Limecraft offers extensive support for multi-channel audio. This article explains how to configure audio channel layout configuration and how multi-channel audio is used in Limecraft Flow. Please note that Limecraft does not ingest multi-channel audio by default - the default behaviour is to create proxies with a simple stereo pair. To use more complex audio channel layouts, it must be enabled first.

What is Audio Layout or Audio Channel Layout?

The Audio Channel Layout, or simply Audio Layout, refers to the details of the content of each audio channel, and the nature of sound reproduction or the way sound is played out. The two most common used Channel Layouts are mono and stereo, but also surround sound flavours and customised configurations are possible. Using Limecraft, you can qualify the different audio channels according to the nature or the language of the audio, loudness, codec, etc.

Where can I find information about the Audio Channel Layout in Limecraft Flow?

With the audio layouts you can describe in detail how the audio of a media clip is structured. For clips containing audio layout information, the clip info sidebar will contain a section ‘Audio Layout’, describing how the audio in the original media of the clip is structured:

Audio Layouts are accessible in Limecraft Flow via the item detail

Each row of the audio layout represents a so-called “Channel layout”. A channel layout represents a collection of audio channels which are meant to be played out simultaneously in a particular way. The example in the screenshot is for a clip with 4 channel layouts:

  • The first channel layout is a 5.1 mix and is in French.

  • The second channel layout is a stereo mix and is in French.

  • The third channel layout contains a 5.1 mix in the original language. 

  • The last channel layout contains a stereo mix in the original language.

When hovering the mouse over a row, Flow will show in detail which audio channels constitute this channel layout:

Audio layout detail in Limecraft Flow

So we store explicitly which particular channel is the left channel of the 5.1 French channel layout, which is the center channel, etc.

In addition, a channel layout can contain descriptive metadata. The following fields can be set on a channel layout. This is a fixed list of fields and not configurable.





A descriptive label containing more information on the contents of the channel layout


Extra descriptive notes


The language the spoken text in the audio is in. The value can be chosen from a list of languages.

Internally, this is stored as a language code (“fr”, “en”, …) but shown as the language label. Similar to how languages are treated in subtitle editor and transcriber.

We also added three “special” values to the list that do not represent a language directly but are often used to describe it:

  • International - Represents the international mix 

  • Original - Indicates this is the mix in the original language the media was in (no dubbing)

  • Unspecified - The language is not specified or not known (internally, “xx”)



The nature of the channel layout contents. It can be chosen from a limited list of values:
(Mix, R12B Mix, DVD Mix, BR Mix, Cinema Mix, TV Mix, Ambiance, Dialog, Effects, Music, Music & Effects, Options, Audio Description, STEMS, Commentary, Voice Over, VOSC, Mute)


The loudness, in units of Loudness Units (LU), of the audio mix. See also


Loudness Range (LRA)

The loudness range in units of Loudness Units Full Scale (LUFS)


True Peak

The true peak audio level, in units of decibel True Peak (dBTP).

Represents the maximum value of the signal waveform in the continuous time domain. (can be higher than the max value in the sampled domain, hence the “true” in “true peak”).



The audio codec used to encode the audio signal

Flow will fill this field in automatically, based on the media contents. It can be changed though.


Bit rate

The bit rate of the audio mix, in kilobits per second (kbps).

Initially, this will show the value calculated by Limecraft Flow based on the audio.