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filter is not described

mime_types filter-hook . WP 3.5.0

Filters the list of mime types and file extensions.

This filter should be used to add, not remove, mime types. To remove mime types, use the 'upload_mimes' filter.

Usage

add_filter( 'mime_types', 'filter_function_name_7888' );
function filter_function_name_7888( $wp_get_mime_types ){
	// filter...

	return $wp_get_mime_types;
}
$wp_get_mime_types(array)
Mime types keyed by the file extension regex corresponding to those types.

Changelog

Since 3.5.0 Introduced.

Where the hook is called

wp_get_mime_types()
mime_types
wp-includes/functions.php 2715-2820
return apply_filters(
	'mime_types',
	array(
		// Image formats.
		'jpg|jpeg|jpe'                 => 'image/jpeg',
		'gif'                          => 'image/gif',
		'png'                          => 'image/png',
		'bmp'                          => 'image/bmp',
		'tiff|tif'                     => 'image/tiff',
		'ico'                          => 'image/x-icon',
		// Video formats.
		'asf|asx'                      => 'video/x-ms-asf',
		'wmv'                          => 'video/x-ms-wmv',
		'wmx'                          => 'video/x-ms-wmx',
		'wm'                           => 'video/x-ms-wm',
		'avi'                          => 'video/avi',
		'divx'                         => 'video/divx',
		'flv'                          => 'video/x-flv',
		'mov|qt'                       => 'video/quicktime',
		'mpeg|mpg|mpe'                 => 'video/mpeg',
		'mp4|m4v'                      => 'video/mp4',
		'ogv'                          => 'video/ogg',
		'webm'                         => 'video/webm',
		'mkv'                          => 'video/x-matroska',
		'3gp|3gpp'                     => 'video/3gpp', // Can also be audio
		'3g2|3gp2'                     => 'video/3gpp2', // Can also be audio
		// Text formats.
		'txt|asc|c|cc|h|srt'           => 'text/plain',
		'csv'                          => 'text/csv',
		'tsv'                          => 'text/tab-separated-values',
		'ics'                          => 'text/calendar',
		'rtx'                          => 'text/richtext',
		'css'                          => 'text/css',
		'htm|html'                     => 'text/html',
		'vtt'                          => 'text/vtt',
		'dfxp'                         => 'application/ttaf+xml',
		// Audio formats.
		'mp3|m4a|m4b'                  => 'audio/mpeg',
		'aac'                          => 'audio/aac',
		'ra|ram'                       => 'audio/x-realaudio',
		'wav'                          => 'audio/wav',
		'ogg|oga'                      => 'audio/ogg',
		'flac'                         => 'audio/flac',
		'mid|midi'                     => 'audio/midi',
		'wma'                          => 'audio/x-ms-wma',
		'wax'                          => 'audio/x-ms-wax',
		'mka'                          => 'audio/x-matroska',
		// Misc application formats.
		'rtf'                          => 'application/rtf',
		'js'                           => 'application/javascript',
		'pdf'                          => 'application/pdf',
		'swf'                          => 'application/x-shockwave-flash',
		'class'                        => 'application/java',
		'tar'                          => 'application/x-tar',
		'zip'                          => 'application/zip',
		'gz|gzip'                      => 'application/x-gzip',
		'rar'                          => 'application/rar',
		'7z'                           => 'application/x-7z-compressed',
		'exe'                          => 'application/x-msdownload',
		'psd'                          => 'application/octet-stream',
		'xcf'                          => 'application/octet-stream',
		// MS Office formats.
		'doc'                          => 'application/msword',
		'pot|pps|ppt'                  => 'application/vnd.ms-powerpoint',
		'wri'                          => 'application/vnd.ms-write',
		'xla|xls|xlt|xlw'              => 'application/vnd.ms-excel',
		'mdb'                          => 'application/vnd.ms-access',
		'mpp'                          => 'application/vnd.ms-project',
		'docx'                         => 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
		'docm'                         => 'application/vnd.ms-word.document.macroEnabled.12',
		'dotx'                         => 'application/vnd.openxmlformats-officedocument.wordprocessingml.template',
		'dotm'                         => 'application/vnd.ms-word.template.macroEnabled.12',
		'xlsx'                         => 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
		'xlsm'                         => 'application/vnd.ms-excel.sheet.macroEnabled.12',
		'xlsb'                         => 'application/vnd.ms-excel.sheet.binary.macroEnabled.12',
		'xltx'                         => 'application/vnd.openxmlformats-officedocument.spreadsheetml.template',
		'xltm'                         => 'application/vnd.ms-excel.template.macroEnabled.12',
		'xlam'                         => 'application/vnd.ms-excel.addin.macroEnabled.12',
		'pptx'                         => 'application/vnd.openxmlformats-officedocument.presentationml.presentation',
		'pptm'                         => 'application/vnd.ms-powerpoint.presentation.macroEnabled.12',
		'ppsx'                         => 'application/vnd.openxmlformats-officedocument.presentationml.slideshow',
		'ppsm'                         => 'application/vnd.ms-powerpoint.slideshow.macroEnabled.12',
		'potx'                         => 'application/vnd.openxmlformats-officedocument.presentationml.template',
		'potm'                         => 'application/vnd.ms-powerpoint.template.macroEnabled.12',
		'ppam'                         => 'application/vnd.ms-powerpoint.addin.macroEnabled.12',
		'sldx'                         => 'application/vnd.openxmlformats-officedocument.presentationml.slide',
		'sldm'                         => 'application/vnd.ms-powerpoint.slide.macroEnabled.12',
		'onetoc|onetoc2|onetmp|onepkg' => 'application/onenote',
		'oxps'                         => 'application/oxps',
		'xps'                          => 'application/vnd.ms-xpsdocument',
		// OpenOffice formats.
		'odt'                          => 'application/vnd.oasis.opendocument.text',
		'odp'                          => 'application/vnd.oasis.opendocument.presentation',
		'ods'                          => 'application/vnd.oasis.opendocument.spreadsheet',
		'odg'                          => 'application/vnd.oasis.opendocument.graphics',
		'odc'                          => 'application/vnd.oasis.opendocument.chart',
		'odb'                          => 'application/vnd.oasis.opendocument.database',
		'odf'                          => 'application/vnd.oasis.opendocument.formula',
		// WordPerfect formats.
		'wp|wpd'                       => 'application/wordperfect',
		// iWork formats.
		'key'                          => 'application/vnd.apple.keynote',
		'numbers'                      => 'application/vnd.apple.numbers',
		'pages'                        => 'application/vnd.apple.pages',
	)
);

Where the hook is used (in WP core)

Usage not found!