Custom dictionaries
Our Custom Dictionary functionality biases the speech recognition algorithms used by Amazon Transcribe and Speechmatics towards a specific set of terms, improving transcription accuracy for content containing:
- Product names
- Technical jargon
- People’s names
- Brand-specific terminology
This is particularly useful when you know the vocabulary that is likely to appear in a video.
Creating a Custom Dictionary
Before using the Custom dictionary feature, you’ll need to create one:
- Open the Custom dictionaries page from the sidebar
- Click New custom dictionary
- Give it a name and select the language for your dictionary
- Click Create & add terms
- Add your terms (we recommend fewer than 1,000 entries) using one of the following options:
- Add terms manually: type them manually or paste them in bulk (from a text editor or spreadsheet)
- Paste list of terms: paste the terms separated by new lines
- Import from CSV: choose or drag and drop a CSV file
- Generate terms from a source: extract terms from a document (up to 25,000 characters at a time)
- Click Submit or Update to save the terms to your dictionary
Note: Large custom dictionaries can reduce transcription quality, although they do not affect transcription latency. If your dictionary contains a large number of entries, CaptionHub will display a warning.
The Sounds like field is optional and can be used when a term's spelling does not clearly indicate its pronunciation. This is useful for names, product names, abbreviations or terms such as Porsche 911 or .NET.
CaptionHub will automatically suggest when a pronunciation hint may be helpful, although you can also refer to the Custom Dictionary examples for guidance.
Add terms directly from the caption editor
You can now add words to your Custom Dictionary directly while editing original captions:
- While editing a caption (in your original captions), highlight and right-click the word you want to add.
- Click the Add to Custom dictionary option.
- Choose the target dictionary and edit the Text and Sounds like fields if required.
- Hit Submit — the word is now part of your dictionary and will be used for future transcriptions.
This allows you to improve future transcriptions without leaving the editor.
Using a Custom Dictionary in transcription
Having created your custom dictionary, you then need to specify it when you create a transcription:
- Click on the Create captions button, and choose Auto-transcribe
- If Amazon Transcribe or Speechmatics is selected, choose the custom dictionary you want to use.
- Make sure your preferred transcription provider is enabled under Team settings > Transcription.
- Select the custom dictionary you'd like to use, and specify everything else as you would usually
Set a default dictionary
To automatically apply a specific dictionary to all original captions:
- Go to Team settings > Custom dictionaries
- Click the kebab menu (⋮) next to your dictionary
- Select Mark as default
The default dictionary will be applied when:
- You're auto-transcribing from the Original Captions tab in the UI
- You're using automation templates under the Original tab
Language variants
Custom dictionaries automatically work across regional variants of the same language. As long as the base ISO language matches, you only need to maintain a single dictionary.
For example, a dictionary created for English (UK) can also be used with English (US) or English (Global).
This behaviour applies when:
- Auto transcribing from the Original captions tab
- Using Automation templates