<!--
{
  "availability" : [

  ],
  "documentType" : "symbol",
  "framework" : "QuickTime File Format",
  "identifier" : "/documentation/quicktime-file-format/Track_profile_atom/Feature_code",
  "metadataVersion" : "0.1.0",
  "role" : "Data field",
  "symbol" : {
    "kind" : "Data field",
    "modules" : [
      "QuickTime File Format"
    ],
    "preciseIdentifier" : "__docc_universal_symbol_reference_$Track_profile_atom_Feature_code"
  },
  "title" : "Feature code"
}
-->

# Feature code

A 32-bit unsigned integer that represents a code specifying a feature.

## Overview

The third field is the feature code, or name, a 32-bit unsigned integer that is usually best interpreted as four ASCII characters. Example: the maximum video bit rate feature has a feature code or name of `'mvbr'`. It is permissible to use a feature code value of zero (`0x00000000`, not four ASCII zero characters) as a placeholder in one or more name-value pairs. The reader should ignore feature codes of value zero.

---

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)