Playbox QCBOX, Руководство пользователя

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Be aware that QCBox stores information for files that have already been checked with a certain Test preset. These files are recognized by their name and
QCBox verifies if the files checked are the same (i.e., the file is not a different one but with the same name) by checking its size in bytes. Thus, if for any
reason you are uncertain if the files that have already been checked correspond to the currently checked files, place a check in the

Calculate CRC
box
and QCBox will compare the size of the previously tested and the currently tested file. For more accurate results you can use the

Force Calculation
box. However, you should note that this will slow down the quality check process.
Below you can see a list of the currently available test plugins, together with their description:
Loudness Measurements – Audio
The first plug-in is designed for performing
Loudness Measurements
. Its parameters are predefined in accordance to the EBU Technical
Recommendation R 128.You can choose between two algorithms for loudness measurement, available in our system - ItU R BS 1770-3(3) or ItU R BS
1770-1(1). Read more about loudness normalizing in the corresponding section
below . You can also refer to the ITU (International Telecommunication
Union) website, http://www.itu.int/rec/R-REC-BS.1770/ , to view more information about the algorithms.
Please, refer to the table below to view the user configurable parameters for this test preset:
Parameter name Description
Choose standard to measure the loudness: ItU R BS 1770-
3(3) or ItU R BS 1770-1(1) This is the standard (algorithm) used for loudness measurement. By default, the
value is set to 3, which stands for ItU R BS 1770-3(3). If you want to use ItU R BS
1770-1(1), please set the value to 1.
Max True Peak, dBFS This is the maximum
true peak
value. By default, the value is 0. The parameter can
also be set to a negative number.
Zero Reference Level, dBFS This is the reference loudness level. By default, its value is -23. It can take a value of
0 or negative values.
Deviation from Zero Reference Level correction This parameter determines whether deviations from the Zero Reference Level
parameter should be allowed. It takes only two values, -1 and 0. By default, the
value here is set to 0, which means that deviations are not allowed. If you set the
value to -1, the check will be ignored.
The metadata file that is sent to AirBox looks like this:
<ProgrammeLoudness>floating point number</ProgrammeLoudness>
<LoudnessRange>floating point number</LoudnessRange>
<TruePeak Channel="0" Value="floating point number"/>
<TruePeak Channel="1" Value="floating point number"/>
...
<TruePeak Channel="N" Value="floating point number"/>
AirBox will use the received floating point number values and interpret them in accordance to the EBU Technical Recommendation R 128 target levels,
which are stated
below .