1、 International Telecommunication Union ITU-T P.505TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1(06/2012) SERIES P: TERMINALS AND SUBJECTIVE AND OBJECTIVE ASSESSMENT METHODS Objective measuring apparatus One-view visualization of speech quality measurements results Amendment 1: New Appe
2、ndix II Online tool for quality pie charts Recommendation ITU-T P.505 (2005) Amendment 1 ITU-T P-SERIES RECOMMENDATIONS TERMINALS AND SUBJECTIVE AND OBJECTIVE ASSESSMENT METHODS Vocabulary and effects of transmission parameters on customer opinion of transmission quality Series P.10 Voice terminal c
3、haracteristics Series P.30 P.300 Reference systems Series P.40 Objective measuring apparatus Series P.50P.500Objective electro-acoustical measurements Series P.60 Measurements related to speech loudness Series P.70 Methods for objective and subjective assessment of speech quality Series P.80 P.800 A
4、udiovisual quality in multimedia services Series P.900 Transmission performance and QoS aspects of IP end-points Series P.1000 Communications involving vehicles Series P.1100 Models and tools for quality assessment of streamed media Series P.1200 Telemeeting assessment Series P.1300 Statistical anal
5、ysis, evaluation and reporting guidelines of quality measurements Series P.1400 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T P.505 (2005)/Amd.1 (06/2012) i Recommendation ITU-T P.505 One-view visualization of speech quality measurements results Amendment 1 New A
6、ppendix II Online tool for quality pie charts Summary In accordance with Recommendation ITU-T P.505, Amendment 1 to this Recommendation describes an online tool for the creation of quality pie diagrams that will be available for download in graphical format. New Appendix II is intended to provide so
7、me useful information for the use of this tool. History Edition Recommendation Approval Study Group 1.0 ITU-T P.505 2005-11-29 12 1.1 ITU-T P.505 (2005) Amd. 1 2012-06-07 12 ii Rec. ITU-T P.505 (2005)/Amd.1 (06/2012) FOREWORD The International Telecommunication Union (ITU) is the United Nations spec
8、ialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them
9、with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T R
10、ecommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used fo
11、r conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Rec
12、ommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any
13、party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Propert
14、y Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, imple
15、menters are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2012 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior writte
16、n permission of ITU. Rec. ITU-T P.505 (2005)/Amd.1 (06/2012) 1 Recommendation ITU-T P.505 One-view visualization of speech quality measurements results Amendment 1 New Appendix II Online tool for quality pie charts (This appendix does not form an integral part of this Recommendation.) Only technical
17、 experts can interpret the numerous complex parameters that determine the quality of telecommunication equipment as well as the end-to-end quality. This tool provides a novel methodology for quality representation, which is both easy to use and easy to understand for non-experts and which can serve
18、as a basis for commercial decisions on a management or marketing level. It offers: quick and easy recognition of expected speech quality problems for selected parameters (limit value violation); assessment of strengths and weaknesses of signal processing implemented in a terminal or other telecommun
19、ication equipment, including end-to-end considerations (quality statement); easy comparison of different equipment or connections based on the corresponding representations; easy extension of the representation by new parameters that will be relevant to quality in the future. II.1 Introduction The o
20、ne-view visualization methodology is based on the allocation of individual circle segments to the selected parameters the so-called “quality pie“. A maximum number of 16 different segments is considered here for practical reasons. The total number of parameters represented determines the size of the
21、 individual segments in the quality pie. The axes are shown with a common origin. The individual circle segments have the same size (spanned angle 360 divided by number of selected quality parameters). The representation of individual segment sizes is not interdependent, thus guaranteeing the indepe
22、ndence of the different quality parameters from each other, which leads to the following advantages: independent representation of individual quality parameters; segment sizes are determined by the number of selected parameters and are identical; segment size (radius) is a measure for the quality re
23、garding this parameter; a concentric circle around the origin is defined (1/2) which represents a minimum quality measure; falling below this segment size (radius) indicates a non-compliance with this limit value; by means of a suitable colour selection, results lying within the tolerance or transgr
24、essing the limit values can be easily visualized. 2 Rec. ITU-T P.505 (2005)/Amd.1 (06/2012) This online application of ITU-T P.505 can help the user to produce high quality graphs for individual sets of parameters. It is intended to support the use of this methodology in the field, e.g., for recurri
25、ng reporting task, but also for benchmarking or for test events. II.2 Types of axes The advantage of this tool is the ability to use different types of axes (scaling) within one quality pie, depending on user needs. There are four different types of axes. It is very important to first select the rig
26、ht type of axis for each parameter to be displayed. The different types are explained below, whereas the application of each of them is explained under operating the tool. LINEAR The linear axis type is scaling the area, based on the input values for the minimum, limit, and maximum. The minimum valu
27、e cannot be specified, it will be determined by continuing the scale defined by limit and maximum values. Any entries in the MIN section will be ignored. FOLDED The folded axis type is scaling the area and is quite similar to the linear axis type, with the important difference that this scale is lit
28、erally folded. The maximum value is not a numerical maximum but rather an optimum. For the limit there will be two values, i.e.: 1) LIMIT 2) 2 MAX LIMIT The minimum value will be determined in the same way as for the linear scale, i.e., any entries in the MIN section will be ignored and both the sca
29、le ends will be calculated as predefined by the limit and maximum values. BI-MONOTONE The axis type BI-MONOTONE scales linear (in the radius, not the area) from the origin to the limit and from the limit to the maximum. It therefore requires the input of a minimum value. The scales in both segments
30、of the axis can be as different as desired. CATEGORIAL The categorial axis type is scaling the area, equally spaced, and can be used to display results which are achieved without a scale. For the data input lines, this type is also referred to as ORDER*. The axis type ORDER* may be used to introduce
31、 ordered categorical scales (based on a declaration of the set of ordered values). See the following two examples: 1) Declaration: ORDER_DT;DUMMY;2c;2b;2a;1 e.g., for doubletalk type. The placeholder “DUMMY“ is used to initiate the axis at the origin of the segment. An axis definition might then be:
32、 ;DT Type;ORDER_DT;2b;1;2c; 2) Declaration: ORDER_LC;ORIGIN;not ok;LIMIT_VALUE;ok e.g., for “Live Call“. The placeholder “ORIGIN“ is used to initiate the axis at the origin of the segment, whereas the placeholder “LIMIT_VALUE“ is used to define the axis across the limit circle of the segment. Rec. I
33、TU-T P.505 (2005)/Amd.1 (06/2012) 3 Other ordered categorial scales can be defined as needed, but care has to be taken that the categories can be ordered in the same dimension; e.g.: “Very Good, Good, Fair, Poor, Bad“, can be ordered with sense; “Loud, Good, Noisy, Poor“, cannot be ordered because d
34、ifferent dimensions are used. II.3 Operating the tool The composition of the data input lines is done in the text box on the left side of the browser window. The separation of commands within one line is done by a semicolon (;). For many parameters no entry renders a default value. Both point (.) an
35、d comma (,) are accepted as a decimal separator. There are separate data input lines for labelling of the quality pie and its segments. The user can select a title for the plot and decide whether values and units should be displayed along with the segments. For practical reasons, user settings and v
36、alues can be imported from and exported to the users own excel spreadsheet(s). As a starting point it might be useful to export the default quality pie from the website into an excel spreadsheet and start working from there on. The “Template“ tab contains the set of data input lines, which will prod
37、uce the quality pies as contained in ITU-T P.505. They can be used as a good starting point to derive easily similar quality pies. The sectors are plotted clockwise starting at 12:00 in the sequence the data input lines are listed. The general format for data input lines creating segments is: AXIS_N
38、O;AXIS_NAME;AXIS_TYPE;MIN;LIMIT;MAX;VALUE;UNIT where usually only LIMIT, MAX and VALUE must be set. These data input lines have to be written for each segment that should be created. Buttons are placed below the data input field to assist in the creation of data input lines corresponding to the four
39、 different types of axes. AXIS_NO This entry means axis number, which by default is the consecutive number in the order of the segment command lines. Thus, switching the segment command lines will result in switching the segments in the quality pie, unless explicitly numbered (starting at 0). AXIS_N
40、AME This entry can be used to display the name of the parameter next to the outer end of the segment, if not switched off by a global setting. AXIS_TYPE This entry can be used to select the type of axis as explained above; the default setting is LINEAR. MIN The minimum value of the axis; for linear
41、and folded scales any entries in this section will be ignored; the categorial scale does also not make direct use of minimum values. 4 Rec. ITU-T P.505 (2005)/Amd.1 (06/2012) LIMIT Limit between result values considered ok and result values considered not ok. In the case of the FOLDED axis type, the
42、re will be two values displayed: 1) LIMIT 2) 2 MAX LIMIT MAX Maximum or optimum value of the axis that can be reached for this parameter. VALUE Actually achieved result value for each parameter; this determines the actual size of the coloured areas; the display of the value itself next to the outer
43、end of the segment can be enabled by a global setting. UNIT This entry can be used to add a unit to the result value, if not disabled by a global setting. A pipe symbol, i.e., “|“ will cause a line break. Global data input lines affecting the entire pie chart are: For the picture title and for the s
44、egment labelling, a pipe symbol, i.e., “|“ will cause a line break. A title for the pie chart can be set by adding a line like e.g., SHOW_TITLE;A long title for the plot. The display of the result values achieved may be enabled by adding a line like e.g., SHOW_VALUE;1. The display of the units may b
45、e disabled by adding a line like e.g., SHOW_UNIT;0. Appending a SHOW* to an axis definition line, toggles the state of the global definition of SHOW*; where * can be UNIT or TITLE. The default colouring may be changed by adding a line like e.g., COLORING_DEFAULT;#FFFFFF;#DD0000;#FFFF20;#008800. The
46、entries following the COLORING* keyword are hexadecimal RGB values with # as prefix and are mapped onto NULL, MIN, LIMIT, MAX. Non-matching inputs are rewritten as #FFFFFF. If different colouring schemes should be used per axis, they must be declared as additional entries in the data input lines app
47、ended to the general format, explained above, and referring to the relevant colouring label, e.g., ;1;2;0.8;COLORING*. Of course, such COLORING* settings should be defined before they can be referred to, e.g., COLORING_Eagle;#FFFFFF;#FF2020;#FFFF20;#77FF20. II.4 Resulting pie chart By pressing the b
48、utton “Parse and plot“ the resulting pie chart will be displayed in the right hand area(s) if the browser has session cookies enabled. Depending on the browser settings, display etc., some details may not be displayed as expected; click onto the pie chart to see the original (i.e., larger) picture,
49、which should be ok. The input data lines together with the quality pie can be exported to Excel or the graph can be saved in jpg or png format, respectively. Rec. ITU-T P.505 (2005)/Amd.1 (06/2012) 5 II.5 Parameters Examples of speech quality parameters together with typical values are to be found in Recommendation ITU-T P.505. However, the application of this tool is not limited to such parameters. In general, any kind of quality-related parameters can be used. However, it is recommended to carefully select a set of parameters which is reflect
