Zooming and navigating Plot Spectrum

[steve]

I've already voted for this feature, but prompted by a post HERE I've made a little video to demonstrate a feature that I'd like to see in Audacity. This demonstration was created by exporting data from Audacity's "Plot Spectrum", then plotting an "interactive" graph in (open source) Gnuplot. The graph allows zooming both vertically and horizontally, and provides a numeric readout of the cursor position. http://youtu.be/PlUyP_kErDc

[kozikowski]

Among other things, this gets around the problem of needing to make the analysis intentionally sloppy so you can see the spikes on the graph. Koz

[steve]

Among other things, this gets around the problem of needing to make the analysis intentionally sloppy so you can see the spikes on the graph. Koz

Not shown in that video, Gnuplot also has a feature to "smooth" the graph. That is, it averages neighbouring values to provide a less spiky curve, similar to the curve when using a small FFT "Size" setting, but from data at a very high FFT size. Because the graph is calculated from a few thousand data points (rather than millions of sample values), the smoothed curve can be calculated in real time. The potential for this is that there could be a plot mode in Plot Spectrum that produces a fairly low resolution (sloppy) graph when zoomed out, but with increasing detail when zooming in, without needing to recalculate the FFT data.