Committee
AS ISO/IEC 29794.4:2025
Clause/Subclause
6.2.5.2.
Paragraph/Figure/Table
No response
Type of Comment
General
Comments
In the norm it is stated that:
This implies that the local variable$q_{local}^{RVU}$ is a scalar, whereas in the NFIQ2 code it is a vector of ratios. In the NIST code, as well as Olsen's code, this local vector is appended to a 'global' vector, which is subsequently averaged to get $q^{\mu}_{RVU}$ .
The implication that$q_{local}^{RVU}$ is a scalar is reinforced by the fact that other local quality metrics are scalar values (e.g., $q_{local}^{OFL}$ , $q_{local}^{OCL}$ ), which are averaged to obtain a global value.
You will get a different outcome compared to the norm if you compute the average of the local ratios to obtain a scalar$q_{local}^{RVU}$ and then compute the average of all the local $q_{local}^{RVU}$ to get $q_{RVU}^{\mu}$ . As such, the norm should clarify that in this case, $q_{local}^{RVU}$ is a vector.
Proposed Change
Rewrite k) as follows:
Compute$q^{RVU}_{local, i}$ for each ridge–valley pair $i \in {1, \dots, N}$ as the ratio of ridge-width to valley-width.