video & live streaming

What’s The Difference Between 4K And 8K?

Video resolution refers to the number of pixels, a display device (i.e. TV, PC monitor, laptop, tablet, and even smartphone screens), could be displayed in each dimension. In general, the resolution is quoted as width × height, such as “1920×1080”, where 1920 suggests the width and 1080 suggests the height that the display could be transformed in pixels. Most popular video resolutions are 1080p, 2K, UHD, 4K, and 8K. Although 4k and 8k both are classified as ultra-high-definition television (UHDTV) resolutions together, they possess their own unique features. Therefore, before we find the difference between 4K and 8K, let me explain what is 4K video resolution and 8K video resolution?

The articles “What’s the difference between 4K and 8K?”, explain the basics of video resolution, 4K and 8K resolution and also highlights how they are different from each other.

What is 4K resolution?

4K also known as Ultra HD (UHD), is a popular display resolution today. We know that resolution simply is the number of pixels a display has in the format of length x width. 4k signifies a horizontal display resolution of roughly 4,000 pixels.
The Digital Cinema Initiatives (DCI), a group of motion picture studios that creates standards for digital cinema, defines 4K video resolution as 4096 x 2160. Movie projection industry also uses this DCI 4k. However, monitors, usually labeled as 4K, have a 3840 x 2160 resolution. The same applies in the case of television and consumer media. Modern GPUs today support 4K/Ultra HD (UHD) output, though a quite powerful graphics chip is required to play games in 4K which is why most gamers prefer running at 1080p resolution.

What is 8K Resolution?

Logically 8K would be the double resolution of 4K, but interestingly, that’s not the case. 8k is also termed as UHD-2. At the moment, it is the highest ultra high definition television or UHDTV resolution. 8K implies to horizontal resolution of 7,680 pixels and vertical resolution of 4320pixels. So it forms the total image dimensions of 7680×4320. 8k resolution is in fact, 16 times the pixels of HD and 4 times the pixels of 4K. Hence, 8K equates to 7,680 × 4,320 or 33 million pixels.
To easily conceptualize it, let’s put it this way- when four 4K TVs are placed in a four-by-four grid, that’s a lot of pixels. That is why 8K can unquestionably be noticed when up close or on larger displays.

These days, manufacturers are starting to announce the availability of their 8K models. Even some time ago, there was little 8K Ultra HD resolution content to watch at home. But gradually this scenario is changing. Only in November 2017, video-streaming site Vimeo added support for 8K, but now it already has more than 6,000 videos tagged as 8K. NHK has made a permanent channel after launching a test channel for showing 8K content in December 2017.

4K VS 8K: What’s The Difference Between 4K and 8K?

The 4K and 8K video resolutions have some noticeable technological differences. They are very different in terms of resolution, frame rate, audio channel, broadcasting, and viewing angle. Here’s an overview of the basic difference between 4K and 8K video resolution for your convenience.

In Resolution

Well, a horizontal resolution of 7680 pixels and a vertical resolution of 4320 pixels refers to 8K UHD resolution. On the other hand, a horizontal resolution of 3840 and a vertical resolution of 2160 means 4K UHD. Therefore, the 8K UHD has two times the horizontal and vertical resolution of the 4K UHD. In general, the 8K UHD has 33.2 megapixels, while 4K UHD has only 8.3 megapixels.

In Frame Rate

Frame rate refers to the number of frames or images are displayed per second in a display device. It is closely related to video quality and widely used in synchronizing audio and pictures. It is said that the higher the frame rate is, the more natural the output (video quality). Well, the 8K supports frame rate up to 120 Hz progressive in contrary the 4K is only at 50 to 60 frames per second (FPS).

In Audio Channel

8K and 4K are very different in supporting audio channels. For 8K Ultra HD, it supports 22.2 audio channel, while the 4K Ultra HD supports 5.1 audio channel. In addition, with the 8K user may experience the three-dimensional super stereo.

In Viewing Angle

By viewing angle we mean the maximum number of angle that audience can view with acceptable visual performance on a monitor or a display device. It is an important feature that impacts viewers experience of watching. In terms of viewing angle, 8k support a 100-degree horizontal viewing angle while 4K offers a 55-degree viewing angle. 8K allows more visual angles in compare to 4K.

In Broadcasting

High-Efficiency Video Coding (H.265) should allow streaming 4K content with a bandwidth of 20 to 30 Mbit/s. In 2013, a transmission network’s capability to carry 8k resolution was restricted by internet speeds and depended on satellite broadcast to transmit the high data rates. This demand will presumably drive the adoption of video compression standards and place notable pressure on physical communication networks in the near future.

According to Wikipedia, Host Broadcasting Services has stated that at least 75% of the broadcast cut on each match would come from 4K cameras (covering the majority of main angles), with instant replays and some camera angles being upconverted from 1080p sources. The 2018 FIFA World Cup was the first FIFA World Cup in which all matches were produced in 4K. Experimental transmissions of the 8K resolution were tested with the 2012 Summer Olympics.

Let us now look at the differences between 4K and 8K and their specifications:

Specifications 4K 8K
Pixels -4k Ultra HD displays have a pixel count of 8 million or 8 megapixels. -8k sports 33 million pixels or 33.2 megapixels.
Resolution -3840 x 2160 pixels for Ultra HD television, or 4096 x 2160 pixels for digital cinema.
-Four times of the resolution of Full HD.
-For digital cameras, 4k resolutions are 4096 x 2160 pixels.
-Horizontal resolution of 7680 pixels and a vertical resolution of 4320 pixels.
-Sixteen times the resolution of Full HD.
-For digital cameras, 8k resolutions are 8192 x 4320 pixels.
Frame Rate 50 to 60 frames per second (fps) -120 frames per second (fps)
Audio Channel -Audio channel for 4K Ultra HD is 5.1. -Audio channel for 8K Ultra HD is 22.2.
-Users can experience the Super stereo via 8K TV in the near future
Viewing Angle -55-degree viewing angle 100-degree viewing angle available in 8K.
Allows you to watch videos via more visual angles.

The current aspects of 8K Resolution

Well, technologically the 8K resolution is undoubtedly superior to 4K. However, as 8K is still a new technology, it needs a process of widespread acceptance and adaptation. Here are some important points to be considered. As 8K is a new technology and yet to be accepted in the market, you may find a very few 8K video contents. Even, due to equipment i.e. Camera restriction or limitation, it’s hard to create video contents fit in 8K. And, even 8K contents as well as display monitor, could be very expensive. In addition, video file size also a matter to consider. The large size of an 8K video could be a big obstacle for hard disk capacity as well as for bandwidth.

Conclusion

To conclude, we can safely say that 8K display resolution is the successor to 4K resolution and is definitely superior. Both 4K and 8K, the two Ultra HD formats, can provide super vivid image and excellent visual sense. It is, however, a luxury for ordinary people to purchase a 4K or 8K UHD TV. It is also difficult to get various contents which are fully compatible with such high-tech products. But at this point, we can still foresee a future where 8K TVs will be the standard resolution for big-size TVs, despite their limitations.