Steinberg Wavelab Elements 8 Manual

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Audio Analysis
WaveLab Elements provides you with a comprehensive set of tools for 
analyzing your audio and for detecting any errors.
For example, you can use the suite of audio meters, or the 3D 
Frequency Analysis. There are also several tools that help you examine 
any sample of your audio for errors or anomalies.
Global Analysis
In WaveLab Elements you can perform advanced analysis on your audio 
to identify areas with specified properties. This helps you find problem 
areas such as glitches or clipped samples. You can also check general 
information, such as the pitch of a sound.
When you analyze a section of an audio file, WaveLab Elements scans 
the section or the audio file and extracts information which is displays 
in the dialog. WaveLab Elements also marks sections of the file that 
meet specific characteristics, for example, sections that are very loud or 
almost silent. You can then browse between these points, set markers, 
or zoom in on markers. On most of the tabs, you find settings that 
determine exactly how the analysis is performed. Each tab focuses on 
a particular analysis area.
You perform the global analysis in the Global Analysis dialog. This 
dialog consists of the following tabs that provide different analysis 
types:
• The Peaks tab lets you find individual samples with very high 
values.
• The Loudness tab lets you find sections with high intensity.
• The Pitch tab lets you find the exact pitch of a sound or section.
• The Extra tab provides information about DC offsets and the 
significant bit resolution. 
						

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• The Errors tab lets you find glitches and sections where the audio 
has been clipped.
Most of the analysis types provide a number of positions in the file that 
indicate peaks, glitches, etc. These points are called “hot points”.
Opening the Global Analysis Dialog
The Global Analysis dialog provides various analysis options.
PROCEDURE
1.In the Audio Files workspace, select a range in the audio file that 
you want to process.
If you want to analyze the entire file, press [Ctrl]/[Command]-A. If 
Process whole file if there is no selection is activated in the Audio file 
editing preferences dialog, the whole file is processed automatically 
provided that no selection has been made.
2. Select Analysis > Global analysis.
RELATED LINKS:
“Audio File Editing Preferences Dialog” on page 332
Choosing the Analysis Type
Several types of analysis can be performed. Each of them takes some 
time, so make sure that only the types that you need are included in the 
analysis.
Select the analysis types by activating them in the corresponding tabs.
• To include the Peaks analysis, activate Find Peaks.
• To include the Loudness analysis, activate Analyze Loudness.
• To include the Pitch analysis, activate Find Average Pitch.
• To include the Extra analysis, activate Find DC Offset.
• To include the Errors analysis, activate Find Possible Glitches 
and Find Clipped Samples. 
						

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Global Analysis - Peaks Tab
This tab is used to find digital peak values in the audio, that is, single 
samples with very high values.
In the Audio Files workspace, select Analysis > Global Analysis, and 
select the Peaks tab.
Find Peaks
Enables peak analysis.
Digital
Displays the highest peak in the analyzed section. When you click 
this value, the number of peaks that are found in the selection is 
shown in the Number of hot points section in the lower left corner 
of the dialog. You can use the hot points to move the cursor 
between the peaks.
At cursor
Displays the level at the current audio file cursor position at the 
time of the analysis.
Maximum number of peaks to report
Restricts the number of reported peaks. For example, setting this 
to “1” reports only the highest peak.
Minimum time between 2 peaks
Controls the distance between points, so they do not appear too 
close to each other. For example, setting this to “1 s” ensures that 
there is always at least one second between reported points.
Results of the Analysis
The Find Peaks fields show the highest peak in the analyzed section 
and the level of the sample at the wave cursor position at the time of the 
analysis. 
						

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Global Analysis - Loudness Tab
This tab is for finding sections that are perceived by the human ear as 
louder or weaker in volume. To find sections that the ear perceives as 
significant in volume, you must look at a longer section of audio.
In the Audio Files workspace, select Analysis > Global Analysis, and 
select the Loudness tab.
Loudness Settings
Analyze Loudness
Enables RMS loudness analysis.
Average
Displays the overall loudness of the analyzed selection.
Maximum
Displays the level of the loudest section in the analyzed selection. 
Clicking this value displays the number of loud sections found 
within the selection, in the Number of hot points section in the 
lower left corner of the dialog.
Minimum
Displays the level of the quietest section in the analyzed selection. 
Clicking this value displays the number of weak sections that are 
found within the selection in the Number of hot points section in 
the lower left corner of the dialog. This provides adequate 
information about the signal-to-noise ratio (SNR) of the audio 
material.
Around cursor
Displays the loudness at the audio file cursor position at the time 
of the analysis. 
						

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Resolution
The length of audio to be measured and averaged. If this value is 
lowered, short passages of loud/weak audio are detected. When 
it is raised, the sound must be loud/weak for a longer period to 
result in a hot point.
Threshold (for the average)
Ensures that the average value is calculated correctly for 
recordings with pauses. The value that you set here determines a 
threshold below which any found audio is considered to be 
silence, and is therefore excluded from average value calculations.
Maximum number of loudness points to report
Restricts the number of reported hot points. The highest points are 
reported. For example, setting this to “1” reports only the loudest 
section or one of the sections with the same highest value.
Minimum time between 2 points
Controls the distance between points, so they do not appear too 
close to each other. For example, setting this to “1 s” ensures that 
there is always at least one second between reported points.
Global Analysis - Pitch Tab
This tab is for finding the average pitch of an audio section.
In the Audio Files workspace, select Analysis > Global Analysis, and 
select the Pitch tab.
You can use this tab to gather information for pitch shifting, for example, 
to get one sound in tune with another. The display shows the pitch for 
each channel, both in Hertz (Hz) and as semitones and cents 
(hundredths of a semitone). Since the display shows an overall value for 
the entire analyzed section, the hot point controls in the lower section of 
the dialog are not used on this tab.
Usage guidelines for the Pitch tab:
• The result is an average value for the whole selection.
• The method only works on monophonic material, not on chords or 
harmonies.
• The algorithm assumes that the analyzed section has a reasonably 
stable pitch. 
						

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• The material must be relatively well isolated from other sounds.
• It is preferable to analyze the sustain portion of a sound rather than 
the attack. The pitch is usually not “stable” during the attack.
• Some synthetic sounds may have a weak fundamental (first 
harmonic) which can irritate the algorithm.
Global Analysis - Extra Tab
This tab shows the average DC Offset of the analyzed section and the 
Apparent Bit Resolution.
In the Audio Files workspace, select Analysis > Global Analysis, and 
select the Extra tab.
The Apparent Bit Resolution attempts to detect the actual resolution 
in the audio. This is useful, for example, if you want to check, whether a 
24-bit file really uses 24 bits or if it was actually recorded with 16-bit 
resolution and then expanded to 24 bits.
Errors Detection
You can detect errors, such as glitches and sections where the audio 
has clipped. 
Glitches
• These are disruptions in the audio. Glitches may occur after 
problematic digital transfers, after careless editing, etc. They 
manifest themselves as “clicks” or “pops” in the audio. 
						

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Clipping
• A digital system has a finite number of levels that it can represent 
properly. When recorded sound levels are too high or when the 
system cannot handle levels that have been raised by digital 
processing, hard clipping occurs that you can hear as strong 
distortion.
A sine waveform before clipping and after.
Result of the Analysis
This reports the number of glitches and clipping instances that have 
been found.
Global Analysis - Errors Tab
This tab helps you find glitches and sections where the audio has 
clipped.
In the Audio Files workspace, select Analysis > Global Analysis, and 
select the Errors tab.
Maximum number of error points to report
Allows you to restrict reported numbers of hot points.
Minimum time between 2 points
Controls the distance between points, so they do not appear too 
close to each other. For example, setting this to “1 s” ensures that 
there is always at least one second between reported points. 
						

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Find possible glitches
Enables glitch analysis.
Find possible glitches - Threshold
Sets the value at which a change in level is considered to be a 
glitch. The higher the value, the less sensitive the detection.
Find possible glitches - Sensitivity
Length value that represents the length of time in which the 
waveform must exceed the threshold to be reported as a glitch. 
The higher the value, the less sensitive the detection.
Find possible glitches - Output format
Displays the number of clipping occurrences that are found by the 
analysis. Clicking this value displays the number of clips in the 
Number of hot points section in the lower left corner of the 
dialog.
NOTE
Make sure that the points that are found by the algorithm are real 
glitches. Zoom in and play back to check whether the found points really 
indicate a problem.
Find clipped samples
Enables clipping analysis.
Find clipped samples - Threshold
Checks for a number of consecutive samples at full value, to 
determine whether clipping has occurred. The Threshold setting 
determines the exact number of these consecutive samples that 
must occur for the program to report clipping.
Find clipped samples - Output format
Displays the number of clipping occurrences that are found by the 
analysis. Clicking this value displays the number of clips in the 
Number of hot points section in the lower left corner of the 
dialog. 
						

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Performing a Global Analysis
PREREQUISITE 
In the Audio Files workspace, select Analysis > Global Analysis, and 
select the tab that you want to include in the analysis.
PROCEDURE
1. In the Global Analysis dialog, set up the parameters.
Most of the tabs have settings that determine how the analysis should be 
performed.
2. If the Peak or Loudness tab is selected, move the cursor to the 
position that you want to analyze.
The Peak and Loudness tabs report values specifically for the position of 
the cursor.
3. Click Analyze.
Results of the Global Analysis
Depending on the analysis type, one or several values are returned for 
the analyzed audio.
For the Pitch and Extra analyses, only one value is returned. The other 
analysis types provide a number of positions in the file that indicate 
peaks, glitches, etc. These points are called “hot points”.
Checking the Results of the Global Analysis
The results of the global analysis are marked with hot points. You can 
browse through these points to see the results of the analysis.
PREREQUISITE 
In the Audio Files workspace, select Analysis > Global Analysis, and 
perform the analysis.
PROCEDURE
1. In the Global Analysis dialog, click the tab that represents the 
values that you want to check.
2. Check the display for maximum/minimum values in the entire 
analyzed section.
3. Decide which of these values you want to browse.
4. Click the button that currently displays this value. 
						

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5. Check the Number of hot points value at the bottom of the dialog.
The value shows the number of positions that were found by the analysis.
6. Use the scrollbar below the Number of hot points value to 
browse between the found positions.
The edit cursor shows the position in the wave window.
7. To browse another property, click the corresponding tab, and then 
the value button.
NOTE
The result of the analysis is saved until you close the dialog or click 
Analyze again.
Creating Markers at Hot Points
Creating markers at hot points simplifies browsing the results of the 
global analysis.
PREREQUISITE 
In the Audio Files workspace, select Analysis > Global Analysis, and 
perform the analysis.
PROCEDURE
1. In the Global Analysis dialog, select the analysis type for which 
you want to create markers at hot points.
You can add markers for only one channel at a time.
2. Click the Create markers at hot points button.
Temporary markers are added at all hot points.
RESULT 
The markers are named using the following principle: “Hot point number 
(Channel)”. For example, a marker at the third hot point in the left 
channel would be labeled “3 (L)”.