The ATSC standard (the thing that tells us what "HD" is) has no specification for 720i. 720p only exists because 1080p is too bandwidth-intensive for over-the-air broadcast, so they came up with a lower-bandwidth solution.
there is interlaced, and progressive video for any resolution. The reason most TVs dont have them though is because 720i isnt a media standard. i could go off and make a video thats 200i if i wanted to with a video encoder, but why should i?
there is interlaced, and progressive video for any resolution. The reason most TVs dont have them though is because 720i isnt a media standard. i could go off and make a video thats 200i if i wanted to with a video encoder, but why should i?
painguy1
Because it would make a smaller file? Load/steam faster for viewers on the internet?
There actually is 720i on really old TVs and other such devices but it is kind of useless since according to the current definition of "HD" it doesn't fit and 720p is just as easy to use
there is interlaced, and progressive video for any resolution. The reason most TVs dont have them though is because 720i isnt a media standard. i could go off and make a video thats 200i if i wanted to with a video encoder, but why should i?
sonic0491
Because it would make a smaller file? Load/steam faster for viewers on the internet? We're talking about TVs :P
540i is for PAL TV's and is the equivolent of 480i for NTSC-U. the reason the res is higher than NTSC is because the framerate in PAL (50fps) is slower to compensate for the higer resolution while NTSC uses a smaller res but higher framerate (60fps). Some pals run at 60fps aswell though but they are the minority. the reason for interlaced video is so the info can easly fit through your cable's bandwith or w/e u use. streaming 1080p through cable can be a pain. thats why most have 1080i as a limit. thats y inorder to stream HD video from a video game console u need a better cable. those cables have a higher bandwith to support the data that is sent through. sry for my grammer. i just woke up and went running for an hour & half. lol
It's simple math. Let me show you what i mean. 480i = standard definition 480p = enhanced definition 1080i, 720p and 1080p = high definition Okay. i stands for interlaced, so only 1/2 of the lines appear at any given time. They alternate frames, between odd numbered lines and even numbered lines. Of course this is happening too fast for the human eye to see. You really only notice this with sporting events where items are moving very fast, like hockey pucks or soccer balls will look blurry if you pause live games. That's because the odd numbered and even numbered lines are one frame (1/60th of a second) apart. p, on the other hand, stands for progressive. A progressive scan uses all the lines all the time. So 720p shoots 720 lines of resolution all at once. 1080p shoots 1080 lines all at once. 1080p is very demanding on systems, that's why most cable companies won't broadcast in 1080p. To determine the true resolution and compare them on an even basis, whenever you see an i, divide the resolution by 2. That's how many lines are coming through at any frame rate. So 1080i means 540 odd lines are coming across, then 540 even lines. You could shoot a video in 720i, however, the resolution would not be good enough to be called "high definition". 720 / 2 = 360. So 720i would fall somewhere between standard and enhanced definition. Since it's not considered "high definition", there's absolutely no reason to broadcast in 720i at all.
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