4K Streaming v. 4K Disc: Bit Rates and the Future

Physical media had been the only choice for so long that it almost seems strange how quickly it is vanishing. Consumers were finally able to watch movies at home with Betamax and VHS in the 1970s. Then, DVDs in the late 1990s and 2000s became the dominant media for video and pretty much stayed that way forever. Blu-Ray came out in 2006 and regularly sells less than DVDs today. 4K UHD is still fairly new, but the adoption of the media is slower than the releases of both DVD and Blu-Ray. Signaling a significant decline in consumer demand for home media.

The internet gave way to streaming and allowed for a new means of watching movies at home other than physical media. Physical media has been declining in market share since the dawn of Netflix and competitors in the streaming market. When you watch a movie at home on a Saturday night is it through a streaming service like Netflix, Prime Video, or HBO Max? It would certainly not be a surprise if so, as streaming is now the dominant form of television viewing in the United States.

Streaming allowed most television buyers in the United States to finally benefit a bit more from their nice screens. Most movies and shows on the major streaming services are at least offered on HD and offer a vast amount of 4k UHD content. Even though 81% of US households have HD televisions and 44% have 4K TVs, most physical media consumers never really even bought onto the HD Blu-Rays. Siding instead with the SD DVDs for most of Blu-Rays run. 4K UHD disc sales would almost certainly be higher if not for streaming competition, but consumers already appeared to be largely okay with lower quality resolutions.

Fewer people are opting for the 4K UHD disc platform than prior platforms, but film fans trying to get the best picture on their 4K TVs still have to consider the platform for adding to their collection. Streaming services and digital stores like Apple combined have almost every show or movie you could ever want to watch, but if you want the best in image quality then UHD discs are often the slightly superior choice.

Is the slightly superior worth the cost? Entrance into the physical media space is getting cheaper with the arrival of the PlayStation 5 and Xbox Series X. Physical media has always had a close connection with the videogame console generations by gaining entrance into a household they were often most families first player capable of any media. The PS2/XBOX with DVDs and the PS3 with Blu-Rays were able to enter homes where stand-alone devices largely fail, only appealing to die-hard fans.

The cost of digital store purchases is often much lower than for physical media regardless of the marketplace. For instance, iTunes regularly has new release 4K movies available for anywhere from $10 to $25, compared to the $25-35 cost of 4K Blu-Rays. Is that difference in price worth it to own a piece of physical media in your hands?

Admittedly you may not own your digital movies – but you really only technically “license” the right to watch a DVD in your house. A fair worry would be on the future of the digital marketplace you chose to collect your movies, but services like Apple and Amazon seem like fairly safe bets to be around a while. At least, probably longer than the past couple of video generations of SD and HD – which caused a great many DVD and Blu-Ray collectors to have to abandon their collections in favor of an advanced option. Apple and Google even go a step further by future-proofing your collection with free upgrades to the latest 4K option available.

Price and convenience are safely in favor of streaming, but when it comes to video quality the consensus is that disc is still king. The enhancements might be more difficult to perceive and require a larger screen to truly make out a lot of variation, but there is a significant amount of additional data read from a disc than streamed through an internet connection.

Bit rate refers to the number of bits used per second to represent a continuous data stream of video or audio. Higher bit rates confer more data being processed at any second. This added data is essentially more of the image at any frame.

Streaming services use compression to shrink large 4K media files so they can be obtained through internet speeds owned by most consumers. The bit rate will correspond similar to how fast your internet connection runs, which means our current streaming services are limited by the quality of the speed our internet provides.

Take a look at the various bitrates associated with popular streaming services. You can also check out this link to see the breakdown of peak and average bit rates achieved for various films on streaming services.

Apple TV just blows away the streaming competition with 56% higher bit rates than the next closest service with 26 Mbps (which means you will need internet speeds at least that much). I’ll contest that movies purchased through iTunes almost always look sharper than other stores, but the difference between iTunes and 4K Blu Ray is still extremely large. 4K Blu Rays have bitrates 500% or greater than iTunes with a whopping 80-120+ Mbps.

To achieve a lower bit rate for more fluid streaming, these services have to remove the least noticeable data of the image by tossing out minor pixel detail. The lower pixel detail leads to a softer image with less color definition. Notably, more chaotic imagery on a screen will be the easiest scenes to tell a difference where added bit rate may be helpful.

You are undoubtedly getting a more detailed image from the disc with a much higher Mbps, but it is also important to note that it takes a large amount of compression to even get a 4K film onto a disc. A truly lossless or uncompressed 4K video would require a bit rate of 7,166 Mbps. The jump from 26 Mbps to 120 Mbps is pretty large, but still, nothing compared to how much detail was already absolved from the image.

The detail added to an image from higher bit rates is also what allows 4K disc to have much more detailed sound. Discs can achieve lossless audio streams with perfect detail, in other words, zero compression. The bit rate on 4K discs averages around 3-5 Mbps with peaks hitting 10-15 Mbps, while streaming is usually only around 192 Kbps. Streaming with Dolby Vision does require 384+ Kbps so streaming is improving with additional technological gains.

These technological gains are primarily where streaming shines. 4K disc has limited room to improve and with adoption rates, we may never get another disc format again, and even if we did it would require a large upfront cost to buy the new media. Streaming bit rates have been increasing drastically over the past decade. Netflix went from 1-2 Mbps for 720P, to 3-7 Mbps for 1080P, and now around 16 Mbps for 4K content. With Apple already at 26 Mbps we may see streaming capabilities increase and get closer to disc bit rate over time with internet speeds increasing and 5G roll out.

Streaming isn’t incentivized to add additional bit rate requirements beyond what their install base is expected to have the necessary speed needed for the streaming movie. In fact, a lot of work is done today on the codec side. HEVC is the current standard for both streaming and disc and provides a range of benefits over older codecs. Remember the crushed black scenes from the final season of Game of Thrones that the internet was upset about? Old codec. That episode would have looked much better on most other streaming services.

HEVC allows for a more efficient compression that is claimed to result in 50% bit rate savings for equivalent picture quality over the older MPEG-4 codec. Now, that does not help streaming much in this debate – both disc and streams use the newer codec. The difference comes later with the codecs waiting in the pipeline. Notably, the successor to HEVC, VVC is developed and is currently in the licensing stage – so it is well on its way to streaming services. For physical consumers, the additional codec will require new chips.

The new VVC codec claims a similar improvement to HEVC of 50% increases in bit rate savings for equivalent picture quality. It is not clear yet what physical players will be needed for this new compression codec, but clearly, the effort of these compression codecs is done for streaming. It is not outside the realm of possibility that advancements in compression codecs can make the bit rate comparison between disk and streaming null in void – streaming could be so well compressed that it may not need the high bit rates of disk to achieve the same picture.

Internet speeds are getting faster, up over 500% since 2007. COVID accelerated the demand and created a potential incentive for increased governmental assistance in getting internet connectivity to more rural Americans. The people that do have broadband internet access are now averaging around 100 Mbps service, more than enough for much higher bit rates over streaming. Streaming services may be able to get close to 4K disc quality now, but at the behest of most of America not able to ascertain the required speeds – not to even mention how fast you may hit your provider’s data cap.