---
title: "Component detect atom ('rmcd')"
framework: quicktime-file-format
role: symbol
role_heading: Atom
path: quicktime-file-format/component_detect_atom
---

# Component detect atom ('rmcd')

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

## Overview

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](quicktime-file-format/component_detect_atom/size.md)
- [Type](quicktime-file-format/component_detect_atom/type.md)
- [Flags](quicktime-file-format/component_detect_atom/flags.md)
- [Component description](quicktime-file-format/component_detect_atom/component_description.md)
- [Minimum version](quicktime-file-format/component_detect_atom/minimum_version.md)

## See Also

### Describing reference movies

- [Reference movie atom ('rmra')](quicktime-file-format/reference_movie_atom.md)
- [Reference movie descriptor atom ('rmda')](quicktime-file-format/reference_movie_descriptor_atom.md)
- [Data reference atom](quicktime-file-format/reference_movie_data_reference_atom.md)
- [Data rate atom ('rmdr')](quicktime-file-format/data_rate_atom.md)
- [CPU speed atom ('rmcs')](quicktime-file-format/cpu_speed_atom.md)
- [Version check atom ('rmvc')](quicktime-file-format/version_check_atom.md)
- [Movie importer component flags](quicktime-file-format/movie_importer_component_flags.md)
- [Quality atom ('rmqu')](quicktime-file-format/quality_atom.md)