Expression of QoS in distributed multimedia applications is different from level to level. Therefore QoS mapping mechanisms, which translate the QoS expression from level to level, is required. In this report, a scheme to compose continuous QoS mapping functions from several discrete sample data is proposed in order to accept any QoS requirement from end-users. The mapping functions are specified by spline functions; especially B-splines are appropriate and useful to compose the mapping functions. Next, a method to measure the QoS mapping data automatically is proposed. The method is useful to mitigate tedious work of data measurement. The proposed automatic measurement method has been implemented in real PC and the experimental results of measurement are presented in this report.