Why is 1080p and 1080i




















For example i and p. From the outside, little to nothing is revealed about their attributes or differences. High-definition HD refers to a screen resolution of pixels wide and pixels high hence the use of "". This means that both i and p have the same resolution. Read on to find out. The first thing to note is that the letters in i and p refer to which raster scan technique is used.

A raster scan is simply how an image is reconstructed onto a display monitor. These refer to two distinct methods of producing an image on a screen at x resolution. Imagine your TV screen as rows of pixels. How fast the pixels are refreshed is referred to as the refresh rate. Most TVs and display monitors work at a refresh rate of 60hz 60 refreshes a second. For the video display to work, each pixel in a digital screen must be refreshed fast enough to perceive it as motion even though the screen is technically just flashing individual images.

An interlaced scan produces an image by displaying the odd and even rows of pixels alternatingly. Yep, that's right, it's making stuff up. Or, if you want to argue it differently, it's manipulating the image so there's no artifacts, at the expense of absolute resolution. Don't worry, though, TV processing has gotten really good at this and usually does a lot more than just "averaging" so the result is rather seamless.

Now this is where an argument about p -- real p -- becomes worthwhile. A full frame-per-second p video would be awesome. Not because it's a higher resolution than i, but because it's a higher frame rate and not interlaced , so motion will be more detailed.

However, it's highly unlikely most people would ever see a difference. Compression artifacts in the source or edge enhancement in the display are far more detrimental to the image than deinterlacing. Reducing either of those two factors would have a bigger effect on the image. So with full p, the subtle increase in motion detail isn't likely to be noticed. Movies and the beauty of Movies are, and will be for the foreseeable future, 24 frames per second.

Sure, James Cameron , Peter Jackson , and even Roger Ebert want to up the frame rate, but that's going to be an uphill battle. When it comes down to it, people equate 24fps with the magic of movies and higher frame rates with the real-world reality of video. Changing people's perception is a lot harder than twisting a dial on a video camera.

Note that I'm not arguing for or against higher frame rates here. Maybe in a future article. As we've discussed, this is actually less than i.

This is most often due to other factors, like compression. At least, not yet. It maxes out at wait for it i! Funny how that works. Those of you astute at math will be wondering: how do you display 24fps on a 60fps display? Not well, honestly.

The trick is a sequence of frames colloquially referred to as , from pull-down , the method used. When shown on a 60Hz TV, they're arranged in a pattern, like this:.

The first film frame is doubled, the second frame is tripled, the third is doubled, and so on. Although this means 60Hz TVs can operate with minimal processing effort, it results in a weird judder due to the bizarre duplication of frames. This is most noticeable during horizontal pans, where the camera seems to jerkily hesitate slightly during the movement. Ideally, you'd be able to display duplicate frames without the sequence. Galaxy Buds 2 Best Movies on Netflix.

Wait, what about 4K? Tech companies are blaming the chip shortage on the maker of your calculator. How to level up fast in Call of Duty: Vanguard. Google One subscribers now have enhanced photo-editing tools on iPhones.

So, accordingly, the horizontal lines of pixels in each field are captured and displayed with a one-line vertical gap between each, eventually forming an interlaced display among all the lines. Most HD channels on satellites and cable broadcasts use i to illustrate lucid and natural displays.

Contrastingly, p is a set of pixels horizontal lines and pixels vertical lines on the screen to deliver a high-resolution display. Speaking of which, p made its trademark in the late s following the high-definition image formats for a television production. This non-interlaced display captures all the pixels across the horizontal screen and pixels down the vertical screen at the same time. Eventually, a p screen displays a total of 2.



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