Broadcast Wave – the file format
Broadcast Wave (BWAV) is an audio format developed in 1997 by the European Broadcasting Union as an extension of the WAV standard. Unlike ordinary WAV files, it stores additional metadata such as timestamps, project information, and track markers – making it the preferred standard for broadcasting, film, and professional audio.Music productions.
The audio format explained for music production
What is a Broadcast Wave?
ABroadcast Wave(abbreviated "BWAV") is an audio file format for broadcasting andFilm productionFurthermore, it extends the familiar WAV format with additional metadata fields. These fields allow for the storage of information such as timestamps, project details, and other data. This significantly simplifies management and synchronization in professional productions.
A BWAV file therefore stores data that a normal WAV file does not. This includes, among other things:
- Time stamp:Start, end and duration of the recording.
- Project data:Project name, author and description of therecording session.
- Track marker:Markers for scene changes or sound effects.
- Manufacturer information:Information on the usedEquipment.
- Own fields:Freely definable metadata for each production.
Overall, this metadata makes Broadcast Wave particularly valuable for audio and video productions, as it improves the organization, search, and synchronization of content.
Since when has the Broadcast Wave format been around?
The format was created in 1997 by theEuropean Broadcasting Union(EBU) introduced the WAV format. The aim was to overcome the limitations of conventional WAV files, thus better meeting the requirements of broadcasting and film. Since then, it has become a widespread standard in professional productions.
What important properties does Broadcast Wave have?
Several characteristics distinguish the format. First, it isdownward compatibleIt is based on WAV and is therefore supported by many programs. Furthermore, it extends the WAV specification with metadata fields for broadcast and film. This allows project details, track markers, and custom fields to be stored centrally. In addition, the format is standardized by the EBU, which promotes its widespread use.
In addition, Broadcast Wave offers technical strengths:
- Precise timestampsfor synchronization with other media.
- Multi-channel audiofor surround sound and multi-track recording.
- Lossless data, mostly uncompressed, optionally as PCM.
- Cutting informationsuch as cut marks and editing history.
Frequently Asked Questions about Broadcast Wave
What is the difference between a Broadcast Wave and a normal WAV file?
Technically, a Broadcast Wave is a standard WAV file with an additional metadata block (the BEXT chunk). The actual audio content is identical, which is why a BWF can be played on any WAV-compatible player. The only difference lies in the embedded additional information such as timecode and source data.
What metadata does a broadcast wave file store?
The BEXT chunk contains, among other things, the originator (recording device/studio), the recording date and time, a sample-accurate time reference, and a coding history. From version 2 onwards, loudness values according to EBU R128 (inLUFS) are stored. This data makes the file uniquely traceable in professional workflows.
How does the Broadcast Wave format help with the synchronization of picture and sound?
The embedded, sample-accurate time reference allows the audio file to be automatically placed at the correct point in the timeline. This is precisely why Broadcast Wave is a common exchange format in professional audio.film soundand in radio productions, where picture and sound are recorded separately and later synchronized.
How do you open a BWF file and which programs support it?
Since a BWF file is essentially a WAV file, it can be opened by any WAV-compatible player and virtually any DAW (e.g., Reaper, Pro Tools, Cubase). The embedded metadata is primarily read by professional editing and DAW programs. If you're delivering audio to a studio, BWF is a lossless, well-documented format compared to standard PCM files – more on this in our [link to relevant article/documentation].Guide to data delivery.