# Timeline

From Audacity Development Manual
The Timeline displays a horizontal ruler above the tracks measuring time from zero (the start of the track). Depending on zooming the ruler may span minutes of audio or give a "close up" view of a few seconds or fractions of a second.

The Timeline is not merely an indicator of audio position but can also be used to effect Quick-Play. This functionality can be toggled on/off by right clicking in the Timeline and enabling/disabling Quick-Play (default setting is "on").

## Contents

1. The Timeline ruler
2. Symbols displayed on the Timeline ruler
3. The Timeline in use
4. Pinned Play/Record Head
5. Using Timeline Quick-Play
6. Timeline right-click menu

## The Timeline ruler

By default the basic Timeline ruler is displayed, like so:

Optionally the Scrub Ruler, the gray strip below the Timeline, can be shown too:

The Scrub Ruler is used solely for Scrubbing and Seeking and can be turned on in Interface Preferences and selecting Show Scrub Ruler in the Timeline section.

## Symbols displayed on the Timeline ruler

- The Play/Record Head button at the far left of the Timeline (shown in its default unpinned state) controls the record and play heads enabling you to toggle between unpinnned and pinned.
  - Clicking on this button will pop up a context menu enabling you to change to pinned (fixed and centered) Play/Record heads.

- The playback start position cursor. Pressing the Play button plays from this cursor position.

- The editing cursor: (always present when there is no selected region) is shown as a black vertical line.

  When "Quick-Play" is not active, the playback start position cursor is attached to it .

- The unpinned-head playback cursor: (when playing or paused during play) is shown as a large green triangle.

- The pinned-head playback cursor: (when playing or paused during play) is shown as a large green drawing-pin in the center of the Timeline.

- The unpinned-head record cursor: (when recording or paused during record) is shown as a large red triangle.

- The pinned-head record cursor: (when recording or paused during record) is shown as a large red drawing-pin in the center of the Timeline.

## The Timeline in use

  Standard playback shows:
  - The editing cursor (the black vertical bar)
  - The playback start position cursor (the left-pointing gray triangle with short gray vertical bar to left)
    - When Quick-Play is not active (see below) the editing cursor and the playback start position cursor are always at the same point on the Timeline, and together are called the standard cursor

  Recording with no selection present shows:
  - The editing cursor and the playback start position cursor (as above)
  - The recording cursor (the red triangle) - recording will continue until stopped.

  After clicking in the Timeline to initiate Quick-Play:
  - The editing cursor position is unchanged
  - The playback start position cursor moves to the point clicked
  - The green playback cursor shows the current playback position.

  After clicking and dragging in the timeline:
  - A looping region is created. Pressing Play will now loop this section over and over.
  - You can drag the in point, out point, as well as the entire looping region to different points in the timeline.

## Pinned Play/Record Head

You can change Audacity to play and record with a fixed head pinned to a position in the Timeline. In this mode the head remains static and the waveforms will move as the audio is played or recorded.

This behavior is controlled by using the button at the left of the Timeline. By default this shows as a green downwards-pointing triangle (like the play head). In this mode, the play head or record head will move horizontally and the waveform will scroll when necessary, except that if Auto-scroll if head unpinned is unchecked in Tracks Preferences then scrolling will not occur.

Clicking on the green triangle will cause a context menu to be popped up.

From that context menu you can check on Pinned Play Head. This will cause the button icon to change to a drawing-pin which indicates that the play head or record head is now pinned to the center of the Timeline and when playing or recording takes place the waveform will move continuously under the fixed head.

When pinned playback or recording is chosen, the play head displays as a static green drawing-pin and the waveform(s) will move as the audio is played (as shown in the image below). The recording head displays as a red drawing-pin.

You can revert back to unpinned playback and recording by clicking on the drawing pin and unchecking Pinned Play Head. The button will change back to the green triangle.

Unpinned or pinned head can also be selected in Transport > Transport Options.

For Scrubbing and Seeking, Audacity will ignore the setting you make for fixed head playback unless you turn "off" the option for "Always scrub unpinned" in Playback preferences.

| The default pinned position is the center of the Timeline, but you can change this by clicking on the pinned head and dragging it along the Timeline while you are playing or recording. A double-click on the head will restore it to its default position in the center of the Timeline. You may find that centered is the most useful when using playback but for recording, repositioning the head to the right may be useful.

## Using Timeline Quick-Play

Timeline Quick-Play provides a quick and convenient means to either start playback from any point within the current project. Simply click into the timeline to play from that point.

| Timeline Quick-Play is disabled during recording for safety reasons so that recording is not inadvertently interrupted.

### Clicking on the Timeline

- Left-Click: Play from the time position of the mouse pointer when clicked.
- Shift + Left-Click
  - When playback looping is enabled, this plays the looping region only once.
- Right-Click: Opens the Timeline Right-Click menu.

- Left-click + drag creates a new looping region, or moves the current looping region around.

## Timeline right-click context menu

Right-click on the Timeline gives a short context menu.

Enable dragging selection: When disabled (default), left-click and dragging the Play Region adjusts the Play Region only, leaving the current selection or editing cursor unaffected. When enabled, left-click and dragging the Play Region adjusts both the Play Region and the waveform selection together. This is particularly useful when finding the right place for a seamless loop.

Update display while playing: By default the waveform scrolls when playing. Disabling this option so as not to scroll can be useful when using Quick-Play to adjust the start and end of loops. Not scrolling ensures that the edges of the looped selection do not move if zooming in moves the playback point outside the visible area. The alternative method of disabling scrolling is to use Tracks Preferences and remove the checkmark from Auto-scroll if head unpinned.

Loop on/off: Toggles looping on and off.

Clear Looping Region: Clears any looping region

Set Loop to Selection: Sets the looping playback region to the current selection.

Pinned Play Head: You can change Audacity to play and record with a fixed head pinned to a position in the Timeline. In this mode the head remains static and the waveforms will move as the audio is played or recorded. The default setting is "off"