add this to /etc/squid/squid.conf

######Block Video Streaming##############

acl media rep_mime_type video/flv video/x-flv
acl media rep_mime_type -i ^video/
acl media rep_mime_type -i ^video\/
#acl media rep_mime_type ^application/x-shockwave-flash
acl media rep_mime_type ^application/vnd.ms.wms-hdr.asfv1
acl media rep_mime_type ^application/x-fcs
acl media rep_mime_type ^application/x-mms-framed
acl media rep_mime_type ^video/x-ms-asf
acl media rep_mime_type ^audio/mpeg
acl media rep_mime_type ^audio/x-scpls
acl media rep_mime_type ^video/x-flv
acl media rep_mime_type ^video/mpeg4
acl media rep_mime_type ms-hdr
acl media rep_mime_type x-fcs
acl mediapr urlpath_regex \.flv(\?.*)?$
acl mediapr urlpath_regex -i \.(avi|mp4|mov|m4v|mkv|flv)(\?.*)?$
acl mediapr urlpath_regex -i \.(mpg|mpeg|avi|mov|flv|wmv|mkv|rmvb)(\?.*)?$

http_access deny mediapr !allowed_urls
http_reply_access deny media !allowed_urls