Zooming Overview

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Revision as of 14:29, 31 July 2017 by PeterSampson (talk | contribs) (Time Scale Zooming (Horizontally): I'm minded to agree with Bill here - this is a page on "zooming" so we want the zooming gory details.)
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James 16Apr17: Suggest this page is renamed 'Zooming Overview' (same idea as Toolbar overview).
  • Peter 17Apr17: Done - with a DISPLAYTITLE rather than a rename.
Gale 19Jul15: ToDo-2 Paul has made numerous observations on this page which should be reviewed in case they improve the accuracy of this page.

Zoomen Zoomer Usando o Zoom Ampliación Zoomen

If you want to carefully inspect a small portion of your audio, or have an overview of your project, you will want to use one of these Zoom methods.
Zoom0.png

The figure above shows Audacity's view of an entire song, zoomed all the way out. It's really useful to get an idea of the whole piece from start to finish, but it's hard to see much detail - like a forest with no individual trees.

Zooming the time scale, or zooming "horizontally", is something you'll do all the time. It lets you focus on the first 15 seconds, for example:

Zoom1.png


or the last 15 seconds:

Zoom2.png


or even a tiny fraction of a second, where you can see the individual audio samples as small dots:

Zoom3.png


Occasionally you may want to zoom "vertically", so that you see only a portion of the waveform from top to bottom, but in greater detail:

Zoom4.png
If you get lost, refer to the Timeline at the top of the window. It always shows you exactly where you are in time, in hours:minutes:seconds.


Time Scale Zooming (Horizontally)

James 16Apr17: Suggest the View Menu section moves to View_Menu:_Zoom and is replaced here by a duplicate of the zoom submenu image map. Reduces the amount of duplication.
  • Bill 29Jul2017: I don't follow. On one page or the other we should get into the gory details about when the selection stays centered and when it does not, complete with images. I guess since this is the "Overview" page, then the details should be on the "Edit Menu: Zoom" page? But this page seems less an "overview" and more "details" of the various methods of zooming.
    • Peter 31Jul17: I'm minded to agree with Bill here - this is a page on "zooming" so we want the zooming gory details.


There are five ways to zoom horizontally:

View Menu

Gale 10Aug16: Commenting this out until clarified. Non-default is "on". I cannot obviously see that the setting affects zooming at selections, except for the start of the track. At the start of the track, if left of zero is off, zoom is not centered. This needs explaining better, if left in.
If "Enable scrolling left of zero" is set to be "off" (the non-default setting) then the center of the selection will be positioned at the center of screen.
  • Bill 29Jul2017: I suggest:
The zoom commands will attempt to keep the editing cursor position, or the selection, centered on the screen. That may not always be possible.

Use the zoom commands at the top of the View Menu:

  • View > Zoom > Zoom In: Doubles the current zoom level.
  • View > Zoom > Zoom Normal: Reverts back to Audacity's default zoom, where you can see 5 - 10 seconds at a time.
  • View > Zoom > Zoom Out: Cuts the current zoom level in half.
PRL 28May15: Time at screen center is unmoved, unless too near the start of track and "Enable scrolling left of zero" is off
  • View > Zoom > Zoom to Selection: If you have audio selected, this zooms and scrolls so that the selection just fits in the window.
PRL 28May15: Make a clip, use time shift to drag it partly left of zero, double click the clip, and use this command. Results are anomalous. Width is correct for the selection but horizontal position is not. "Enable scrolling left of zero" does not change that.
  • Bill 29Jul2017: This appears to be fixed.
  • View > Track Size > Fit to Width: Zooms out just enough so that you can see the entire project.
  • PRL 28May15: If some audio is shifted left of zero, it does not display. "Enable scrolling left of zero" does not change that.

    Bill 29Jul2017:

    • This appears to be fixed: if "Enable scrolling left of zero" is on, "Fit to Width" does display the audio left of zero.
    • Why is this command in the Track Size menu? It doesn't change the track size, it zooms.
    • Is it "Fit to Width", "Fit Project in Window" (see shortcuts, below) or "Fit Project" (see toolbar image, below)? The menu item is "Fit to Width".
  • View > Track Size > Fit to Height: This does not actually zoom, but resizes all the tracks so they fit in the window vertically without scrolling. If you have more than about ten tracks, some scrolling up and down will still be needed, because there is a minimum track height beyond which reduction is impossible.
  • Bill 29Jul2017: If this command doesn't zoom, why is it on the Zooming page?

    James 30Jul17: Fit-to-Width and Fit-to-Height belong together, because both are about using the track display area to the full. We do want to draw attention to that connection. That's the reason. Whether it's a good enough reason is for others to decide.

    Edit Toolbar

    Four of the view commands have equivalent buttons on the right of the Edit Toolbar:

    This image will automagically be replaced by the Annotated version ZoomToolbarAnnotated.png image, when it is ready
    • ZoomIn.png Zoom In
    • ZoomOut.png Zoom Out
    • ZoomSel.png Zoom to Selection
    • ZoomFit.png Fit Project in Window

    Keyboard shortcuts

    All six zoom commands have keyboard shortcut equivalents:
    PRL 28May15: ditto, sequence
    Zoom action Keyboard shortcut
    Zoom In Ctrl + 1
    Zoom Normal Ctrl + 2
    Zoom Out Ctrl + 3
    Fit Project in Window Ctrl + F
    Fit Vertically Ctrl + Shift + F
    Zoom to Selection Ctrl + E

    Mac users: Use instead of Ctrl.

    Zoom Tool

    You can also zoom in and out using the zoom tool Zoom Tool.


    Zoom In or Out on the Mouse Pointer using the Scroll Wheel

    If your mouse has a scroll wheel or ball, you can zoom in or out centered on the position of the mouse pointer, instead of centered on the selection or editing cursor.

    When extremely zoomed out, or when zooming in or out near the beginning or end of the track, it may not be possible to keep the audio centered on the mouse pointer position.

    Hold down the Ctrl key on your keyboard then scroll up to zoom in, or scroll down to zoom out. For example. you can zoom in at or near the start or end of a selection by placing the pointer there.

    Mac users: Hold down both and Ctrl while using the scroll wheel.
    To zoom the waveform in Audacity without using the Ctrl key, look in these places, depending on which version of macOS/Mac OS X you are using:
    • in the System "Mouse" Preferences (in older versions of Mac OS X before the Magic Mouse), disable "Zoom using scroll ball while holding Command" (or similar).
    • in the System "Universal Access" Preferences, the "Seeing" tab, then in the "Zoom" section click the "Options" button - uncheck "Use scroll wheel with modifier keys to zoom"
    • in the System "Accessibility" Preferences, click on "Zoom" in the left panel, then uncheck "Use scroll gesture with modifier keys to zoom".

    Note: When Scrubbing or Seeking, the zoom buttons in Edit Toolbar and the zoom items in View Menu (or their shortcuts) also zoom at the mouse pointer and not at the selection or editing cursor.


    Vertical zooming

    Vertical zooming can be useful on occasions. You can zoom vertically whichever of the tools in Tools Toolbar are selected. Hover the mouse over the vertical scale of a track, and the pointer changes to a magnifying glass, indicating you can zoom vertically:

    Zoom5.png
    • Left-click once to zoom in at the position on the vertical scale you are interested in. This point will then be centered on the vertical scale.
    • Hold Shift then left-click (or just right-click) to zoom out incrementally.
    • Hold Shift then right-click to zoom out immediately to normal zoom level.
      • Ctrl + Shift with left-click can also be used to zoom out to normal on Mac.

    Alternatively, click once and hold down the mouse button, then drag to select a vertical region:

    Zoom6.png

    When you release the mouse button, exactly the range you selected will be zoomed in so as to fit vertically inside the track height:

    Zoom7.png

    If you commence a drag to zoom in by mistake, you can press Esc before releasing the mouse to cancel the zoom operation.

    In default Waveform view set in the Track Dropdown Menu you can zoom in to a minimum display range of 0.001 linear extending from top to bottom of the scale.