PHP. Руководство по PHP. 2005
mime_content_type
mime_content_type
Description
string mime_content_type (string filename)Returns the MIME content type for a file as determined by using
information from the magic.mime file.
Content types are returned in MIME format, like text/plain
or application/octet-stream.
Mimetype Functions
Ming functions for Flash
Отвечу на любые вопросы. С уважением, Дмитрий Владимирович.