User:PeterSampson/Spectral Selection and editing with Sync-lock

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Is it supposed to work like this

Following a "throwaway" comment from James in a recent email thread I started to experiment with Spectral manipulation with sync-locked tracks - and the results I got as a reasonably proficient user of spectral stuff and a very experienced user of sync-locked tracks were more than somewhat unexpected.

Gale's quick reply

  • Sync-lock is for time selections, not frequency selections.
  • Dragging the time/frequency selection into other tracks will only show the frequency selection if each track has spectral selection enabled. The track setting can disable spectral selection even if spectral selection is turned on in Spectrograms Preferences.
  • A full height waveform in either waveform view mode also obscures the clocks wallpaper. The Spectrogram seems to be treated like a full height drawing, e.g. a sync-lock selected track containing absolute silence shows the clocks in waveform views but not in Spectrogram views.
    • Peter 29Sep15: Yes, yes and yes - but the examples below exhibit some strange and unexpected behaviors (well to me anyway). I find it hard to believe that the behaviors in the use case below were actually planned, but maybe I am wrong. But one thing I don't intend to do is document the behaviors on this page in the Manual.
    • Gale 30Sep15: Don't my three bullet points fully explain your observed behaviour? Please say if not. My reading was that you expected Sync-Lock to make spectral selection show in sync-selected tracks (if those tracks enabled spectral selection) and that you expected the clocks wallpaper to be in front of the waveform or spectrogram. If the wallpaper had user-configurable transparency then IMO it could go in front of the waveform or spectrogram.
      • Peter 01Oct15: No they don't Gale, not at all really. I think I have somewhat obscured the issue by using the sync-lock and expecting spectral propagation (I accept that "sync" locking is by its nomenclature a temporal lock). Instead try this use case with the sync-lock turned off. You will observe the same odd behaviour where you can make a spectral selection in the top track dragging it it down into the other two tracks (this of course extends the spectral selection downwards too). Release the mouse and then manipulate any of the three spectral selections and you will observe that the modified spectral selection propagates to the other two tracks. Now this may well be intended behaviour, I don't know one way or the other, but it certainly looks odd to me and I pretty sure that no design thought went into this it "just happens". Admittedly this is probably a fringe case, I would anticipate that most uses of spectral manipulation will be made on a single track - nut some users may do this inadvertently and be surprised, as I was as a tester. I also acknowledge that multiple co-ordinated spectral selections like this in multiple tracks may be useful to some users. I'm just confused ...
      • Gale 01Oct15: A1: If you create a spectral selection in a track you have by definition a time (horizontal) and frequency (vertical) selection. If you drag a "time" edge into the track below, any frequency selection within the time selection comes with the drag. A2: If you then deselect the lower track by DOWN arrow and ENTER, both the time and frequency selections are removed.

        B1: If you do step A1 again in the first track, but instead of dragging the time edge, drag the lower frequency edge (hover over that edge, hold SHIFT, then drag into the track below), then again we are dragging the frequency selection within the time selection, and both selection types come with the drag.

        C1: If you drag the frequency selection into the lower track without using SHIFT, you first select all frequencies in the time range in the upper track, then drag that time and fully-selected frequency range into the lower track. The full frequency selection is a "NULL" frequency selection which the Spectral Edit effects cannot work with, denoted by dashes in Spectral Selection Toolbar.

        Which of A1, A2, B1 and C1 are not correct or expected?

Initial state

Take this project with three tracks all displayed in spectrogram view and all with Spectral Selection turned on in their TCPS (note that there is no visual cue for this unless you return to their TCP dropdown menu for Spectrogram settings). Sync lock is turned on - there are a couple of visual cues: the small clock icon in each track's TCP plus the Sync-lock button is down.

PS Spec-sync01.png

Initial spectral selection

Now make a spectral selection in the top track say

PS Spec-sync02.png

Note that the selection is currently only present in the top track and is not propogated to the other tracks in spite of the fact that sync-lock is on (which is what I would have expected. Using the Spectral Edit multi-tool at this stage shows that indeed the selection is only in the top track as the bottom two tracks are unaffected by the edit (note the color change in the spectral selection and no color change in the other two tracks:

PS Spec-sync03.png

Drag the spectral selection downwards

Now it starts to get interesting. Drag the bottom of the spectral selection in the top track down until the cursor is in the bottom track.

PS Spec-sync04.png

A full spectrum selction in all three tracks

Drag the bottom upwards

Drag the bottom edge of say the middle track upwards

PS Spec-sync05.png

We're starting to see some proper synchronicity.

Drag the top downwards

Drag the top edge of say the bottom track downwards

PS Spec-sync06.png

The sort of synchronicity in all three tracks that I expected to see in my initial selection just in the top track.

Make a deletion

So now just make a spectral selection in say the top track again

PS Spec-sync07.png

Now make a deletion

PS Spec-sync08.png

Observe that sync-locking is observed for this action unlike above with the initial spectral edit with the selection in just the top track.

Pocket watches

The pocket watch icons to indicate a sync-lock selection are drawn, but obscured by the spectrogram display

PS Spec-sync09.png