GstPEAQ - A GStreamer plugin for Perceptual Evaluation of Audio Quality

GstPEAQ is an implementation of the algorithm described in "Recommendation ITU-R BS.1387-1: Method for objective measurements of perceived audio quality", both in its basic and advanced version. It does not, however, conform to ITU-R BS.1387-1 in the sense that is does not compute values within the allowed tolerance for the given test items. The implemented algorithm of ITU-R BS.1387-1 provides a way to compute an impairment grade between a reference audio signal and a test audio signal, being the reference signal after having undergone some distortion like e.g. perceptual coding. The impairment is measured in terms of the Objective Difference Grade (ODG) that should match the rating of an average human expert listener on a continuous scale with the following anchor points: 0 - impairment imperceptible -1 - impairment perceptible but not annoying -2 - impairment slightly annoying -3 - impairment annoying -4 - impairment very annoying Although GstPEAQ does not conform to ITU-R BS.1387-1, deviations are sufficiently small such that it should still provide an alternative to listening tests just as good as implementations conforming to ITU-R BS.1387-1 do. See M. Holters and U. Zölzer, "GstPEAQ – an Open Source Implementation of the PEAQ Algorithm" (http://www.hsu-hh.de/download-1.5.1.php?brick_id=gywLUdLoxvNqEvNJ) for details.

GstPEAQ comes as a GStreamer plugin providing an element named "peaq". The element has two sink pads, "ref" and "test" for reference and test signal, respectively. The computed ODG can be obtained by reading the "odg" property. For the common case that reference and test signal are available as WAV files (or in another format readable by GStreamer), a command line utility "peaq" is provided that can simply be invoked as peaq [--advanced] {REFFILE} {TESTFILE} where --advanced chooses the advanced version of the algorithm (the basic version is used by default), and {REFFILE} and {TESTFILE} give the reference and test signal file name, respectively.

Although development is primarily done for the Linux platform, GstPEAQ has been successfully compiled for Windows and Mac OS X, too. See the respective INSTALL.* file for further information.

Reference documentation, both concerning invocation and internals, can be found at doc/html/index.html.