Audio Waveform Panel

The Audio Waveform Panel displays the captured audio waveform. If the waveform is stereo, both channels are visible in the Wave Panel. The user can view the entire waveform or can zoom to view a portion of the waveform in more detail.

Waveform Panel Information Tags

Audio Waveform Panel in the Wave Panel

 

Global Toolbar Waveform Horizontal Zoom Controls
Control Description
Audio Expert System zoom out Horizontal Zoom: Increases the amount of data that is visible on the screen; however, less detail is discernible.
Audio Expert System zoom out Horizontal Zoom: Decreases the amount of data that is visible on the screen; however, more detail is discernible.

Waveform

Waveform panel amplitude scale in dB

The audio waveform is plotted as amplitude versus time on the Wave Panel. The amplitude scale is located on the left edge of the Wave Panel. The waveform’s amplitude can be linear or in decibels. The linear range is -1.0 to +1.0. The range for the dB scale is 0 dB for the maximum positive and maximum negative values, and silence is negative infinity. A toggle switch at the bottom of the amplitude scale will switch between Linear scale and dB scale. Moving the switch to the left will display the Linear scale and moving it to the right will display the dB scale.

 

Play Cursor

The Play Cursor is identified by a white vertical line on the Wave Panel. The Play Cursor appears when user clicks on any point in the waveform, or, if the cursor is already present it can be dragged to another position. To drag the Play Cursor, hover the mouse cursor over the Play Cursor until the mouse cursor changes to a pointing hand; click and drag the cursor to a new position.

Waveform Segment Selection

Waveform Viewer Selection

Selection in the Audio Waveform

A waveform segment selection is identified by a blue border surrounding the selection. Procedures for selecting a segment depend on the desired actions.

Segment Selection Procedures
Desired Action Procedure
Loop play back

1. Zoom in to the waveform segment of interest.

2. Click in the approximate center of the proposed selection. This will place the Play Cursor in the area to be selected.

3. Move the mouse cursor to the right or left of the Play Cursor, click and hold, then drag over the waveform segment of interest. Release the mouse key. The selection is surrounded by a blue border.

View waveform details

1. Zoom in to the segment of interest.

2. Move the mouse cursor to the right or left limit of the waveform segment of interest; click and hold, then drag over the waveform segment of interest. Release the mouse key. The selection is surrounded by a blue border.

For either of the procedures described in the table above, once the selection is made details of the segment appear below and to the left of the waveform. These details include selection start and stop range ("T0" and "T1"), the time difference ("dT"), samples selected, frequency, and "Bluetooth Frames" selected.

Right-clicking in the Waveform panel will open a pop up menu (see "Wave Panel & Event Table Pop-up Menu". Selecting Zoom to Selection will expand the selection to the full width of the Wave Panel. Other selection option in the pop up are Select Area, Clear Selection, and Copy Selection.

Actual Bitrate Overlay Display

Actual Bit Rate View

Actual Bitrate Overlay

The Average and Actual audio stream bitrate graphs can be displayed over the audio waveform using the Global Toolbar Average Bitrate Overlay Average Bitrate Overlay and Actual Bitrate Overlay Actual Bitrate Overlay buttons respectively. These are presented as overlays onto the main Wave Panel so the user can correlate audio issues with bitrate changes and the like. The scale is in kbps (kilo bits per second). Hovering over the bitrate scale will display a pop-up showing the bitrate at the play cursor position.

Actual Bitrate is based on the throughput at the Codec level.

The Average Bitrate is the moving average over 0.1 sliding-second window.

Average Bitrate Display

Average Bitrate Overlay

All of the information for calculating the Acutal and Average Bitrate is in the codec data frame header.