Will UHD Blu-rays have to do without Dolby Vision on Xbox Series X?
The count of the number of sleeps left has undoubtedly begun for those who have pre-ordered one of Microsoft’s or Sony’s next-gen consoles. Many will rejoice at the promises of higher frame rates, ray tracing, better sound, faster loading times, more details and higher resolutions.
Part of the group planning to connect an Xbox Series X or S to their television may also be interested in the promise that Dolby Vision will be supported for games. This HDR standard was already available for the Netflix app, but this is not the case with the UHD Blu-ray player of the One X and S. Now that more and more UHD Blu-ray films with Dolby Vision are released in addition to HDR10 and now that Dolby Vision was prominently announced as a feature of the Xbox Series X and S, many people expected or hoped that Dolby Vision would also be available in combination with the 4k discs would be supported. However, it seems that is not the case.
There are a number of reasons for this, with Dolby Vision’s ‘split personality’ probably playing a role. What about the two different implementations of this HDR standard in the market, what about the Series X and S and what does it mean for users?
Dolby Vision on Microsoft’s next-gen consoles
In September, Dolby Labs and Microsoft announced that the Xbox Series X and Series S are the first and only next-gen consoles to support Dolby Atmos and Dolby Vision. In an official announcement of the Series S console, Microsoft said that the Dolby Vision will be available for streaming apps such as Netflix and Disney + from the release of the two consoles, but that the standard will not be available for games until 2021. What exactly the latter will look like is still unknown. For example, it is not yet clear which games will support it. It will probably only be a handful of games in 2021, partly because Dolby Vision, unlike HDR10, is not a free, open standard. Also, only certified companies can perform the necessary color correction and HDR10 largely achieves the same effect.
Now that it is clear that Dolby Vision will be available for streaming apps and games on the two new Xbox consoles, one question remains: can the Series X, as the only one of the two Xbox consoles with a disc tray, also support UHD Blu? -rays with Dolby Vision?
Playback in itself will not be a problem, because HDR10 is also always present on the 4k discs with Dolby Vision. But whether the latter standard is also supported for playback is the question. It seems not, claims John Linneman of Digital Foundry . This medium has had access to the Xbox Series X for some time and Linneman says that as far as he can determine, there is no Dolby Vision playback with UHD Blu-ray.
We were able to determine this with a fair degree of certainty on the editorial floor, by connecting the Series X to an LG CX OLED television and using a test disc called Spears & Munsil. The menu shows the message that the player or TV does not support Dolby Vision. The CX supports Dolby Vision, so it’s clear that this is where the lack of support lies with the player, i.e. the Series X.
This may be possible with an update to the Blu-ray app that is required for playing UHD Blu-rays on the console. We have not yet been able to test more UHD Blu-rays, but in any case, based on this single disc, the conclusion that Dolby Vision is not supported by the UHD Blu-ray player seems justified.
Two profiles of Dolby Vision
Probably one of the main reasons that Dolby Vision does not seem to be supported with UHD Blu-rays in the Series X is because the HDR standard seems to be implemented in the same way as with the Xbox One. This previous-generation console received Dolby Vision support for the Netflix app in 2018, and it appeared to be coming for UHD Blu-ray playback, but a Microsoft spokesperson was quick to point out that previous confirmation of this was flawed. . Since then it has been quiet from Microsoft regarding the support of Dolby Vision in combination with UHD Blu-rays via the disc tray. This support hasn’t materialized to this day, and for now it looks like it won’t be any different with the Series X.
This may be due to the specific implementation of Dolby Vision on the Xbox One and the Series S/X. This is the so-called low-latency variant of Dolby Vision, compared to the regular standard implementation. In the standard implementation, which is included in the vast majority of televisions with Dolby Vision, the television’s hardware does most of the work. The television can feed its exact capabilities such as peak brightness, white point of the screen and color coordinates into the built-in Dolby Vision mapping engine , so that using all relevant capabilities and parameters, the tone mapping for the scene-by-scene or even the frame-by-frame analysis can be performed.
With this, the TV achieves the most accurate possible representation of the Dolby Vision color correction of the content. On the other hand, with the low-latency version of Dolby Vision, the source device mainly does the heavy lifting and a lot of decoding is already done before the signal goes to the television. What does happen is that the EDID data is sent from the television to the source, on the basis of which the tone mapping takes place.
Meaning of the low-latency variant of Dolby Vision
Because the latter does not happen internally in the television and this data is less complete, the display is also less accurate , according to Vincent Teoh of HDTVTest, for example . Also on Reddit you can find the necessary findings of users who complain about the Dolby Vision experience on their Sony OLED televisions, which would be weaker than when applying the HDR10 standard, for example.
It is also more often mentioned that there is posterization in the parts of the image that are almost black, with rather hard, unnatural transitions visible between the different dark color tones. The reason why Sony TVs are mainly complained about in this context can easily be explained: Sony is about the only television manufacturer to date that has equipped its televisions with the low-latency variant. To this end, Dolby worked with Sony to get Dolby Vision on a number of Sony televisions from 2017. At the time, this new Dolby Vision profile was not compatible with quite a few source devices, such as UHD Blu-ray players or the Apple TV 4K. Gradually, these types of devices received updates so that they could still handle the Dolby Vision implementation on the Sony TVs. TVs from LG, for example,
It is possible that Sony is gradually moving away from the low-latency variant. A recent firmware update that enables 4k120 on Sony’s XH90 television now appears to support the TV-based variant of Dolby Vision, according to findings by Belgian tech journalist Eric Beeckmans , while previously it was the low-latency variant. Perhaps this is due to the fact that the XH90 is the first Sony TV to have the newer MediaTek MT5895-soc , so that the heavy lifting with regard to the calculations for the Dolby Vision display can now be done by the television.
Apart from the disadvantages of handling Dolby Vision at the source, it can also be less good news for owners of, in particular, relatively older televisions with Dolby Vision. Already at the official Microsoft announcement of the arrival of Dolby Vision for the Xbox One S and X, the company indicated that users must have a television that ‘supports the latest version of Dolby Vision’. By this, Microsoft refers to the low-latency variant.
LG indicated to tech journalist John Archer that its 2016 OLED TVs cannot handle the Xbox One’s Dolby Vision, even though these 2016 LG TVs do support the standard. LG indicated that users with these televisions should fall back on HDR10 for the Dolby Vision content on the Xbox One. LG televisions with Dolby Vision from 2017, 2018 and 2019 would be compatible. A simple update for these older televisions, as happened from 2017 to allow Sony televisions to handle Dolby Vision with, for example, UHD Blu-ray players, was probably not an option, because these first Dolby Vision televisions from 2016 not go beyond 4k at 30fps when Dolby Vision is displayed. And that differs from the Xbox One’s 4k60 output, whichaccording to Rasmus Larsen of FlatpanelsHD is unable to adjust this frame rate.
Microsoft’s choice for the low-latency variant of Dolby Vision is easy to explain. It is actually already in the name or designation of this profile. Because the heavy work does not have to be done by the television and the tone mapping has already been done at the source and the result is more or less ready to be sent to the television via the HDMI cable, it can be displayed without major delays. If the variant of Dolby Vision were used on TVs, there could be more latency. And that is especially a problem in games, especially with faster action games such as shooters.
HDR differences with the next-gen consoles
Sony has not disclosed anything about Dolby Vision regarding its PlayStation 5; as far as Dolby Labs standards are concerned, this console will probably only support Dolby Digital Plus and TrueHD for the various streaming apps and Dolby Atmos via bitstream for the version with the uhd blu-ray player. Then we are of course talking about the sound. In terms of HDR, it seems that the PS5 only supports HDR10, which will be the case for streaming apps, games and the UHD Blu-ray player. The latter also applies to the Xbox Series X, supplemented with Dolby Vision for at least streaming apps and gradually for games.
There also seems to be support for HDR10 +. At least, Chris Plante of Polygon previously wrote that a Microsoft representative has confirmed that the Series X also supports this hdr standard . More details are not known. Presumably HDR10+ will only be available for Amazon’s Prime Video app.
HDR10+ is a standard that Samsung in particular has put its weight behind. The company presents HDR10 + as a free alternative to Dolby Vision. They are both standards, the main difference with HDR10 being that they are based on dynamic metadata instead of static metadata. With a game or movie with HDR10, extra data is sent at the start, on the basis of which a number of properties are described, such as the maximum and average brightness level. However, this data is static; the same settings are used throughout the entire movie or game, and no in-between frame-by-frame or scene-by-scene adjustments are possible. The latter can be very useful, for example if there are alternately very dark or very light scenes.
The added value of Dolby Vision
Now it may sound like Dolby Vision is far superior to HDR10 and that the PS5’s lack of Dolby Vision is a serious loss. If you look at it on paper, that is a conclusion that may be drawn quickly. Where HDR10 assumes static metadata, a maximum of 4000cd/m² and a maximum of 10 bit color depth, Dolby Vision assumes dynamic metadata, a maximum of 10,000 cd/m² and a maximum of 12 bit color depth. However, there is currently no consumer television with a 12-bit panel and there are few televisions that offer a brightness of more than 1000cd/m². That’s only for some high-end LCD TVs; no OLED TV achieves that.
The difference between dynamic and static metadata can be a real advantage. With static metadata, scenes can be too dark or too light much sooner. Dolby Vision is often also better able to display colors more accurately or to make them stand out better. However, these kinds of benefits will usually only make a difference on high-end televisions that are also very capable of displaying HDR. Then we are talking about OLED TVs or expensive LCD TVs with full array local dimming , with the necessary individually dimmable zones.
Most users will have televisions of lesser quality, which support high dynamic range on paper, but are actually not well equipped for a good display with an enormous contrast between light and dark parts. These are cheaper LCD TVs. The fact that these are not ideal televisions for HDR means that the difference between HDR10 and Dolby Vision will probably be negligible in such cases.
Even with a high-end television, a good HDR10 implementation can work wonders, as games like Gears 5, Forza 4 Horizon and A Plague Tale: Innocence prove. The HDR10 display in these games, among others, is convincing, with light sources that contrast so brightly against the environment on OLED TVs that it almost hurts the eyes at times. That naturally raises the question of whether a Dolby Vision implementation can improve that in a clearly visible way.
Whether Dolby Vision will really make a difference in games in practice will also depend on how much value game makers will attach to it. It will be very important to Microsoft and especially Dolby Labs to put Dolby Vision as a big plus for the Xbox Series X, so that Dolby Vision will probably be the first to be supported in one or more games from Microsoft’s own studios next year.
The color correction process will therefore undoubtedly be done with due care in these first games, but in the past game developers have not always taken HDR seriously, with even pseudo-HDR implementations, as was initially the case in Red Dead Redemption 2 , which were rightfully labeled as fake HDR. That makes one wonder whether without financial incentives there will be really broad interest in seriously working on Dolby Vision support in games, on top of the broad support of HDR10 in games.