<!--
{
  "availability" : [

  ],
  "documentType" : "symbol",
  "framework" : "QuickTime File Format",
  "identifier" : "/documentation/quicktime-file-format/Component_detect_atom",
  "metadataVersion" : "0.1.0",
  "role" : "Atom",
  "symbol" : {
    "kind" : "Atom",
    "modules" : [
      "QuickTime File Format"
    ],
    "preciseIdentifier" : "__docc_universal_symbol_reference_$Component_detect_atom"
  },
  "title" : "Component detect atom ('rmcd')"
}
-->

# Component detect atom ('rmcd')

A component detect atom specifies a QuickTime component, such as a particular video decompressor, required to play the movie.

## Overview

The component type, subtype, and other required attributes can be specified, as well as a minimum version.
Multiple component detect atoms are allowed within a given reference movie descriptor atom. Applications should not attempt to play a movie unless at least the minimum versions of all required components are present.

## Topics

### Data fields

[`Size`](/documentation/quicktime-file-format/Component_detect_atom/Size)

The number of bytes in this component detect atom.

[`Type`](/documentation/quicktime-file-format/Component_detect_atom/Type)

The type of this atom.

[`Flags`](/documentation/quicktime-file-format/Component_detect_atom/Flags)

A 32-bit integer.

[`Component description`](/documentation/quicktime-file-format/Component_detect_atom/Component_description)

A component description record.

[`Minimum version`](/documentation/quicktime-file-format/Component_detect_atom/Minimum_version)

An unsigned 32-bit integer containing the minimum required version of the specified component.


---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)