Abstract: The invention provides a softscaled frequency compensation function that allows the evaluation of a first quality measure indicating a global impact of all distortions in an audio transmission system, including linear frequency response distortions and second quality measure that only lakes into account the impact of linear frequency response distortions. The softscaled frequency compensation function is derived from a softscaled ratio between a time integrated output and a time integrated input power density functions. The first quality measure is derived from the difference loudness density function as function of time and frequency, using the frequency compensated input loudness density function and the gain compensated output loudness density function both as a function of time and frequency, in the same manner as carried out in ITU standard P.862.

Abstract: Measurement system and method for determining a quality indicator for end-to-end data transfer in a wireless data network (1). A data network analysis system (10) is connected to the wireless data network (1) for measuring at least one system performance indicator using a predefined data transfer specimen. The measurement system (10) is further equipped with processing means (2) which are arranged for deriving the quality indicator for at least one other data transfer type from the at least one performance indicator. The present system and method also allow to analyse the contributions to the quality indicator for determining underlying causes for bad performance.

Abstract: Method and system for measuring the transmission quality of an audio transmission system (10). Preprocessing means (12) are present for preprocessing of an input signal (X) and an output signal (Y) to obtain pitch power densities (PPXwIKss(j)” 1?PYwrR.ss(fin) for the respective signals. Compensation means (13, 14) are provided for compensation of linear frequency response and time varying gain. Calculation means (13, 14) are present for calculation of loudness densities (LX(I)n, LY(fi,,) from the compensated pitch power densities, and computation means (15, 16) are provided for computation of a score (Q) indicative of the transmission quality of the system (10) from the loudness densities. The compensation means (13, 14) comprise an iterative loop having at least three calculations of compensations, each calculation comprising one of a calculation of a compensation of linear frequency response and a calculation of a local power scaling factor.

Abstract: Method and system for measuring the transmission quality of an audio transmission system, an input signal (X) being entered into the system, resulting in an output signal (Y), output by the system, both signals, the input signal and the output signal, being mutually processed, the method comprising that the output signal and/or the input signal of the system under test are scaled in a way that small deviations of the power are compensated, while larger deviations are compensated partially, dependent on the power ratio. An artificial reference speech signal may be created, for which the noise levels as present in the original input speech signal are lowered by a scaling factor that depends on the local level of the noise in this input.

Abstract: A method of and an arrangement for obtaining quality indicators for an objective assessment of a degraded or output video signal (11) with respect to a reference or input video signal (10). The strength of edges or signal transitions (12; 13) in both the input and the output video signals (10; 11) are calculated (14) providing input and output edge signals (15; 16). By processing (19; 21, 22) the edge signals (15; 16) introduced edges (23) and omitted edges (24) in the output edge signal (16) are established. For each of the luminance and chrominance signals of a colour video signal first and second quality indicators are obtained from normalized values of the introduced edges (23) and the omitted edges (24), related to the output edge signal (23) and the input edge signal (24) normalized by first and second normalization factors, recorrelation of calculated MOS and observed MOS by human test persons reaches a value of above 0.9.