Teledyne Lecroy Frontline BPA 600, Hardware And Software User Manual, Page: 216 / 348

The Glitch event is reported whenever an extremely large sample to sample amplitude transition occurs that
has little or no probability of occurring within natural speech or music. As illustration, back to back +N, -N, …,
+N, -N values (where N is any non-zero number), represents energy at the Nyquist frequency, or ½ the
sample rate. Neither speech nor music contain average energy levels at this frequency more the 20 dB below
nominal. However, moderately large sample to sample changes in amplitude do occur, and these naturally
limit how sensitive this measure can be configured.
The system uses back to back transition levels of 90 dB for music and 40 dB for speech as the threshold for
reporting the Glitch event.
Such dramatic changes would typically happen only in the face of dropped samples, and serve as an additional
means of detecting gross abnormalities
4.5.5 Audio Expert System™ Window
(Click here to see an introduction video...)
This window is the working space for the Audio Expert System™. Upon opening Audio Expert System™ the
window shown below will open with four main areas displayed :
l
Global Toolbar - Provides play cursor controls, waveform viewing controls, and volume controls that affect
all Wave Panels.
l
Wave Panel - Displays the waveforms for each captured audio stream. There is a separate Wave Panel for
each stream. Each panel contains local information, controls, and an event timeline specific to the
displayed audio stream being shown. Other Wave Panels that may be off scream may be viewed using the
vertical scroll control or by collapsing other Wave Panels.
l
Event Timeline - The Event Timeline shows Bluetooth events, Codec events, and Audio events
synchronized to the displayed waveform. There is an Event Timeline in each Wave Panel.
l
Event Table – A tabular listing of Bluetooth , codec, and audio events with information on event severity,
related Bluetooth frame, timestamp, and event information.
Figure 4.123 - Audio Expert System™ Window
Chapter 4 Capturing and Analyzing Data TELEDYNE LECROY
Frontline BPA 600 Hardware & Software User Manual 208