B.1 General
26.1323GPPRelease 18Speech and video telephony terminal acoustic test specificationTS
In this annex, a reference algorithm for evaluation of the echo control characteristics is described in pseudo code. The output of an implementation of the test method with the stimuli from the file "echo_control_reference_files.zip" should equal the results presented in Table 3a and Table 3b. To run the verification, the additional file named "p501-downlink_WB.pcm" in the pseudo code shall be created from the concatenated full band speech samples FB_female_conditioning_seq_long.wav and FB_male_female_single-talk_seq.wav from ITU-T Recommendation P.501, and processed with the following set of commands based on ITU-T Recommendation G.191:
filter -down HQ3 far_end_signal_48k.pcm far_end_signal_16k.pcm
filter P341 far_end_signal_16k.pcm p501-downlink_WB.pcm
Table 3a: Characterization of segment 1.
|
Double talk |
Single talk |
|||
|
Category |
Activity |
Av. Level [dB] |
Activity |
Av. Level [dB] |
|
A1 |
60,8% |
-1,2 |
95,1% |
0,1 |
|
A2 |
39,2% |
-5,1 |
1,4% |
-4,8 |
|
B |
0,0% |
0 |
0,0% |
0 |
|
C |
0,0% |
0 |
0,0% |
0 |
|
D |
0,0% |
0 |
0,0% |
0 |
|
E |
0,0% |
0 |
0,3% |
9,4 |
|
F |
0,0% |
0 |
3,2% |
8,7 |
|
G |
0,0% |
0 |
0,0% |
0 |
Table 3b: Characterization of segment 2.
|
Double talk |
Single talk |
|||
|
Category |
Activity |
Av. Level [dB] |
Activity |
Av. Level [dB] |
|
A1 |
50.2% |
-1.1 |
93,8% |
0,2 |
|
A2 |
40.8% |
-7.3 |
0,3% |
-5.6 |
|
B |
1.2% |
-16,9 |
0,0% |
0 |
|
C |
7.1% |
-17,2 |
0,0% |
0 |
|
D |
0,0% |
0 |
0,0% |
0 |
|
E |
0,0% |
0 |
0,5% |
9,5 |
|
F |
0,7% |
4.0 |
5.5% |
6,2 |
|
G |
0,0% |
0 |
0,0% |
0 |
The pseudo-code reference algorithm produces a text file output, and the implementation of the test method may be tested with the test script on the data in the file "echo_control_reference_files.zip" for which the result shall equal
ms01-rec2; segm. 1; Processed signal;
active speech level [dBovl]; -45.8; RMS level [dBovl]; -51.5; speech activity; 0.269
ms01-rec2; segm. 1; Near end signal;
active speech level [dBovl]; -42.6; RMS level [dBovl]; -49.1; speech activity; 0.225
ms01-rec2; segm. 1; Downlink signal;
active speech level [dBovl]; -26.6; RMS level [dBovl]; -27.4; speech activity; 0.823
ms01-rec2; segm. 1; delay 0; DL delay 0;
DT activity 0.100; 0.608; 0.392; 0.000; 0.000; 0.000; 0.000; 0.000; 0.000;
ms01-rec2; segm. 1; delay 0; DL delay 0;
DT level diff; -1.2; -5.1; 0.0; 0.0; 0.0; 0.0; 0.0; 0.0;
ms01-rec2; segm. 1; delay 0; DL delay 0;
ST activity 0.664; 0.951; 0.014; 0.000; 0.000; 0.000; 0.003; 0.032; 0.000;
ms01-rec2; segm. 1; delay 0; DL delay 0;
ST level diff; 0.1; -4.8; 0.0; 0.0; 0.0; 9.4; 8.7; 0.0;
ms01-rec2; segm. 2; Processed signal;
active speech level [dBovl]; -42.0; RMS level [dBovl]; -44.4; speech activity; 0.581
ms01-rec2; segm. 2; Near end signal;
active speech level [dBovl]; -40.6; RMS level [dBovl]; -42.7; speech activity; 0.625
ms01-rec2; segm. 2; Downlink signal;
active speech level [dBovl]; -26.5; RMS level [dBovl]; -27.2; speech activity; 0.841
ms01-rec2; segm. 2; delay -1; DL delay 0;
DT activity 0.348; 0.502; 0.408; 0.012; 0.071; 0.000; 0.000; 0.007; 0.000;
ms01-rec2; segm. 2; delay -1; DL delay 0;
DT level diff; -1.1; -7.3; -16.9; -17.2; 0.0; 0.0; 4.0; 0.0;
ms01-rec2; segm. 2; delay -1; DL delay 0;
ST activity 0.362; 0.938; 0.003; 0.000; 0.000; 0.000; 0.005; 0.055; 0.000;
ms01-rec2; segm. 2; delay -1; DL delay 0;
ST level diff; 0.2; -5.6; 0.0; 0.0; 0.0; 9.5; 6.2; 0.0;