Thread: Hd Bandwidth ?
View Single Post
Old 06-05-2008, 20:11   #7
Losttheplot
Guest
 
Location: Wheres my hat?
Posts: n/a
Re: Hd Bandwidth ?

Quote:
Originally Posted by SMHarman View Post
HD
720p = 1280*720 = 921,600 Pixels
1080i = 1920*1080 = 1,382,400 Pixels
SD
720*480 = 345,600 Pixels < for information only - US format
720*576 = 414,720 Pixels

1382400/414720 = 3.333 times more data in an HD image
Transitions, encoding level of action will then also impact the size of the file etc.
Also bear in mind most of the SD is variable bit rate (VBR), whereas the BBC HD will be constant bit rate (CBR) of around 18Mb/s.
I dont know what Virgin use for their HD VOD bitrates, but the SD VOD was done at 2.9Mb/s (CBR) from memory.
  Reply With Quote