Label Tracks

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Revision as of 13:50, 7 June 2013 by PeterSampson (talk | contribs) (Selecting a label: trimming redundant stuff from ednote - the remainder is probably redundant too)
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A Label Track is an additional track that can be created in your project. The labels in the label track can be used to reference points or regions in the project's audio tracks but the label track itself does not contain audio.

Features of a Label Track

  • Labels can be used to mark then restore chosen points or regions of audio for playback or editing.
  • Labels can contain text for purposes of annotation or transcription.
  • Labels and their text provide a convenient way to name different songs in a recorded track then export all songs at once to separate audio files using File > Export Multiple....
  • The label text can be edited and you can resize region labels or move region or point labels.
  • The Label Track's Drop-Down Menu can be used to name the track, move it up or down or set the font of all label text.
A mono audio track with a label track containing a region label and a point label
Example of a mono audio track with a label track containing a region label and a point label.
Standard Edit Menu commands can be applied to the audio of multiple labeled regions (excluding audio outside those regions). To do this, drag a selection in the Label Track that fully includes (or extends beyond) the labels whose audio is to be affected, then choose Edit > Labeled Audio and your required command.

Creating and Selecting Labels

Labels can be created by selecting a region or clicking at a point of interest then choosing Tracks > Add Label at Selection (or use its keyboard shortcut CTRL + B on Windows and Linux or COMMAND + B on Mac OS X). An empty label appears then you can type to add text to the label. Press Enter on the keyboard to confirm the text and close the label.

When the label track has the yellow focus border as in the image above you can, if preferred, just type to create a label containing that text rather than first using the menu or shortcut to create the label.

You can also create labels while playing or recording.

  • To create a point label at the current position of the green playback cursor or red recording cursor, choose Tracks > Add Label at Playback Position or its keyboard shortcut CTRL + M.
  • To create a region label while playing or recording, click and drag the region then use the same Add Label at Selection command (or its shortcut CTRL + B ) as when adding a region label when the track is stopped. Similarly you can click anywhere in a track while playing or recording and use CTRL + B to label that point.

You can create extra label tracks using Tracks > Add New > Label Track but when exporting multiple files based on labels, audio is only exported for the labels in the uppermost label track in the project.

Selecting a label

When you click inside a label to select it, the label is opened so its text can be edited, and the cursor point or region of audio the label corresponds to is restored. The region will be visible in all audio tracks that are selected and the cursor will be visible in all audio tracks that have the yellow focus border. This applies even if the label track is above the audio track.

You can use Tab on your keyboard to select forwards through each label starting from the first label (or Shift + Tab to select backwards starting from the last label) whenever the focus border is in the label track. To restore focus to the label track if necessary, either use keyboard UP or DOWN or click in empty space on the Track Control Panel of the label track (which both selects it and gives it focus).

See this page for more details on label creation and selection.

Peter 31May13: Personally I don't like that immediate label creation by typing feature, and I wouldn't recommend it or promote its use. You have to be darn sure that focus is on the right track before typing especially if you are creating labels while recording - as typing a "space" can cause the recording to stop if focus is in the wrong place and you haven't noticed. I much prefer the positive action of using Ctrl+B or Ctrl+M to create a label.
  • Gale 30May13: I don't think it was right to hide autotyping from the Manual. The feature is there and only one developer (Al Dimond - no longer active) wanted to remove it. If we mention it in the Manual, at least it doesn't look like an unexpected bug. IMO there is only a little more we can do to make it work tolerably well with single key shortcuts and when playing or recording. Other than that, the simplest solution is to supply a preference to turn it off (but I think that should be on by default).
    • Peter 31May: Fair enough, and I do agree that if the functionality is there then it should be documented. Personally I'm with Al on this - I'd remove it completely. And I don't think it needs an on/off preference. When I say "I wouldn't recommend it or promote its use" I mean I wouldn't do so in a forum response.

Removing labels

Labels can be removed (deleted) in a number of ways. Often you may want to remove labels from the label track without removing their associated audio, but also without affecting the relationship of the remaining labels to their audio. The quickest way to do this is to select any region that extends beyond the label(s) to be removed (without reaching other labels), then choose Edit > Remove Audio or Labels > Split Delete (or its shortcut CTRL + ALT + K). This will remove the selected label(s) without moving any labels that lie to right of the removed labels, so keeping those following labels synchronized with their audio.

To remove labels or a region of label track so that the following labels move back (leftwards), select over or between labels then choose Edit > Remove Audio or Labels > Delete or its shortcut CTRL + K. A typical use case is removing the region in the label track together with its associated region of audio, which you can do by including the audio track in the selection. This also keeps the following labels synchronized with their audio.

You can also remove all labels at once by deleting the label track entirely by clicking on the close button close button in the upper-left corner of the label track.

See this page for more details on label deletion.

Keeping labels synchronized with their audio

Peter 31May13: Maybe we should actually place this in the Removing Labels Page so as not to overburden this page. It certainly was wrongly placed in its previous location on the Editing, Resizing and Moving labels page.
  • Peter 6Jun13: I changed my mind about this after a long ponder. I now think it's worth having this information on both pages (slightly trimmed here for brevity). On this page for stand-alone completeness without the need to go to the sub-page. On the sub-page as an H3 subsection of the one H2 section for which it has relevance.

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.

Editing, Resizing and Moving labels

You can edit labels by changing their text content, resize region labels or move region or point labels.

You can change label positions:

  • move a point label by clicking and dragging its circle handle
  • expand a point label into a region label by clicking and dragging either of its triangle handles
  • move a region label by clicking and dragging either of its circle handles
  • change the length of a region label by clicking and dragging one of its triangle handles.
  • adjust the junction point where two labels meet by clicking and dragging their shared circle handle.

You can cut and paste region labels using Edit > Remove Audio or Labels > 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 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.

See this page for more details on editing labels.

Labels Editor

Tracks > Edit Labels... launches a keyboard-accessible Labels Editor where you can perform all remove, text edit, resize and move operations on labels. All the labels and label tracks in the project are displayed in a tabular view, similar to a spreadsheet. Each row represents a single individual label.

Advice You cannot save empty labels that have no label text using Labels Editor, even if you are editing an existing label track that contains empty labels. Any empty labels will be removed from the label track(s) after closing the editor, unless you click Cancel.

See this page for more details on the editor.

Editing or moving the label track using the Drop-Down Menu

Clicking the label track's name by the downward-pointing triangle (or using shortcut SHIFT + M or the keyboard Menu key when the label track has focus) opens the Label Track Drop-Down Menu:

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.

Label tracks can also be moved up or down by clicking between the controls in the track's Track Control Panel then dragging upwards or downwards.

Importing and Exporting Labels

Label Tracks can be exported to, and imported from plain text files ( .txt extension in Windows). The file structure is a tab-delimited plain text format that can be opened by any text editor or spreadsheet program and edited there.

See this page for more details on text label files.