Apple’s “Extended Dynamic Range” Brings HDR to Non-HDR Displays

Wow, that&#x27;s crazy, it actually works -- just tried out the sample videos in QuickTime on my 2016 13&quot; MBP (P3 gamut, running Big Sur) and confirmed working.<p>Basically: if I set my display to ~75% brightness and open the video, the whites in the video are 100% brightness, <i>way</i> brighter than #FFF interface white on the rest of my screen.<p>But if I increase my display brightness to 100%, the whites in the video are the same as the interface white, because it obviously can&#x27;t go any brighter.<p>If I decrease my display brightness to 50%, the whites in the video are no longer at maximum 100% brightness, maybe more like 75%.<p><i>But</i> it&#x27;s also kind of buggy -- after messing around with system brightness a bit, the video stops being brighter and I&#x27;ve got to quit QuickTime and restart it again for effect. Also, opening and closing the video file makes my cursor disappear for a couple seconds!<p>I&#x27;m wondering if it <i>switches</i> from hardware dimming to software dimming when the video is opened and closed, and if that switch has to do with the cursor disappears. If it is, though it&#x27;s flawlessly undetectable in terms of brightness -- the interface white and grays don&#x27;t change <i>at all</i>.<p>Interestingly confirming it: taking a screenshot of the video while screen is at 75% brightness show massive brightness clipping in the video, since it&#x27;s &quot;overexposed&quot; in the interface&#x27;s color range. But taking a screenshot while screen brightness is 100% shows no clipping, because the video is no longer &quot;overexposed&quot; to the interface.<p>I&#x27;m just so surprised I had utterly no idea macOS worked like this. I&#x27;d never heard of this feature until now.

I wonder how a large organization does something like this successfully. Like you need your OS video driver team working with the application team and so on.<p>My impression is that PMing this is really hard. And then each of the other guys is going to have an opinion that this shouldn&#x27;t be done because it&#x27;s so rare, etc.<p>Something must be organizationally right for something like this capable engineering to have succeeded on such a barely noticeable feature.<p>I love it when products casually have cool things like this. Not quite the same scope but IntelliJ&#x27;s subpixel hinting option has each element of the drop down displaying with the hints that it describes. You don&#x27;t have to pick an option to see it. You can just preview it off directly.

It seems to me that Microsoft really makes no effort to improve subtle aspects of Windows and hardware integration. In fact, their OS is in such shambles and is a disoriented mess with respect to UI consistency. They introduced Vista, Metro, and now Fluent. Yet there&#x27;s almost no coherence and the UI is now a mish-mash of XP, Metro, and Fluent era elements. By the time they announce their next UI, you can bet you&#x27;ll now see yet another ingredient added to the jumbled soup.<p>It really is beyond belief that an organization with so many employees can fail to adhere to a uniform vision and standard and focus on correcting details.<p>I&#x27;m a life long Windows and Android user. But honestly, seeing articles like this and how smooth the UI on macOS and uniformly they apply new updates and UI changes makes me extremely jealous and resentful that Microsoft is so bad at something so basic.<p>Features are great, but users at their start point interact with UI first. They need to fix that before anything else.<p>Now they want to give you the option to run Android apps on Windows through emulation. This just going to create a bigger jumbled mess.

&gt; This EDR display philosophy is so important to Apple that they are willing to spend battery life on it. When you map “white” down to gray, you have to drive the LED backlight brighter for the same perceived screen brightness, using more power. Apple has your laptop doing this all the time, on the off chance that some HDR pixels come along to occupy that headroom.<p>This is a bit misleading. The backlight isn’t at a higher level than necessary for sRGB content all the time, just whenever any HDR encoded videos or EDR apps are open. When you open an HDR video you can see the highlights getting brighter as the backlight gets pushed.

I’ve had the XDR Pro Display since June, and use it primarily for dev. I just trusted Apple in their focus on this direction. Suffice it to say I am very happy with it.<p>What I like about conclusions of this piece is it points to how strategic Apple is thinking in its leverage due to the breadth of distribution of advanced hardware and software.<p>Apple is able to set entire new standards of expectation for customers that are _very_ hard for competitors to follow.<p>While competitors fixate on some single feature like night photo quality, Apple is also subtly chipping away at something like this.

When still talking about mixed SDR+HDR content on a HDR display having differently mapped whites, the article says:<p>&gt; it’s strange and new, and possibly unique to Apple.<p>But that is exactly how Windows 10 does it with HDR displays, too. So not really unique to Apple. To the article&#x27;s benefit, it did say &quot;possibly&quot; :)<p>I&#x27;m using Win 10 myself with an HDR display, and HDR white appears brighter than &quot;desktop&quot; white just like in the article photo.<p>There is also a slider in Win10 HDR settings that allows you to bring SDR&#x2F;&quot;desktop&quot; white up if you wish to oversaturate SDR.

This reminds me of a recent submission about Wayland colour management and HDR work: <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=25159592" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=25159592</a>.<p>In particular <a href="https:&#x2F;&#x2F;gitlab.freedesktop.org&#x2F;swick&#x2F;wayland-protocols&#x2F;-&#x2F;blob&#x2F;color&#x2F;unstable&#x2F;color-management&#x2F;color.rst" rel="nofollow">https:&#x2F;&#x2F;gitlab.freedesktop.org&#x2F;swick&#x2F;wayland-protocols&#x2F;-&#x2F;blo...</a> was linked which discussed how a wayland compositor would have to display mixed &quot;HDR&quot; and SDR content on the same display. This document even has references to EDR. Ultimately this would end up achieving a similar result as what&#x27;s described in the blog post here.<p>If you&#x27;re interested in the technical details on what may be necessary to achieve something like this, the wayland design document might be a good read.

I noticed this &#x27;extra bright whites in video&#x27; effect on my iPhone 12 just after upgrading. I had to go and shoot &#x27;normal&#x27; + HDR video of the same thing a few times back and forth to be sure I knew what I was seeing.<p>The first thing you think is, how was I OK with this terrible standard video to begin with? The HDR version just looks SO MUCH better and the standard looks so flat next to it. Like comparing an old non HDR photo with an HDR one.

&quot;On these non-HDR displays, Apple has remapped “white” to something less than 255-255-255, leaving headroom for HDR vales, should they be called for&quot;<p>What is the source for this? I don&#x27;t see any justification for this claim in the article. There are plenty of ways to implement this feature that don&#x27;t involve permanently throwing out dynamic range on all your SDR panels. I&#x27;m not even convinced from reading this that they aren&#x27;t HDR panels to begin with - the idea of an iPhone having a 9-bit or 10-bit panel in it isn&#x27;t that strange to me, and while that wouldn&#x27;t be enough for like Professional-Grade HDR it&#x27;s enough that you could pair it with dynamic backlight control and convince the average user that it&#x27;s full HDR.<p>Considering Apple controls the whole stack and uses a compositor there&#x27;s nothing stopping them from compositing to a 1010102 or 111110 framebuffer and then feeding that higher-precision color data to the panel and controlling the backlight. Since they control the hardware they can know how bright it will be (in nits) at various levels.

I just tested the sample file provided in the article at my Macbook with QuickTime, IIAN, and VLC. I can confirm the result in the article but it is Quick Time only. Colors in IIAN and VLC are not as bright as in the QuickTime.

Now browsers will have to be modified to support colors in excess of 255. Flashing ads will be brighter than ever!

The author is rightly excited about HDR, but could be slightly overstating its effect in some examples.<p>&gt; But at key parts of the story, certain colors eek outside of that self-imposed SDR container, to great effect. In a very emotional scene, brilliant pinks and purples explode off the screen — colors that not only had been absent from the film before that moment, but seemed altogether outside the spectrum of the story’s palette. Such a moment would not be possible without HDR.<p>I think the author knows that this is a special case of the effect where you limit color palette to some range of colors for a duration of the film and then exceed that range in places—no HDR in particular fundamentally needed to make this possible.<p>True, HDR can give a greater effect in absolute colorimetric terms when full palette is revealed, but the <i>perceived</i> magnitude depends on how restricted the original palette was prior to the reveal, and how masterfully the effect is used in general.

My favourite and most succinct comment on this is that “this one goes to 11”

Macs can also play HDR content on external displays, such as HDR televisions and projectors. This document lists Mac models supporting HDR: <a href="https:&#x2F;&#x2F;support.apple.com&#x2F;en-us&#x2F;HT210980" rel="nofollow">https:&#x2F;&#x2F;support.apple.com&#x2F;en-us&#x2F;HT210980</a><p>I seems that the new MacBook Air with M1 can&#x27;t play HDR content on external displays. :(

I think I must be some weird outlier on HDR. I recently upgraded to a display that supports it, and when I turn it on, everything just looks darker to me. As though the brightness went to half at the same time that contrast was cranked up high. Playing with color and exposure and other settings just made things worse.

The industry is in a very strange place right now. HDR monitors are both quite expensive and unimpressive compared to the HDR OLED TVs..<p>For the 5-6k that this display from Apple costs, I would certainly expect it to be an OLED display at LEAST. But it&#x27;s not.<p>How is this the best we can get and it&#x27;s NOT OLED? Dimming zones for 6k? I don&#x27;t understand what&#x27;s going on, I just want a nice OLED monitor that will fit on my monitor arm. I&#x27;ll even pay the same price that you can get an AMAZING 55&quot; OLED TV from LG for; 1500-2k.

Mixed HDR&#x2F;SDR content is interesting problem. To me the example where thumbnail is presented with HDR color feels wrong, because it makes the thumbnail to stand out in a distracting way and seems highlighted in some way. But the iPhone example on the other hand looks really good; note how it seems like it switches from SDR to HDR display when the picture is selected. For desktop, maybe the simplest heuristic for choosing HDR&#x2F;SDR is if the the window is fullscreen&#x2F;maximized or not.

Does anyone have a sample photo with brighter-than-white whites that isn’t behind a registration wall?

I had noticed this on my iPhone 11 Pro and I hate it. HDR doesn’t give you “whiter than white”, it just adds more steps of gray.<p>White is white. White on a display is the brightest point the display can display.<p>What Apple is doing, as the article explained, is showing regular white as gray. That’s not cool, that just stupid. It’s exactly what TVs at Best Buy do when showing SD vs HD content: They ruin the regular image just so you can see the difference.<p>The issue is that my monitor is not a demo display, it’s what I use sometimes in daylight, and I’d very much appreciate that extra brightness that Apple takes away from me.<p>You know what this means for you? Everything you see and watch on your computer is not a bright as it could be. On an LCD screen that’s a big deal because suddenly your blacks are brighter (because of the backlight at 100%) and your whites are dimmer (because Apple saves brightness on the off chance that you have HDR content)

I think this same thing happens when displaying HDR photographs. The main photo taken has much brighter highlights, but the rest of the Live Photo frames don’t.

In case anyone is worried about getting free LASIK eye surgery from this at night, the effect seems to dramatically roll off at very low brightness levels.

How might we access this HDR in animated&#x2F;interactive javascript data visualizations?

I have one regret from this article, and that’s the explanation that sRGB hex color #ffffff (255, 255, 255) is being remapped. It’s not. The OS simply isn’t restricting the display pipeline to sRGB anymore, and that allows content which exceeds sRGB to do so.<p>#ffffff is L=100%. What is L=800%? It exists in HDR content, and we can’t just make the web color #ffffff a dim gray to the eye.<p>We must start thinking in terms of HSL or LAB or even RGBL, and consider that L &gt; 100% is where HDR peak brightness lives.<p>HDR’s color space exceeds the luminosity that sRGB hex triplets can represent, and remapping HDR color spaces into sRGB hex gives you horrendous banding and requires complex gamma functions. The CSS colors spec is finalizing on this, but essentially we’re at the last days of hex codes being a great way to express color on the web. They’ll remain good as a last resort, but it’s time to move a step forward.<p>Apple is pinning sRGB hex #ffffff to “paper white” brightness because the hex color specification can’t encompass the full spectrum of monitors anymore. The different between #ffffff and #fefefe can be enormous on a display with 1800 nits of peak brightness, and if you map #ffffff to peak brightness, you burn out people’s eyes with every single web page on today’s legacy sRGB-color Internet (including Hacker News!). That’s why HDR has “paper white” at around 400 lumens in calibration routines.<p>So, then, sRGB hex colors have no way to express “significantly brighter than paper white #ffffff”, and UI elements have little reason to use this extended opportunity space - but HDR content does, and it’s nice to see Apple allowing it through to the display controller.<p>But there’s no way to make use HDR in web content - other than embedded images and videos - if we continue thinking of color in terms of hex codes. This insistence that we remap hex codes into thousands of nits of spectrum is why web colors in Firefox on an HDR display make your eyes hurt (such as the HN topbar): it’s rescaling the web to peak brightness rather than to paperwhite, and the result is physically traumatic to our vision system. Human eyes are designed for splashes of peak brightness, but when every web page is pouring light out of your monitor at full intensity, it causes eye strain and fatigue. Don’t be like Firefox in this regard.<p>“But how do we conceive of color, if not in hex codes?” is a great question, and it’s a complicated question. In essence you select color and brightness independent of each other, and then make sure that it looks good when peak brightness is low, and doesn’t sear your eyes when peak brightness is high.<p>If this interests you, and you’d like to start preparing for a future where colors can be dimmer <i>or</i> brighter than sRGB hex #FFFFFF, here are a couple useful links to get you started:<p><a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=15534622" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=15534622</a><p><a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=22467744" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=22467744</a><p>As a final note, there are thermal reasons why peak brightness can be so much higher than paperwhite: your display can only use so much power for its thermal envelope. Yes, HDR displays have thermal envelopes. So overusing peak white, such as scaling #ffffff to the wrong brightness, can actually cause the total brightness of the display to drop when it hits thermal protections, while simultaneously wasting battery and hurting your users’ eyes.

wow. no one is calling this the hoax it is. it’s reducing contrast on the SDR so that the HDR content is subjectively brighter. i mean it’s fine and all, but you’re not seeing HDR on a non HDR screen. you wouldn’t be able to use it for color grading.

I think that HDR should also be between quotes.

Did Apple really remap white with macOS Catalina on Macbook Pros, and no one noticed? For some reason, I find that hard to believe. But it also makes me believe in the vertical integration powers of Apple: just think about this trickery on Windows!

&gt; The company, long known for shipping high quality, color-accurate displays,<p>This is simply not true; a lie. Everyone in Hollywood and the professional print world who needed color-accurate displays that could be calibrated were using HP Dreamcolor Displays or similar products from companies like BenQ<p>( For example: <a href="https:&#x2F;&#x2F;nofilmschool.com&#x2F;2017&#x2F;12&#x2F;benq-sw271-color-management-monitor" rel="nofollow">https:&#x2F;&#x2F;nofilmschool.com&#x2F;2017&#x2F;12&#x2F;benq-sw271-color-management...</a> )<p>No movie studio does professional color grading on anything else.