1080p, Full HD, Resolution ...question

[wrenaudrey]

Can someone please answer my question/query that i am really confused about and cannot get a straight forward answer anywhere.

"Full HD"- When you have a monitor/TV that has 'something' by *atleast-ATLEAST* 1080 (this "by 1080" is what im exaggerating) does this always mean it is "Full HD"? For example a monitor's resolution is 2560 x 1600, does this mean its Full HD?

 

[gary1]

If a monitor has a 2560x1600 resolution, it is beyond Full HD.

 

[wrenaudrey]

That did not answer my main question though. Is a monitor/tv Full HD if the resolution runnig down the side is atleast 1080?

 

[gary1]

Yes. The threshold for Full HD is 1920x1080. Anything above is full HD.

 

[wrenaudrey]

So does this mean for a monitor/tv to be atleast capable of 720p the resolution running down the side has to be atleast 780?

 

[gary1]

Where are you getting 780?

720 is 1280x720. 1080 is 1920x1080. 480 is 640x480.

 

[wrenaudrey]

Sorry typo, meant to be 720, sorry. But anyway, that makes it so clear now.
But another question, on handheld device like an iphone(4/4s), how is it capable of 720 and even up to 1080p playbacks if the screen on has 960x640 resolution?

 

[gary1]

You got me there. I'm assuming it cannot play full hd back, and downgrades it.

 

[jaguarskx]

Generally speaking, if you have a 2560x1600 or 2560x1440 monitor and you watch movies/videos on it you can do it in two modes; full screen and windowed mode.

Becasue 2560x1600 and 2560x1440 resolution is above Full HD 1080p (1920x1080), playing a video in windowed mode will naturally not fill the entire screen. When you play it back in full screen mode you are basically stretching the movie/video to fit the monitor's resolution. The more you stretch it the worse it will look.

Stretching a movie to larger than it's normal resolution results in something called video interpolation which basically estimate how the entire movie should look. It's actually a bit more technical than that. Therefore, stretching a HD movie onto a 2560x1440 monitor will result picture quality that is a bit fuzzy. That's because 2560x1440 has almost 80% more pixels than 1920x1080.

DVD movies (1280x720) will look worse when you stretch it to fit a 2560x1440 monitor. That because it will be stretched to 4x the original size. Again that's due to video interpolation.

As an analogy, let's say a hand knit wool blanket represents the video. When playing back the video in full screen mode you are basically stretching the video. When you stretch out a knit wool blanket, the wool yarn starts to separated from each other and small holes begin to appear. The more you stretch the blanket, the bigger the holes will be until you can see through the holes. That's basically what video interpolation is like.

 

[Dajoca]

Great Analogy jaguarskx.

I always struggle to explain to people that you can't enlarge an image without some loss of quality or other compromise in quality and your method explains it very nicely.

Thanks.

 

[mbrembati]

DVD movies (1280x720) will look worse when you stretch it to fit a 2560x1440 monitor. That because it will be stretched to 4x the original size. Again that's due to video interpolation.

Agree on everything but objection here. As 2560x1440 is exactely 2x vertical and horizontal resolution of the 1280x720 movie, every single pixel of the original movie will be represented by a 4 pixels square (2x2) on the 2560x1440 screen, so no loss of quality in this case, just the same result as watching it on a 27" native 1280x720 screen.

 

[ssddx]

true, any loss in visual quality is likely to be comparable to watching it on a larger screen. with the move towards 1080p video though the point is still valid as 1080p is not an even multiple.

 

[dmobbjr]

The iPhone has 720p and 1080p video recording not playback. If you copy the video a computer with an HD screen, you can watch in HD.

 

[cjl]

Agree on everything but objection here. As 2560x1440 is exactely 2x vertical and horizontal resolution of the 1280x720 movie, every single pixel of the original movie will be represented by a 4 pixels square (2x2) on the 2560x1440 screen, so no loss of quality in this case, just the same result as watching it on a 27" native 1280x720 screen.

Ideally, the playback would be doing an upscaling and interpolation, not simply a pixel doubling. An upscaled image should be substantially better than a pixel doubled image, though worse than a native image at the monitor's full resoultion.