Convention Paper
True Peak Metering—A Tutorial Review
AES Convention 136 · Paper 9041 · April 2014
Abstract
Along with the loudness algorithm, ITU-R Recommendation BS.1770 specifies a true-peak metering method using oversampling and interpolation. The need for such metering is discussed, along with considerations on its implementation and on its usage. Implementation issues include oversampling factor, the tradeoff between accuracy and processor load and the proportion of total processor load when combined with loudness measurement. Four sources of error are examined: timing of interpolated samples, ripple in the passband response of the interpolation filter, incomplete alias suppression in the stopband response of the filter and departure from linear phase response. Implications of filter topology and filter order are discussed. An example of implementation is given along with performance parameters.
