Reference Audio File Structure
The Reference Audio files typically have a structure such as listed in the example below. Such a file structure provides known variations in amplitude and frequency that enable a variety of measurements including the detection of changes to amplitude, frequency, and duration (lost audio, substituted audio).
- Test ID segment
- a 300 Hz tone segment at -12 dBFS for 100 ms
- a 600 Hz tone segment at 0 dBFS (full amplitude) for 50 ms
- a dual tone segment consisting of equal amplitude 880 and 240 Hz tones at -6 dBFS below maximum for 200 ms
- a silence segment for 100 ms
- 600 Hz tone segment which fades out over 100 ms