Change Language Code
The FFmpeg Builder: Change Language Code flow element modifies language codes on all video, audio, and subtitle streams.
It is useful for standardizing language metadata in media files, especially when dealing with inconsistent or non-standard language codes from different sources.
This flow element examines the language code on each stream and replaces it if it matches any of the keys in the configured replacement list.
Purpose
In many video processing workflows, language codes are used to identify the audio or subtitle languages of media tracks.
However, different tools and sources often use different codes for the same language (e.g., "eng" vs "en", "cn" vs "zht").
This flow element helps normalize those language codes across your pipeline so that they are consistent, recognizable, and compatible with downstream tools such as:
- Media players (e.g., Plex, Jellyfin, Kodi)
- Metadata processors
- Transcoding workflows
- Archival or compliance standards
Replacements
A list of key-value pairs where:
- The key is the original language code to match.
- The value is the desired replacement language code.
Each replacement is applied to video, audio, and subtitle tracks separately.
The match is performed using the system’s flexible string comparison rules (e.g., case-insensitive, optionally supporting wildcards depending on config).
Example
| Key | Value |
|---|---|
| eng | en |
| fre | fr |
| cn | zht |
With the above replacements:
- A video track labeled "eng" will be changed to "en".
- A subtitle track labeled "fre" will become "fr".
- An audio stream labeled "cn" will be changed to "zht" (for traditional Chinese).
Outputs
- One or more language replacements were made.
- No replacements were performed.
Use Cases 🔁 Normalize Language Codes Across All Media You ingest content from many sources. Some label English as "eng", some as "en". This flow element makes them uniform.
🌍 Match Metadata Standards If your media cataloging system expects ISO 639-1 language codes (en, fr, de), but you receive ISO 639-2 codes (eng, fre, ger), this flow element allows you to convert them seamlessly.
📺 Improve Compatibility with Media Servers Systems like Plex or Jellyfin may show incorrect or blank language names if the codes are non-standard. Standardizing codes ensures better display and playback experience.
🧪 Pre-processing for Subtitling or Translation Ensure all subtitle tracks are correctly tagged before feeding them into a subtitle translation or OCR system that relies on accurate language detection.