Label Tracks

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A "Label Track" is an additional track that can be created in your project. It is used in conjunction with audio tracks but contains no audio itself.
Features:
  • Can annotate selected points or regions of audio with text labels
  • The labels can be moved, modified or deleted.
  • Labels define different points in an audio track, so they provide a convenient way to mark different songs in a recording then export them to differently named audio files using File > Export Multiple....
a mono track with a label track, a region label and a point label

The Label Track Drop-down Menu

image of label track drop-down menu, Mac OS X style
  • Name
Displays the "Track Name" dialog where you can give the track a new name. Useful in multi-track projects to provide a visual indication of the content of each track.
  • Font
Displays the "Label Track Font" dialog where you can set the font and font size of the labels. Note that this applies to all label tracks.
  • Moving Tracks
Tracks can be moved up and down using the menu items.
Move Track Up: Moves track up.
Move Track Down: Moves track down.

Creating Labels

Suppose that you have a recording of an interview and you want to annotate the questions and answers so you can easily jump directly to a particular question or answer later on. Initially, you may have something like the image below. Without any annotation it's almost impossible to tell them apart just looking at the waveform.

A single track containing an interview with questions and answers.

Here, we select the first question with the mouse (below). This may require listening to the audio several times to determine the exact boundaries of the selection.

After selecting the first question.

Now click on Tracks > Add Label at Selection, or type its keyboard shortcut ( CTRL + B on Windows/Linux or CMND + B on the Mac). This creates a new label track and a blank label outlining the current selection (below).

After choosing Add Label at Selection.

The cursor is automatically positioned inside the label, just type the name of the label then press Enter (pressing Enter allows you to use any current keyboard shortcuts normally--you could press Space to listen to the selection again if you wished). In the image below we've typed Question 1.

After creating a label, type its name and press Enter.

After this question comes the answer from the person being interviewed. We'll select this one by starting from the right side of the answer and dragging to the left. Note that a vertical yellow guide appears when we get to the edge of the first label, making it easy to line up the two labels (below). It's common for the next label to start exactly where the previous one ends, but it's not necessary.

Selecting the audio for the second labeled region.

Once again, click on Tracks > Add Label at Selection to create the next label, then type its name and press ENTER.

Because there is already a label track, you could instead press DOWN arrow on the keyboard, so moving the yellow focus border into the label track, then just type to create the new region label and text. In most cases you can also drag a region or click in the label track, then immediately type the label for that region or point.

In the following image, we've added even more labels.

After adding the second label and naming it.

And here is a complete label track with several labels

A track with several labels.

Alternative Method Using Point Labels

In the example above we used region labels to mark the interview segments. We could just as easily have used point labels.

For example, we could click in the audio track at the beginning of the first question then click on Tracks > Add Label at Selection to create the point label.

A track with a single point label.

Similarly, we could click in the audio track at the beginning of the first answer then click on Tracks > Add Label at Selection to create the second point label.

A track with a two point labels.

Either method is equally valid. Region labels have the advantage that clicking in the label text selects the audio spanned by the region label, which may be useful in some situations.

Adding labels while playing or recording

You can also create point or region labels while playing or recording. To mark a point while playing or recording, use the command Tracks > Add Label at Playback Position or its keyboard shortcut CTRL + M. This adds a point label at the current Audio Position indicated in Selection Toolbar.

To mark a region while playing or recording, click and drag the selection region while you are listening to the track, then use the same Add Label at Selection command (or CTRL + B shortcut) as when adding a region when the track is stopped.

To hear a recording in progress, click Transport > Software Playthrough (on/off) - do not use this option when recording computer playback. See Why can’t I hear what I’m recording? for more advice.

Selecting a label

When you click inside a label to select it, the label is opened so its name can be edited, and the cursor point or region of audio the label corresponds to is restored. The cursor point or region will also be selected in any other currently selected audio tracks.

Audio in track and label selected.
You can also save and restore an individual selection region without adding a label, using Edit > Region Save and Region Restore.

Use Tab on your keyboard to select forwards to the next label, and Shift + Tab to select backwards to the previous label. If no label is selected but the Label Track has focus (shown by the yellow border), Tab will select the first label then cycle forwards through the labels, and Shift + Tab will select the last label then cycle backwards through the labels.

Removing labels

  • To remove labels without affecting other labels: Single-click in the text of an individual label, then press the DELETE or BACKSPACE key (as appropriate) on your keyboard until the text is removed. Once the label is empty of text, press DELETE or BACKSPACE once more to delete the label. You can also remove one or more labels without affecting other labels by selecting any region extending over (or at least touching) the label edges(s), then choose Edit > Remove Audio > Split Cut.
  • To remove labels (or regions of label track), affecting the following label(s): You can remove labels or regions between labels by selecting over or between labels, then choose Edit > Remove Audio > Cut or Edit > Remove Audio > Delete. If you remove part of an area inside a region label, this will reduce the length of the label. Labels following to right of the removed labels will always move backwards according to the length of the removed selection.

    When removing parts of the label track you may often want to remove the corresponding audio too, so that the remaining labels still relate to their original audio. To remove the audio region as well as the label region, either drag the selection upwards to include the audio track or enable Sync-Locked tracks.

A quick way to select and delete the exact area of an individual region label together with its corresponding audio is to single-click in the label text, then press Enter followed by DELETE or BACKSPACE.

You can also remove all labels at once by removing the label track entirely. To do this, click in the track and choose Tracks > Remove Tracks. Alternatively, click the close box in the upper-left corner of the label track.

Like everything in Audacity, any edits to label tracks can be undone by Edit > Undo.

Editing labels

Changing the length and position of labels with the mouse

You can move a label by clicking and dragging its circle handle. You can change the length of a label by clicking and dragging its triangle handle.

Holding Shift while dragging reverses this behavior, so that dragging a circle handle changes the length of the label, and dragging a triangle handle moves the label. For example, this lets you resize a label by holding Shift while dragging its circle handle, then release Shift to move the resized label without having to move the mouse pointer to its triangle handle.

In the case where two labels meet you can adjust the junction point where they meet by clicking and dragging their shared circle handle.

Moving a point label

You can move a point label by clicking and dragging its circle handle:

PointMoveBefore.png PointMoveAfter.png
Before After

Expanding a point label

You can expand a point label into a region label by clicking and dragging either of its triangle handles:

PointExpandBefore.png PointExpandAfter.png
Before After

Moving and resizing a region label

You can move a region label by clicking and dragging either of its circle handles:

RegionMoveBefore.png RegionMoveAfter.png
Before After

You can change the length of a region label by clicking and dragging one of its triangle handles:

RegionAdjustBefore.png RegionAdjustAfter.png
Before After

Adjusting the junction point where two labels meet

You can adjust the junction point where two labels meet by clicking and dragging their shared circle handle:

LinkedRegionMoveBefore.png LinkedRegionMoveAfter.png
Before After

Moving a label when there is a selection

The illustration below shows what happens if you click in a label to select it, press Enter, then move the label.

LabelRegionMove1Before.png LabelRegionMove1After.png
Before After

Contrast this to what happens if you click in a label to select it, then move the label.

LabelRegionMove2Before.png LabelRegionMove2After.png
Before After

Using cut, copy and paste

Cutting and Pasting Region Labels

You can cut and paste region labels using Edit > Remove Audio > Cut and Edit > Paste, but you have to make sure you don't select any audio, or you will end up cutting and pasting audio where you probably didn't intend.

In the image below, the label was selected by clicking in it, then the audio track was unselected by shift-clicking in the Track Control Panel of the audio track (this can also be done with the keyboard by UP then ENTER). The label was then cut to the clipboard with Edit > Remove Audio > Cut:

image of label in label track ready for Edit Cut

To paste the label at a different point in the audio track, either a) click in the audio track at the point where you would like the label to begin then shift-click in the label track to select it; or b) click in the label track at the point where you would like the label to begin. The label can then be pasted to that spot using Edit > Paste.

image of label track after Edit Paste

Cutting and Pasting Point Labels

You can also cut and paste point labels, but the procedure is tricky. In the image below, the point label is selected for editing as in the above example with a region label, but there is no selected region in the label track.

image of label track with point label selected for editing

What happens next depends on the setting of the "Select all audio in project, if none selected" preference in Tracks Preferences:

  • If that preference is not selected, Edit > Remove Audio > Cut will be disabled and pressing CTRL + X will do nothing.
  • If that preference is selected and you do Edit > Remove Audio > Cut, all audio and labels in the project will be cut to the clipboard.

To cut and paste a point label to a different location, first select the text of the label as shown below. Note the difference in appearance of selected label text (the text is highlighted separately from the box) versus a selected label (where the entire label box is highlighted).

image of label track with point label text selected

Do Edit > Remove Audio > Cut - the text of the label is cut to the clipboard, leaving a label with no text. Press DELETE to delete the label. Click in the new location for the label and do Edit > Paste Text to New Label.

image of label track after Paste Text to New Label

Using the Contextual Menu

There is a handy feature where you can select an area of text in a label then right-click to cut, copy or paste over (if there is text currently in the clipboard) that text. This allows you to click in another label, right-click, then paste that text in. So in our example you could select and copy "Question" and then paste it into the appropriate labels without having to type that word every time. The example below shows one way this can be used.

Click in a label, then select the label text. Note the difference in appearance of selected label text (as shown below - the text is highlighted separately from the box) versus a selected label (where the entire label box is highlighted). Right-click in the label:

image of contextual menu in a label with Copy selected, Mac OS X style

Now select the range of audio corresponding to the second question and click on Track > Add Label at Selection. Right click (control-click on a Mac) in the new label:

image of new label and contextual menu ready to paste text into the label, Mac OS X style

The text "Question" will be pasted into the label, and all you have to type is "2" to complete the label.

Labels Editor

Tracks > Edit Labels... launches a keyboard-accessible Labels Editor. This shows all the labels at once in a tabular view, similar to a spreadsheet:

Edit Labels dialog box with tabular view of labels

You can use the Arrow keys on your keyboard to navigate easily left, right, up or down between the table cells. To open a cell for editing, use F2 or double-click.

Opening the Start Time or End Time cell for editing lets you use Left or Right arrow keys to move between selected time digits, then Up or Down arrow keys to increment the digits. Alternatively you can type the number wanted for the selected digit.

Edit Labels dialog with time cell open for editing

Selecting any cell in the row for that label selects that label for the required action button operation, and also moves the cursor or selection region to that label in the label track itself.

The action buttons let you insert a single label before or after the selected label, or remove that selected label. There are also buttons to export all the labels to a text file (irrespective of which labels are selected), and to import a labels file. The buttons for import and export are equivalent to the File Menu commands for importing and exporting labels described below.

Keeping labels synchronized with their audio

In many cases if you delete audio preceding a label you will want the label to move back so that it still relates to the audio it related to before the deletion. To achieve this, drag the selection down into the label track before deleting. Keyboard users can include the selection in the label track by pressing DOWN then ENTER. See Selecting using the keyboard.

To keep labels synchronized after deleting audio without having to select in the label track, enable Sync-Locked Tracks at Tracks > Sync-Lock Tracks. This feature define groups of Sync-Locked audio and/or label tracks, such that a length-changing action in one track of the group affects all the others in the group, whether they are selected or not. For example, enable Sync-Lock Tracks when you want to insert audio and move the labels along as well as the audio.

See the Sync-Locked Tracks page for more information.

Importing and Exporting Labels

Existing labels are saved whenever you create an Audacity project. Sometimes it may be useful to use these labels in another program, for example if somebody wanted to know the time where each piece of an interview starts or stops. Audacity exports labels in a very simple tab-delimited plain text format that looks like this:

0.450000     0.450000     point label
1.400000     3.100000     region label
4.150000     4.150000     Question 1
5.700000     5.700000     Answer 1
8.100000     8.100000     Question 2
9.800000     9.800000     Answer 2

The first column has the start time in seconds, the second column has the end time, and the third column has the name of the label. Start time and end time are identical if the label marks the cursor position rather than a selection region. Values are separated by tab characters (shown as five spaces in the above). The exported file is called "Label Track.txt" by default. It can be opened by any text editor, or by a spreadsheet program.

You can export labels using the Edit Labels editor window, or by choosing File > Export Labels.... Labels can be imported using the Edit Labels editor window, or by choosing File > Import > Labels....

If you import labels created by some application other than Audacity, make sure the application supports UTF-8, otherwise accented or any other non-Latin characters may cause the file not to import.

If you use a Windows application to create the file, you may have to use "Save As" and look for a specific option that saves with UTF-8 encoding.

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