Skip to main content
You can only use Audio Region objects, and classifications to label audio files. See our end-to-end guide on labeling audio files to learn how to set up audio specific Ontologies.

​
Label Audio Files

Navigate to the Queue tab of your Project and select the data unit you want to label. To label an audio region:
  1. Select a Audio Region class from the left side menu.
  2. Click and drag your cursor along the waveform to apply the label between the desired start and end points. Repeat this as many times as necessary while the class is selected.
  3. If required, apply any attributes to the region.
  4. Repeat these steps for as many regions as necessary.
Audio regions can be copy-pasted using CMD / CTRL + C and CMD CTRL + V.
When assigning multiple Audio Region class labels to the same section of an audio file, hide overlapping labels.
To apply the classification to the entire audio file:
  1. Select the Classification from the left side menu.
  2. For radio buttons and checklists, select the value(s) you want to classification to have. For text classifications, enter the desired text.

​
Fill Range to the Playhead

You can quickly snap the boundary of a selected audio classification or audio region range to the current playhead (the visual marker on the timeline or waveform) position using the Fill to playhead action. This is useful when you want to extend a range to an exact point without manually dragging the timeline handle.
Position the playhead at the desired boundary point, select the audio classification/audio region range, then press Alt+V (Windows/Linux) or Option+V (Mac) to extend the nearest range edge to the playhead. You can also click Fill to playhead in the Available Actions panel in the left sidebar.
The action automatically determines which edge to move:
  • If the playhead is past the end of the range, the end boundary extends to the playhead.
  • If the playhead is before the start of the range, the start boundary extends to the playhead.
  • If the playhead is inside the range, the action does nothing — it only ever extends a range outward, never trims it.
Fill to playhead is only available for editable ranges. The action and hotkey have no effect on read-only or locked ranges.
Use Fill to playhead together with the other range-editing shortcuts for fast, keyboard-driven timeline work:

​
Editing Exact Classification Frame Ranges

When you select a classification in the left sidebar while the Label Editor is in edit mode, the frame range bounds display as editable Range start and Range end input fields instead of static text chips. This lets you type an exact frame number or timestamp to adjust a classification’s range boundary directly, without needing to drag the timeline.
Editable range inputs are only available when the Label Editor is in edit mode, the classification is selected, and the label is not read-only. When these conditions are not met, the range bounds display as static text chips as before.

​
Propagating Dynamic Attributes Across Disjointed Object Ranges

When an object appears only on disjointed (non-contiguous) frame ranges — for example, every few frames — setting a dynamic attribute normally writes only to the end of the sub-range containing the playhead. The Propagate across gaps setting changes this behavior so that the attribute value automatically covers all later sub-ranges of the same object. To enable this setting, open Timeline settings and locate the Dynamic attributes section, then turn on Propagate across gaps. The setting is off by default. When Propagate across gaps is on:
  • Setting a dynamic attribute at the playhead propagates the value forward through all later sub-ranges of the object, stopping only at the next deliberately-set keyframe for that attribute.
  • Editing or clearing a propagated value at any frame applies the change forward through all later sub-ranges from that point, while any deliberately-set later keyframe remains unchanged.
  • For checklist attributes, each option propagates independently. Only a keyframe for the same checklist option stops propagation of that option — keyframes for other options do not affect it.
When Limit to a single frame is also enabled, it takes precedence and Propagate across gaps has no effect.

​
Copy-Paste Labels

You can copy and paste Audio Region labels.
  1. Select the range(s) from the timeline.
  2. Press Ctrl + C (Windows) or Cmd + C (Mac) to copy.
  3. Click the part of the timeline you want to paste to.
  4. Press Ctrl + V (Windows) or Cmd + V (Mac) to paste.

​
Bulk Class Changes for Audio Regions

You can change the class of multiple audio regions at once using the timeline selection feature.
This feature is only available for Audio Region objects in the timeline view.
To change the class of multiple audio regions:
  1. In the audio timeline, select multiple regions by clicking and dragging across the desired regions while holding Ctrl (Windows) or Cmd (Mac).
  2. Right-click on any of the selected regions to open the context menu.
  3. Select Change class from the menu.
  4. In the Change class modal, choose the target class you want to apply to all selected regions.
  5. Click the target class to confirm the change.
The modal header displays “Change class of X selected” where X is the number of selected ranges.
All selected regions are converted to the new class while preserving their time boundaries and any existing attributes.

​
Audio Transcription

To create audio transcriptions, your Ontology must include Audio Region objects with Transcript attributes.
Navigate to the Queue tab of your Project and select the data unit you want to label.
The process outlined here assumes the Admin has configured an Ontology that includes Speaker and Transcription in the same Audio region.Audio region
To transcribe an audio region:
  1. Select an Audio Region class from the left side menu.
  2. Perform one of the following:
    • Use Timeline (Recommended): Click and drag your cursor along the Timeline under the audio file to apply the label between the desired start and end points.
    When using the Timeline, click and drag your cursor at the root for the text region to create new instances of text regions. For example for multiple Speakers.
    • Use Waveform: Click and drag your cursor along the waveform to apply the label between the desired start and end points.
  3. Fill in the content for the Speaker and for Transcription to the labeled audio region as text.
  4. Repeat these steps for as many regions as necessary.
  • When assigning multiple Audio Region class labels to the same section of an audio file, hide overlapping labels.
  • Select multiple regions using SHIFT +.
  • Bulk merge regions by selecting multiple audio regions from the same class, right-click, and click Merge ranges into and select the class to merge.

​
Transcription Pane

The Audio Transcription Pane is available when your Ontology includes at least one Transcription attribute. To access it, click the icon at the top of the Label Editor. The Transcription Pane opens on the right side, displaying all transcriptions in chronological order.

​
Long Audio Files

When audio files in your cloud storage are longer than an hour, the Label Editor may take extra time to load their waveforms. To significantly reduce load times, you can generate a JSON file containing the waveform data and store it alongside your audio file.
We STRONGLY recommend generating a waveform file for any audio files that are an hour or longer in duration.
  1. Install audiowaveform.
  2. Use the following command to generate a JSON file of your waveform:
The name of the JSON file must exactly match the name of your audio file. Only the file extensions differ.
  1. Upload the JSON file to the location of your audio file.
The JSON file MUST reside in the same cloud storage location as your audio file.For example:
  • Audio File Path in Bucket : “/my-bucket/all-audio/my-favorite-song.mp3”
  • Audio Waveform File Path in Bucket: “/my-bucket/all-audio/my-favorite-song.json”
You can upload the JSON file during audio file import or any time after.