Default value for frame overlap

[towsey]

The default value for frame/window overlap is currently set at 0.5. (See class SonogramConfig, line 24.)
This should be set = zero (0.0).
The frame step can be set directly or indirectly through windowOverlap. Both means are useful at different times. However currently setting one does not always set the other. In particular, setting the frame step in Generic Profiles does not reset the windowOverlap.
Changing the default windowOVerlap to zero may cause some tests to fail.

[atruskie]

I don't think this will have much effect.

We generally set window overlap to 0 almost everywhere. I doubt that default is ever actually used.

Change the default, run the tests, see if there are any failures, and we can see what the right thing to do after that it is.

As for the overlap/frameStep duality: a couple of unit tests for the SonogramConfig class should be enough to ensure they are always set consistently.

[towsey]

The default is used which is how I picked up the problem.

[atruskie]

Where?

[towsey]

Line 142 in the same class.

[atruskie]

As in:

audio-analysis/src/AudioAnalysisTools/StandardSpectrograms/BaseSonogramConfig.cs

Line 141 in 63e6299

config.SetPair(ConfigKeys.Windowing.Key_WindowOverlap, DEFAULT_WINDOW_OVERLAP.ToString());

Then yes, the default is set. But we override it almost everywhere. Have you found a case where that default is actually used in real-world code?

[atruskie]

Discussed offline. It looks like the root cause of this was introduced in

https://github.com/QutEcoacoustics/audio-analysis/blame/2b9fa60caf62955083a75731be644bc8088f9485/src/AnalysisPrograms/Recognizers/GenericRecognizer.cs#L295