IEEE Future Directions
Related Articles
HDTV was considered to be amazing, the real thing. In just a few years (HDTV started around the change of the century) HDTV has become a low resolution choice, 4k is now leading. From a user perspective what matters is the screen and it is easy to understand that cramming 4 times more pixels onto a screen should be somewhat difficult.
Yet, television is not a television set. It is a full blown value chain moving from capturing the images to transport them, storing them at various places and eventually viewing them on a screen. Actually, it affects an even broader area: did you know that because of the increased resolution provided by 4k new types of make up had to be invented to mask skin imperfections unnoticeable on HDTV but visible on 4k?
The sensor part (image detection) is actually not a big problem: thanks to the improvement in electronics we now have sensors available at consumer market price point that exceed 8k resolution (32 Mpixels, let me brag about my new camera that has a 47+ Mpixel sensor…). The microprocessors that have to process the data coming from the sensors are also up to the task, no problem there.
Transmission is a different story. If one would like to really have 4k quality, with a 12 bit color space (my camera has up to 14 bit color space!) one would need transfer rate of 1.6GB per second. Using compression scheme one can go down to 144MB per second (accepting a very limited loss in quality) and even further down to 15 and 10 MB per second (and obviously at these compression level there is significant loss).
If you want to transmit 8k resolution you need to multiply by 4 those rates (roughly, when compressing, particularly at high compression rate, the multiplying factor may be lower).
Current data transfer rates are not good enough for 8k and the industry has been working to come up with a standard supporting the required transfer rate for storing the video. Now this standard has been published (end of January 2018), UFS 3.0, supporting transfer speed up to 23.2 Gb per second (2.9GB per second) on two lanes. This kind of transfer rate can support 8k resolution. Notice that the big network and the last mile has not been designed for this kind of transmission capacity and massive compression will be required (as it is the case today for 4k, by the way). However it is important to preserve the quality in the storage of video at the source so that any rendering that may be required can be made on a very high quality video.
