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BroadcastsIn the United States, 1080p over-the-air broadcasts still do not exist as of 2010; all major networks use either 720p60 or 1080i60 encoded with MPEG-2. However, satellite services (e.g. DirecTV, XstreamHD, and Dish Network) utilize the 1080p/24-30 format with MPEG-4 AVC/H.264 encoding for PPV movies that are downloaded in advanced via satellite or on demand via broadband internet only. At this time, no pay service channel such as USA, HDNET, etc. nor premium movie channel such as HBO, etc., stream their services live to MVPD's using this format because many MVPD's, especially DBS and cable, do not have sufficient bandwidth to provide the format streaming live to its subscribers without negatively impacting their current services and because of the high "cost" of using more bandwidth for one 1080p/24 channel than what would be used for a 1080i or even a 720p channel and for only those relatively few who have HDTV's that can display 1080p/24 as not being an efficient use of their limited bandwidth.
For material that originated from a progressive scanned 24 frame/s source (such as film), MPEG-2 allows the video to be coded as 1080p24, irrespective of the final output format; these progressively-coded frames are tagged with metadata (literally, fields of the PICTURE header) instructing a decoder how to perform a 3:2 pulldown to interlace them. While the formal output of the MPEG-2 decoding process from such stations is 1080i60, the actual content is coded as 1080p24 and can be viewed as such, using a process known as inverse telecine, since no information is lost even when the broadcaster (as opposed to the receiver) performs the 3:2 pulldown.[11]
[edit] Blu-ray DiscBlu-ray Discs are able to hold 1080p HD content, and most movies released on Blu-ray Disc produce a full 1080p HD picture when the player is connected to a 1080p HDTV with a HDMI cable. However, the Blu-ray Disc video specification only allows encoding of 1080p24 signal, and not 1080p50 or 1080p60
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