1、 1 - Place des Nations Telephone +41 22 730 51 11 Telex 421 000 uit ch E-mail: itumailitu.int CH-1211 Geneva 20 Telefax Gr3: +41 22 733 72 56 Telegram ITU GENEVE www.itu.int Switzerland Gr4: +41 22 730 65 00 QUESTION ITU-R 122/6 Objective perceptual audio quality measurement methods (2006) The ITU
2、Radiocommunication Assembly, considering a) that conventional objective measurement methods (e.g. for measuring signal-to-noise ratio and distortion) may no longer be adequate in assessing systems which use low bit-rate coding schemes or which employ analogue or digital signal processing; b) that lo
3、w bit-rate coding schemes are rapidly being deployed both at intermediate audio quality levels, which is corresponding to be equivalent to or better than a good reception of FM or AM analogue broadcasting services, and in multichannel configurations; c) that not all implementations conforming to a s
4、pecification or standard guarantee the best quality achievable within that specification or standard; d) that formal subjective assessment methods are not always suitable for the monitoring of audio quality under operational conditions; e) that objective perceptual measurement methods may eventually
5、 complement or supersede conventional objective measurement methods in all areas of measurements; f) that Recommendation ITU-R BS.1116 is focusing on the subjective measurement of audio signals for high-quality audio in mono, stereo and multichannel configurations; g) that Recommendation ITU-R BS:15
6、34 is recommended for the subjective assessment of audio quality at intermediate audio quality; h) that Recommendation ITU-R BS.1387 was validated with subjective data derived with Recommendation ITU-R BS.1116 only, and is focusing on the objective measurement of mono and stereo signals at high-qual
7、ity audio only; j) that several broadcasters have already introduced or planned digital broadcasting services whose audio quality is at intermediate quality as defined in Recommendation ITU-R BS.1534; k) that several broadcasters have already introduced or planned digital broadcasting services trans
8、mitting multichannel audio signals; l) that objective perceptual measurement methods may usefully complement subjective assessment methods, - 2 - C:DOCUMENTS AND SETTINGSQGV33745MY DOCUMENTSDOWNLOADSR-QUE-SG06.122-2006-MSW-E.DOC15/07/2010 decides that the following Question should be studied 1 What
9、are the characteristics of perceptual models which correlate well with perceived audio quality at intermediate audio quality levels? 2 What are the characteristics of perceptual models which correlate well with perceived audio quality for multichannel signals? 3 How may these models be used in the a
10、ssessment of audio quality? 4 What are the parameters of quality which can be measured by objective perceptual methods? 5 What are the possibilities for defining a set of test signals to be used in the objective perceptual measurement of audio quality? 6 By what criteria should the measurement methods be assessed? further decides 1 that the results of the above studies should be addressed to: include in a revision of Recommendation ITU-R BS.1387-1; prepare (a) new Recommendation(s); prepare (a) new Report(s); 2 that the above studies should be completed by 2007. Category: S1/AP
