Sigma Designs

Technology Briefs

4K: Coming Soon to a Home Near You?

Walk through a store featuring home electronics, and you will see 4K TV (also known as Ultra-High Definition or UHD) everywhere. The trend is definitely moving toward larger screen size (60” and up) in the home, and from a consumer electronics point of view, it would seem that the conversion from 1080 to 4K is complete. However, as with previous transitions in TV technology such as the implementation of 1080i/p, which took more than a decade to become truly mainstream with regard to consumer programming availability on broadcast, cable and IPTV, the move to widespread content available in 4K will take time. Many operators have already started testing 4K broadcasts, primarily for sporting events, and given faster replacement cycles for TV sets and intense competition among service providers, 4K is not too far in the distance.

Digging a bit deeper into the technology, it is important to remember that UHD goes beyond just additional pixels—this emerging specification includes a set of resolution, color range, and connectivity improvements. Operators considering broadcasting content at 4K resolution will need to make a series of decisions which revolve around cost of bandwidth and cost of equipment.

UHD goes beyond just additional pixels—this emerging specification includes a set of resolution, color range, and connectivity improvements.

What are the benefits of 4K?

The most immediate benefit of the UHD format impacts large TVs (40” and up) where today’s HD (1920×1080) resolution does not eliminate the perception of pixelization. The visual impact gained from encoding UHD content at 10-bit color depth versus 8-bit is also beneficial, given the increase in color range with negligible impact on stream bandwidth.

What about frame rate? As usual, movies will be broadcasted in 24 fps, sports, news and other live broadcasting events will be in 60 fps. But watching this content on a large display will also require a frame rate conversion to 120fps to make sure that the blur and other artifacts on the LCD display can be removed with higher frame rate.

Finally, there is content streamed directly from the Web. In this world, bandwidth is free but there may not be enough of it. It is reasonable to expect that every sort of 4K content will be found somewhere on the Web. However, only formats that can stream reliably at the data rates commonly delivered to subscribers by their ISPs today will dominate.


As in the case of HDTV adoption, we are likely to see an evolutionary process in utilizing the various capabilities of the UHD spec, constrained by economic realities. For the foreseeable future, TV systems deploying UHD will find the best set of tradeoffs by supporting HEVC encoding in the Main 10 profile at up to 30 frames per second for film and generic content, or 60 frames per second for sports and other fast-motion content.

Sigma Designs offers a full range of 4K chipsets supporting up to 4Kp60 for smart TVs and set-top boxes; our solutions are used by leading TV manufacturers including VIZIO, ROKU and Sharp.

Filed under: 4K / UHD, Set Top Box, Smart TV, Technology Briefs