What is 1080p?

1080p means 1920×1080 pixels of resolution; it is also known as Full-HD, FHD, WUXGA and BT.709, and applies to TVs/displays/media resolution in which the “p” means that the resolution is “progressive” which means that there are truly 1080 vertical lines.

1080p implies a display/content aspect ratio of 16:9 and represents 2M pixels (2073600 to be exact). FHD/Full-HD is the other most-used term to market this resolution. As a reminder, “HD” was introduced as 1280×720 pixels, also known as 720p.

1080p only describes the resolution and does not imply the refresh rate for displays, or the frame rate for video content. These details are encompassed in different standards of broadcasting or video-encoding, that generate a 1080p resolution image.

1080p was and still is a standard for many things, including Blu-Ray content, Televisions, Computer screens and Mobile devices displays – just to cite the most popular ones. 1080p and FHD/Full HD are used interchangeably in “technology” communication materials, and they mean the same thing.

Can content that is not 1080p be played back on a 1080p display?

It’s possible. Every display system has a “native” resolution, which is its number of pixels. Any media content can be resized and filtered to fit any native resolution.

If the display resolution is superior to the content resolution, the image quality won’t be improved by much. There are ways to slightly enhance the image during the up-scaling phase, but it won’t be equal to content created for the target resolution.

If the display resolution is inferior to the content resolution, the resizing will yield a best-possible image quality for that display. This is down-scaling. Both up-scaling and down-scaling are part of video scalers.

Although most good video players have some image downscaling capabilities, not all of them can upscale an image to a resolution that was possibly not in existence when they were manufactured. For example, many Blu-Ray players were sold well before 4K became a standard. Therefore, they have no awareness of that resolution, and cannot upscale to it.

What’s the difference between 1080p and 1080i?

1080i and 1080p can cause some confusion, although the use of 1080i is on its way out. “i’ stands for “interlaced” (and “p” is “progressive” as we said earlier).

The difference is that 1080i displays have only half the vertical resolution of 1080p, so ~540 (actual) lines. They can display 1080p content by “interlacing” the images lines, every other frame.

This results in a slightly better image than having 1920×540, but it is noticeably not as good as true 1080p. This interlacing technique was widely used when analog displays were very common and yet unable to physically achieve 1080p resolution. 1080i isn’t used much these days, but you may bump into it from time to time.

Hubert Nguyen
Categories: Photo-Video
Tags: display