Rarely used (category)
| attachment_url_to_postid() | Trying to get the attachment ID (image from the media library) by the specified attachment URL. |
| get_allowed_mime_types() | Retrieve list of allowed mime types and file extensions. |
| wp_get_audio_extensions() | Returns a filtered list of WP-supported audio formats. |
| wp_get_ext_types() | Retrieves the list of common file extensions and their types. |
| wp_get_video_extensions() | Returns a filtered list of WP-supported video formats. |
| wp_getimagesize() | Gets the image dimensions and other related information. |
| wp_read_image_metadata() | Get extended image metadata, exif or iptc as available. |