---
title: "Audio channel layout atom ('chan')"
framework: quicktime-file-format
role: symbol
role_heading: Atom
path: quicktime-file-format/audio_channel_layout_atom
---

# Audio channel layout atom ('chan')

An optional extension to the sound sample description specifying audio channel layouts for sound media contained in QuickTime movies.

## Overview

Overview This atom is an optional extension to the sound sample description specifying audio channel layouts for sound media contained in QuickTime movies. It is a full atom followed by a big-endian audio channel layout structure as defined by Apple’s Core Audio framework. Audio channel layouts can be applied to both compressed and uncompressed sound formats. note: Audio channel layouts with more than two channels per track require implementation with a version 2 sound sample description.

## Topics

### Data fields

- [Size](quicktime-file-format/audio_channel_layout_atom/size.md)
- [Type](quicktime-file-format/audio_channel_layout_atom/type.md)
- [Version](quicktime-file-format/audio_channel_layout_atom/version.md)
- [Flags](quicktime-file-format/audio_channel_layout_atom/flags.md)
- [Audio channel layout](quicktime-file-format/audio_channel_layout_atom/audio_channel_layout.md)

## See Also

### Extending sound sample descriptions

- [siSlopeAndIntercept atom](quicktime-file-format/sislopeandintercept_atom.md)
- [siDecompressionParam atom ('wave')](quicktime-file-format/sidecompressionparam_atom.md)
- [Format atom ('frma')](quicktime-file-format/format_atom.md)
- [Terminator atom ('0x00000000')](quicktime-file-format/terminator_atom.md)
- [MPEG-4 elementary stream descriptor atom  ('esds')](quicktime-file-format/mpeg-4_elementary_sound_stream_descriptor_atom.md)
- [Subtitle follows track reference atom ('folw')](quicktime-file-format/subtitle_follows_track_reference_atom.md)