Follow Slashdot stories on Twitter

 



Forgot your password?
typodupeerror
×
Graphics Software Hardware

High Dynamic Range (HDR) Technology Analysis 231

THG writes "CoolTechZone.com has published an analysis of Valve's High Dynamic Range, or HDR, technology that enhances graphics in video games. This new video/gaming graphics technology is expected to debut soon with Valve's Half-Life 2: Lost Coast title. According to the article, 'HDR, or High Dynamic Range, is a lighting process that's been designed to emulate in-game or artificially generated lighting to closely mirror the changes we see in the real world. In simpler terms, HDR allows you to make the objects brighter by allowing them to use the full brightness capabilities of the monitor and not just the brightness level at which they have been shot with (or rendered with) in the scene.'"
This discussion has been archived. No new comments can be posted.

High Dynamic Range (HDR) Technology Analysis

Comments Filter:
  • HDR (High Dynamic Range) Technology: An Overview

    Written by Varun Dubey [mailto]
    Manufacturer: Various
    Monday, 31 October 2005


    (Review) - We've all played Half-Life and it's sequel Half-Life 2. The difference between the two games, in terms of graphics, is tremendous, and now Valve has gone ahead and updated the gaming engine to give you a level of detail and realism that you thought wouldn't be possible until perhaps the next round of game releases.

    HDR, or High Dynamic Range, is a lighting process that's been designed
  • by MLopat ( 848735 ) on Tuesday November 01, 2005 @02:32AM (#13921536) Homepage
    Personally, I liked AnandTech's review from a month ago better. If you're interested, its available here [anandtech.com].
    • There was good article on Ars Technica [arstechnica.com] as well, going into a fair amount of technical detail into why Valve's HDR implementation is interesting, and why it took so long (and so many attempts) to create.

      I'm still waiting for the updated Source SDK so I can build maps using HDR - it's something I'm really looking forwards to. Eat your heart out, darkness-obsessed Doom 3 and friends! ;-)
    • From the screenshots, this looks just like the "Post-processing" used by Guild Wars since its release...
    • by default luser ( 529332 ) on Tuesday November 01, 2005 @12:59PM (#13924303) Journal
      You know, it masquraded as a good review, until I read stupid-assed commentary like this:

      Here, we see how the bloom effect starts to put a strain on the lower memory cards. The X800 and, in particular, the 6600 GT are the most memory-limited of these cards, but ATI's X800 does significantly better than the 6600 GT.

      Welcome to Video Rendering 101. Tell me class, which card will be faster, and by how much:

      The 12-pipe, 400 MHz core clock card (x800), or the 8-pipe, 500 MHz core card (6600 GT).

      This isn't hard. The x800, when core-limited, should produce speeds 20% faster than the 6600 GT...and lord almighty, it's a miracle: the x800 is 20% faster than the 6600 GT with full HDR enabled! It must be the EXTRA 128MB RAM, or the 40% FASTER MEMORY SUBSYSTEM. It couldn't be the damn raw pixel processing power advantage.

      And now class, why would the lower-end cards in this test show greater performance loss? Is it because Here, we see how the bloom effect starts to put a strain on the lower memory cards.

      HELL NO.

      It's called CPU-LIMITED. You can't measure true relative performance drops becuase the scene is CPU-limited to approximately 70fps. The 6600 GT is not even able to reach the 70fps mark without HDR, and suffers noticably with it on. The other cards scale as you would expect them to according to raw core clock speed, once you turn up the pixel processing requirements (full HDR), and the 7800 GTX is STILL CPU-limited.

      And then, after mentioning it CLEARLY in the breakdown above that Valve's HDR implementation supports FSAA, AND after seeing plain-as-day that the 7800 GTX is still CPU-limited, the author doesn't try out FSAA performance. A 5-year old could write the same review.

      I wouldn't be surprised at all if most of the language and pictures are verbatim from a Valve-supplied press pack.
  • by irc.goatse.cx troll ( 593289 ) on Tuesday November 01, 2005 @02:32AM (#13921537) Journal
    "This new video/gaming graphics technology is expected to debut soon with Valve's Half-Life 2: Lost Coast title."

    Its okay to post old news, but Lost Coast is already out, as is DoD:S which also uses HDR.
  • HDR Wizards (Score:5, Informative)

    by Anonymous Coward on Tuesday November 01, 2005 @02:33AM (#13921540)
    http://debevec.org/ [debevec.org] lots of info here
  • Wish List (Score:5, Funny)

    by debilo ( 612116 ) on Tuesday November 01, 2005 @02:35AM (#13921547)
    My wish list for Christmas 2005:

    - Ending world hunger
    - Finding a cure for AIDS
    - Making objects brighter by allowing them to use the full brightness capabilities of the monitor

    Only two more to go! Thanks, Slashdot, for bringing this to my attention!
  • "Debut soon"? (Score:5, Informative)

    by micpp ( 818596 ) on Tuesday November 01, 2005 @02:35AM (#13921553) Homepage
    For one thing, Lost Coast is already out, and has been since last week.
    For another, the first Valve game to use HDR is DOD:Source, and that's been out quite a while already.
    And finally, Valve didn't actually invent HDR, so other stuff has already used it.
    • See: That may be true, but HDR is a very broad term, as anandtech said, 'HDR generally speaks to representable contrast in a scene', and:

      At first glance, it is clear that Valve has added the usual blooming features that we would expect from HDR rendering, but there are a couple of new features that Valve has added to keep it interesting.

      Different games such as FarCry have used what they've called HDR, but valve came up with their own list of features which they felt should be present. Several of which hav

      • Different games such as FarCry have used what they've called HDR, but valve came up with their own list of features which they felt should be present. Several of which haven't been seen before.

        The technology was introduced by Valve in DoD Source (as the GP stated), and was fully implemented in at least 2 of the 4 original maps released (Anzio and Avalanche used it to full effect, not sure about the other two).
        The tech demo was released specifically to showcase the lighting technology in the HL2 engine,

    • FiringSquad [firingsquad.com] did a review on it a few months ago.
  • by joeflies ( 529536 ) on Tuesday November 01, 2005 @02:38AM (#13921559)
    Isn't adding more brightness than what the author originally intended somewhat akin to pressing the "Mega-Bass" button on your stereo to get more bass than the musician originally intended? Is that a good thing?

    I think that striving for accuracy and balance of the elements is probably more important than striving for the maximum ____ your system can deliver.

    • by Nirvelli ( 851945 ) on Tuesday November 01, 2005 @02:55AM (#13921627)
      The "Mega-Bass" button doesn't usually give you "more bass than the musician originally intended," it usually just gives you about the same level they intended because the types of stereos with that button generally don't reproduce as much bass as the $1,000/piece reference monitors in the studio that the musicians mastered from.
    • by OblongPlatypus ( 233746 ) on Tuesday November 01, 2005 @02:57AM (#13921634)
      You've missed the point - though I can't blame you, judging by the blurb the article was less than pedagogical when trying to explain HDR.

      This isn't about altering what any "author" intended. On the contrary, HDR is a new tool which lets the "author" do what's intended more easily, assuming what's intended is to achieve realistic lighting in the rendered scenes. Try Anandtech's recent article on the topic, they explain it very well.
    • by yoyhed ( 651244 ) on Tuesday November 01, 2005 @03:00AM (#13921641)
      It's not adding more than the author intended. HDR levels in Source have to be made for HDR; Half-Life 2 and Counter-Strike: Source don't just work with HDR now that Source supports it, the levels still have to be made for it.

      It's a lot more than just a bass boost, since it's not just a brightness increase, but an increase in the range of brightness, allowing for very high contrast. If you go back and look at a Source game without HDR after seeing HDR for awhile, it looks like it has a dark film over it, similar to a digital camera picture looks before being run through auto-contrast in Photoshop.

    • except that the authors are the ones using and implementing hdr. If it was a mod to a game already released I would agree, but the case for most games is going to be to add this as a feature. So I guess to include your example, maybe if Trent Reznor released some track that had mega bass activated through effects that would make sense, but really, im not sure that its the greatest analogy. ;/
    • by rm999 ( 775449 ) on Tuesday November 01, 2005 @03:50AM (#13921764)
      Think of it this way:

      When you wake up at night and you can see the room in nearly pitch black, things appear to be as bright as your room in the morning with the shades closed. Actually, the room in the morning is 1000 times brighter. The "author" of the real world (God?) "intended" the room to be 1000 times brighter by slamming 1000 times more protons onto your retina, but your brain normalizes things to make the world easier to comprehend.

      Now, when you are playing a video game, and you go into a dark room with almost no light, current algorithms don't make it easier to see anything - they present you with a black screen. When you walk out into the sunlight, you get a white screen. This is now the way our brain sees the world, and makes the experience less realistic.

      Audio, on the other hand, can be presented to us nearly perfectly. My headphones can range from 20 Hz to 20 KHz, all the frequencies our ears can hear. The mega-bass thing is therefore useless if you have a decent pair of speakers.

      I guess my point can be summed up with this example: you can make a really good set of speakers as loud as an airplane if you want. Your monitor, however, cannot shine the sun in your eyes.
    • How in the hell did this get modded up?

      Isn't adding more brightness than what the author originally intended..

      As mentioned before, THE AUTHORS ARE THE ONES WHO ADDED THE FEATURE!!!!!! CHRIST!!!11ONEONE

      ..somewhat akin to pressing the "Mega-Bass" button on your stereo..

      NOT EVEN REMOTELY!!!!! I write a bit of electronic music, so I know the general mecahanics of production. The closest analogue I can come up with is running audio through an expander (or a compressor set to a ratio < 1. same thing). What do
    • Yeah, but the brightness on my monitor goes to 11 and I need to compensate for the inferior equipment used by today's artists.
    • Basically, it sounds like they're adding a more realistic lighting to their rendered scenes, and doing a real-time tone-mapping process. I'm currently working on a lab for graphics class on this process :)

      In short, any scene in the real world can have luminance (basically, brightness) values anywhere from .000001 to 10,000,000. You monitor can show values basically from 0 to 255. This has long been a problem in computer graphics, and was a problem in film beforehand. the giant real-life values are HDR. Tone
    • You have an interesting analogy there, but the process behind the "Mega-Bass" button corresponds much more closely to the Gamma-curve adjustment that are popular with players of very dark FPS games - it's a user-controlled decision to boost something they want more of.

      HDR corresponds more closely to a musician deciding to play his guitar through an overdrive pedal rather than 'clean', making the quiet parts louder at the expense of the loud parts maxing out the avaialble range. It's a decision made at the a
  • THANK YOU (Score:4, Interesting)

    by Capt'n Hector ( 650760 ) on Tuesday November 01, 2005 @02:41AM (#13921573)
    Brightness values should have NEVER been bounded above in the first place (and now that I think of it, bounded below, either). The video card should be charged with computing everthing and only then "flattening" the image into something the monitor can display. It could even add some bloom automatically. HDR and motion blur will do wonders for realism...
    • Re:THANK YOU (Score:5, Informative)

      by donscarletti ( 569232 ) on Tuesday November 01, 2005 @03:39AM (#13921734)
      Brightness values should have NEVER been bounded above in the first place

      Ah, I see you have never designed any graphics related software or hardware whatsoever. While it is not possible to make truly unbounded colour brightness levels in graphics, it can be approximated with floating point arithmatic, clever gamma curves or just really big integers (32 bits per channel or so). All of which take a lot of processing power, a lot of memory or both. It has only been a recent thing that graphics card manufacturers have had the powerful technology at their disposal to even think about this, let alone implement these techniques. If we had not had the hack known as 24 bit colour for the last twenty years we would have had nothing.

      Now I come to think about it, the author of that artical doesn't know much better: Radiosity is a way of rendering a scene using only visible light sources WTF? Radiosity is a way of rendering a scene by taking into account light bouncing between surfaces, being absorbed by surfaces and emitted at different wavelengths etc. Pretty much the oposite of what it describes since real radiosity will create an effect similar to ambient lighting. The artical is written by idiots for idiots.

      • Why exactly is it not possible to make truly unbounded color brigthtness levels?
        • Because 3 floats/pixel adds up really quickly. You can do it now, but that was horrendously expensive back in the day. (Heck, 24bpp was considered insanely expensive once upon a time. That's why people used hacks like palettes and indexed images.)

          There's also the question of how you flatten that down to the gamut of the monitor. You're typical monitor has maybe 2 to 3 orders of magnitude. Figuring out the best way to compress HDR down to that scale (i.e. tone-mapping) is still an active area of researc
        • because using an unlimited sized structure for every pixel element would require an obscene graphics card or a tiny monitor, 192x160 anyone?
    • But then a bitmap smoke puff clips through a wall and the game still looks like ass. Seriously, with all that focus on graphics you'd expect that they'd use volumetric effects everywhere by now. Until they do, games will not get any better graphics-wise than Quake 3 did. (Yes, I prefer consistent graphics over eye-candy. If you go out of your way to create an immersive game don't destroy immersion by using nonvolumetric smoke puffs. Or at least make sure that they never ever touch anything else.)
    • And the IDE/ATA address bus should never have been limited to 28-bits in the first place.

      What's your point?

  • why, why did i get a laptop for gaming? my computer can barely render the Sims 2 - yet guild wars runs fantastically... im not getting my hopes up about running Civilization 4... and its only a year and a half old. the sad part is, my card is better than half the laptops cards out there (which have shared memory and wide-screens!).

    i remember years ago, i could still play the games fine if i just turned the graphics down - but that doesnt work anymore! my GeForce 2 lasted more than 2 years, but this one b
    • Don't feel too bad. The XBox 360 is coming out in a couple of weeks and then you'll be able to have a whole seperate system for gaming that plugs nicely into your big screen tv and comes with a dedicated game controller and 3 PPC processors. Best of all it costs about the same as a decent video card.

      OK its not quite as portable as a laptop, but if you want portable get a PSP or DS, they're way cheaper than decent graphics card.
    • Don't feel too bad. I can barely play Doom 3 at 800 x 600 on my desktop. Its about a year old (although refurbished) with a radeon 9600 xt 128mb AIW and a dual xeon 2.0 ghz.

  • HDR and Lost coast (Score:5, Informative)

    by signore pablo ( 544088 ) on Tuesday November 01, 2005 @02:46AM (#13921590)
    After playing Half Life 2: Lost Coast with Full HDR at 1280x1024 and settings all the way at max, I came away with the impression that HDR is really quite nice. Comparing screens with normal filters and HDR, HDR is much more realistic. When you look at water reflections HDR is invaluable. Sun reflections especially looked impressive. Where normal filters made the bright spots look gray, HDR made everything shine and bleed a bit. It was quite accurate as far as the water went. Now, what I didn't think was realistic, was HDR used in the distance. There was that seem bleeding effect across open windows and such. Also, the effect is sampled every so often, I don't know what the sampling rate was there, but a couple times i noticed a slow sampling rate that wasnt entirely realistic. Towards the end of the Lost Coast level, I was impressed by the light coming in from the windows (you'll know what im talking about if you've played it). They were stained glass windows and first there was a dull light in them, but when you shot them out, a big blast of white/yellow light shines through that looks quite good. My conclusion is that HDR is good, but they should up the sampling rate in HL2LC and also change how its viewed in the distance. But what do i know... anyway, thats how i saw it.
  • HDR is a hack (Score:2, Insightful)

    by Doppler00 ( 534739 )
    The truth is, our computer monitors are very limited in the range of colors they can reproduce. We have been stuck with 8 bit RGB for a long time now, I'm surprised we haven't moved on to 16 bit per color or even floating point by now. Internally, video cards in the future will render using floating point arithmatic, but I'm guessing they will still be transmitted as 8 bit per color RGB. Not only that, most image file formats like JPEG are only 24 bit.

    Furthermore, we really need to increase contrast ratios
    • 8 bit colour is pretty much "enough". I realize this may sound like the infamous 640K is enough for anybody, but really, in this case it pretty much is.

      It's more like the situation with CDs -- they're sampled at "only" 44.1khz, and thus unable to capture frequencies higher than half of that. And they have "only" 16 bit resolution. There are newer formats with ridicolous sample-rates and resolutions.

      Witness people yawn. It quite simply doesn't interest the overwhelming majority of the people. What intere

      • Re:HDR is a hack (Score:3, Informative)

        by blincoln ( 592401 )
        It's more like the situation with CDs

        I'd have to disagree with you about that.

        CD-quality audio gets pretty close to the limits of what the average person can hear. It's not perfect, but as you say it meets the "good enough" threshold.

        Current display technology doesn't. Look at this representation of what's lost with sRGB [wikipedia.org]. See what a tiny portion of green colours (which our eyes are most sensitive to!) in particular are represented?

        I went to a concert a few months ago (Dead Can Dance) and their stage lightin
      • 24-bit color can be insufficient when you have synthetic images. Being limited to 8 bits per component can produce banding. 16-bit grayscale and 48-bit color are commonly used for digitized x-rays and medical imaging.
        • I know. But the fact remains: for most of the people, most of the time, higher colourdepth is a negligible or even unnoticeable improvement.

          Sure, for some people, some of the time, it would make sense. Just as there's some people that some of the time need sound-recordings with higher frequency-ranges and/or more sample-accuracy than standard CD.

          I'm just saying there's no significant market for it. In the sense that there's not a large population of people who are willing to pay significantly more to ge

    • Re:HDR is a hack (Score:5, Insightful)

      by famebait ( 450028 ) on Tuesday November 01, 2005 @05:35AM (#13922065)
      HDR is no more a hack than showing natural video on a TV. Sure, the screen has less dynamic range than reality, and you need a mapping function (exposure settings when working with natural light) to display it in a sensible way, but it still pays off hugely to do all the lighting in the scene without regard for that, just as reality dioes.

      The alternative (the traditional 8-bit path) corresponds to a reality where no light can be brighter than the white of the monitor", including when adding up light from several sources! Trying to get real photorealism that way is a lost cause. There's a reason why even holywood CG until recently always looked really 'flat', except in very dark scenes (lower dynamic range to model)

      And for the record: those blooming effects are not part of HDR. They are simply post-process SFX, emulating scattering and other effects in the eye and in cameras. Sure, you couldn't do them really well without HDR, so they're a nice poster child for what it lets you do. But they are not what makes the process HDR.

      Volumetric effects are of course not inherently HDR either; they've eben around a long time, just too heavy to do for most games to bother with until now, and looking much better with HDR (and bloom).
    • try looking up sharp mega contrast, eg

      http://sharp-world.com/corporate/news/051003.html [sharp-world.com]

      uses exactly your suggestion im pretty sure: "backlight" made of an array of leds

      and to all the responses to yourcomment by people with a "24bit colour is good enough" and "cd quality is good enough", what the hell are you doing on slashdot if your not interested in improving technology to the point where its perfect, not just "good enough" (and no, its NOT good enough, many people with keen ears and good eyes, myself

  • by Tidal Flame ( 658452 ) on Tuesday November 01, 2005 @02:52AM (#13921610) Homepage
    The provided definition of HDR isn't very accurate. From Game Developer magazine's August 2005 issue:

    "High Dynamic Range (HDR) rendering is a technique used to retain color precision of a rendered scene as it goes through the rendering pipeline...

    For applications, especially games, this means that our scenes will be rendered in a more realistic manner in terms of lighting. Using high dynamic range rendering we can add a great deal of detail to our applications by retaining as much light information as possible. This will then cause our objects and surfaces to be displayed in a way that comes closer to resembling real life than ever before.

    The problem with non-HDR games is that traditionally, the color precision of a rendered scene is lost, and the rendered display is limite to a low dynamic range of color values between 0 and 255. In the past, this limitation was mainly a result of PC or console hardware only supporting integer buffers, which has a limited range of precision when compared to floating point buffers. Thus, to perform HDR rendering we will need to render our scene to an off-screen floating-point surface, so that the data can be manipulated and made ready to be displayed on the screen."


    Also, it's not Valve's technology. They've implemented it in the Source engine now, but they didn't invent it and I'm pretty sure they're not the first to use it.
    • I wouldn't call it "color precision" so much as I'd call it "rendering the full dynamic range the human eye is capable of seeing in a single scene since 'normal' cameras and imaging/rendering/gaming software does not accurately model the response of the Mark One Eyeball" ... but that's just me.
    • Also, it's not Valve's technology. They've implemented it in the Source engine now, but they didn't invent it and I'm pretty sure they're not the first to use it.
      Far Cry has done this befor in an actual game. And of course there have been tech demos around.
  • Hardware? (Score:2, Insightful)

    by Kasracer ( 865931 )
    Since this is a technology included in software, why is it listed as hardware?
  • Having been previously and currently employed in labratories and RND departments, considering myself to know something about the subject ... id like to point out that this is a TECHNIQUE, not a Technology.
    • by ionpro ( 34327 )
      High Dynamic Range lighting is a technique. Valve's implementation of that technique in the Source engine is a technology.
  • Not Valve's HDR... (Score:5, Insightful)

    by Jerry Talton ( 220872 ) on Tuesday November 01, 2005 @03:00AM (#13921642) Homepage
    I think, if you want to be precise, what Valve did in Lost Coast should be called Paul Debevec's [debevec.org] High Dynamic Range.

    • by Animaether ( 411575 ) on Tuesday November 01, 2005 @08:30AM (#13922461) Journal
      Paul Debevec, through his papers on acquiring low dynamic range imagery and turning that into high dynamic range imagery - and a utility to go with it coded with help from others; HDRshop, has made HDR accessible and popular.

      However, 'HDR' as the storage format being used most frequently already existed in the rendering application Radiance for a long, long time before that.

      In fact, -most- rendering applications render in HDR - but are forced to clip values so that you can actually output it to a regular display (e.g. your TFT) or storage format (e.g. JPG).

      In fact, Valve's HDR isn't an HDR display technology. It's a partial HDR pipeline for rendering (making sure that glints of the sun are bright on water surfaces, and not dull), processing (bloom effects) and simple tone mapping a la a LUT (look into a room from a skylit outside, and the room may appear dark. Walk inside, and the room appears normal whilst the outside world will appear very bright indeed. Note that a more proper tone mapping algorithm would, besides being computationally very expensive, show the room normally and the outside world bright - but not so bright as to be blown out.)

      Once we've all got HDR displays (search on Slashdot for these - I've seen them, they're awesome), we can do away with all these basic gimmicks as the human visual perceptance system will simply do all the interpreting of what should be 'correct' HDR values coming from the display.
  • by Buran ( 150348 ) on Tuesday November 01, 2005 @03:01AM (#13921648)
    High Dynamic Range is also a useful tool in photography, especially for digital photographers who find that the useful dynamic range of a digital camera is less than that of an equivalent film camera. Multiple-exposure bracketing can be combined with the use of special processing software in order to yield images that would be difficult to obtain with a digital camera, or sometimes even a film camera.

    Photoshop CS2 includes this technology out of the box (Photoshop CS2 HDR [luminous-landscape.com]) -- in the demo page, notice that the sky is properly exposed as well as the vegetation on the hill in the foreground; this would be impossible to capture with many cameras. As the article linked by the original post states,

    "HDR, or High Dynamic Range, is ... designed to emulate ... lighting to closely mirror the changes we see in the real world."

    And indeed that's what the photographic equivalent does. Unlike a camera, our eyes can properly "expose" the ground as well as they can the sky in the same scene. In fact, this is mentioned on pages 2 and 3 of the linked article in the original post.

    More:

    HDR - High Dynamic Range Compression - a Photoshop plugin [powerretouche.com]

    The Future of Digital Imaging - High Dynamic Range Photography (HDR) [cybergrain.com]

    Aizu University's Atrium High Dynamic Range Source Images [mpi-inf.mpg.de]

    High dynamic range imaging - Wikipedia, the free encyclopedia [wikipedia.org]

    Stitched HDRI [gregdowning.com]

    If you would like to try this yourself, many digital cameras have a bracketing feature. I'd suggest at least five exposures, separated by one half stop or one full stop. However, it does not work well for moving objects since there will be a short amount of time that elapses between exposures.

    Here is my first attempt:

    High Dynamic Range Candy Corn [buran.org]

    This particular shot was taken with a Canon EOS 1Ds MkII camera and manual bracketing, although I've made other successfull attempts with the bracketing feature of my Nikon D70.
    • notice that the sky is properly exposed as well as the vegetation on the hill in the foreground; this would be impossible to capture with many cameras.

      Graduated neutral density filter. Cokin makes a nice kit.

      Actually a whole lot of what gets done in photoshop can be done much faster at exposure time. Like lighting colour adjustments (warming/cooling filters), Increasing colour saturation (polarizers), selective focus (large aperature and/or vaseline smeared UV filter), perspective correction (proper came

  • by rm999 ( 775449 )
    Lost Coast is already out. And yes, HDR looks great - it was probably the most impressive part of Lost Coast. I hope that we see it in all future 3d games.
  • Auto-auto-levels (Score:2, Insightful)

    by kappa ( 104316 )
    Looks like they apply auto-levels to each frame. That shouldn't affect performance a lot, btw. It is really a work-around for bad rendering. They could fix low dynamic range earlier in the output pipeline.
  • by Max Romantschuk ( 132276 ) <max@romantschuk.fi> on Tuesday November 01, 2005 @04:00AM (#13921788) Homepage
    A chain is only as strong as it's weakest link.

    Too bad the BrightSide [brightsidetech.com] display is "a little costly"... (Think several small cars -costly.)
    • True HDR would require screens that were as bright as the sun, sure, but then we'd all go blind watching sunsets on TV. The effect desired is to make the mind see what it would see in those situations where there is very bright and very dark areas in the same space.

      If you're on a bright beach, it looks bright, but not nearly as bright as when you first look out your hotel room at it. A good HDR implementation would make the beach brighter when you first look at it, for example.

      Burnout 3 Takedown on the PS
  • HDR in action (Score:4, Interesting)

    by roxtar ( 795844 ) on Tuesday November 01, 2005 @04:14AM (#13921833) Homepage Journal
    One of my friends has a Geforce 7800 GTX. Here [flickr.com] are [flickr.com] some [flickr.com] screenshots [flickr.com] of Farcry with HDR enabled.
  • by FromWithin ( 627720 ) <mike AT fromwithin DOT com> on Tuesday November 01, 2005 @04:15AM (#13921837) Homepage
    The major part of HDR (excluding glare and all that), is that it is a way to model the way that the iris (the black bit in the middle of your eye) opens and closes at different brightness levels.

    There is something missing though, which I think would be beneficial. Basically, the eye has rods and cones for luminance and colour respectively. The rods are far more sensitive than the cones, with the result being that in very low light conditions, we see in greyscale. I have never seen this effect in a game (or film), and I think it would really enhance the realism, especially in darker games like Doom3. It would be even better if the display could become slightly blurry and noisy as the rods are not as high resolution as the cones.
  • new technology? (Score:2, Informative)

    by two.oh ( 721094 )
    HDRI has been around for a long time --since the late '90's. I don't understand why this is considered new, especially since Paul Debevec introduced this at Siggraph in '99 (?) in Fiat Lux. It's been in almost all the latest big VFX movies to date. HDRI is not a "a lighting process that's been designed to emulate in-game or artificially generated lighting". It is a method of lighting scenes using real-world lighting scenarios. I suppose this is new to the video game industry, but this has been around f
  • by vectorian798 ( 792613 ) on Tuesday November 01, 2005 @04:20AM (#13921857)
    HDR has been around for a longer while than you think. It has been used in games before, it has been demoed before. Some of you may recognize HDR in the form of light blooms, especially from the earlier screenshots of the Unreal 3 Engine, as seen here:
    HDR Glow in Unreal 3 [unrealtechnology.com]

    Although some say light blooms are NOT high-dynamic range (which is true for the case where you just make something radiate light in a way that washes out details of objects around it - see here [wikipedia.org]), light blooms can be done with high-dynamic range color, which is what the Unreal 3 Engine [unrealtechnology.com] page mentions in a brief caption for the above picture.

    Anyways, there are other games that ALREADY do HDR, such as Far Cry (with patch 1.3 or above). The best place to get a good view of it is ON a beach in Far Cry that is directly in the sun. It is funny that Far Cry has been ignored as the first of its kind in many things, but it really did do a lot of stuff that Doom 3, Half Life 2, etc. did, except earlier. It was also virutally bugless, compared to for example, the stuttering bug common in Half Life 2. Most are misinformed in crediting games such as HL2 or D3 in bringing in the generation of shader-heavy games (aka 'next gen' games).

    That being said, if you don't know what HDR is, the Anandtech Article [anandtech.com] on HL2:TLC is a good read.
  • Finally! I've been waiting for the day developers would decide my graphics card with its high-res 32-bit textures displayed on 1600 by 1200 with maximum draw distance, 3 kinds of filtering, and 8 layers of model mesh effects would look better washed out anytime the sun is up.

    I can see it now- Unreal Tournament 2007: Pre-Order and get a FREE pair of Eagle-Eye sunglasses using patented NASA anti-glare technology!

    Just give me the damn Kryptonite fog already. Serves us right for letting game designers use that
  • Either HDR is a bunch of crap or the explanation is. I'm reminded of Nigel of Spinal Tap explaining how his amp is better because it goes to eleven.
  • I hate to be "one of those people" but this article sucks - four really short pages and not a single screenshot - WTF?!? If you want to *see* Valve's HDR, you'll do no better than bit-tech's series of articles:
    Half Life 2: Lost Coast HDR overview [bit-tech.net]
    Half-Life 2: Lost Coast review [bit-tech.net]
    Half-Life 2: Lost Coast Benchmarks [bit-tech.net]
    Day of Defeat: Source review [bit-tech.net]
  • HDR, Half Life 2: Lost Coast, and the Future of Gaming [brentonwalker.com] -- Has a lot of good examples of what HDR exactly involves.
  • Another article about HDR that doesnt actually explain what is really is. It starts off ok but then falls appart. Bloom isnt HRD, Exposure control isnt HDR, Radiosity isnt HDR...whats more all of things are possible in LDR (though exposure control is a bit difficult). HDR just makes everything more realistic. The stuff about the contrast ratio of displays. The final contrast ratio of the image isnt what HDR is about either. The it will be important with newer monitors. I mean a LDR image has a contrast
  • by Emil Brink ( 69213 ) on Tuesday November 01, 2005 @07:04AM (#13922285) Homepage
    As very many have already pointed out, that was indeed a crap article. I don't want to spend any time quoting it and going "WTF?!", but I *do* want to link to OpenEXR [openexr.com], which is a file format for managing HDR images. It typically uses 16-bit floating point numbers per pixel, which seems to give a decent brightness range. It's cool to watch the same image rendered using different levels of "virtual exposure". It's by Industrial Light and Magic [ilm.com], which some of you might have heard of. I have, of course, no affiliation with either, just wanted to link to something relevant.
  • Bit-tech.net has an Article [bit-tech.net] on Half Life-Lost Cost which has screenshots showing effect of HDR and link to a video.
  • Turning up the contrast and brightness on a sprite does not strike me as revolutionary. Is there something special about how they're doing it?
  • Anyone here familiar with Gradient Domain High Dynamic Range Compression [huji.ac.il]? Truly stunning imagery, but I've been having a bitch of a time actually trying to code the given algorithm. I don't suppose someone else already has? The examples look truly, truly fantastic.
  • by ameline ( 771895 ) <ian.ameline@Nospam.gmail.com> on Tuesday November 01, 2005 @10:21AM (#13923025) Homepage Journal
    for more bits per color channel. 8 bits is clearly not enough. 12 bits (linear) is almost, but not quite enough to represent what film can, or what the human eye can see. 16 bits is enough. But not for everything...

    A seond use for more bits is various image based rendering techniques. For these, 16 bits is often not enough, unless you go floating point -- and even then, 32 bit floats will produce better results. These techniques often use "blacker than black" (negative values) and "whiter than white" (values > 1.0) as intermediate results of calculations.

    As a side note lamenting the demise/withering into obscurity of a once great company, starting around 1992 with the reality engine, SGI made graphics pipelines with 12 bit/channel RGBA support from end to end. It is only recently that we see support for more than 8 bits/channel in the pc world.

  • by miyako ( 632510 ) <miyako AT gmail DOT com> on Tuesday November 01, 2005 @12:21PM (#13923973) Homepage Journal
    I think that technologies like this being refined are really where the future of gaming graphics is going to be for a while. While there is still a ways to go in terms of polygon count, texture and bump mapping, etc, a lot of progress has been made in these areas. I think what we will see (or hope to see anyway) offered in newer games is more support for technologies that simulate real time lighting, shadows, translucance, refraction, etc. A large part of this I think is that there are only so many resources that can be dedicated to artists now to create higher polygon count models and higher resolution more diverse textures, so things that can be done to increase the visuals of a game without having to dedicate significantly more resources to artists can vastly improve the visual quality of a game without such a significant increase in cost associated with actually crafting those visuals. With technologies such as this allowing a more realistic rendering of ourdoor scenes combined with improving algorithms for creating outdoor environments and the ability to create fractal plantlife I think that we will see a new generation of games that take the player more and more often into the less confined feeling outdoor world.

A morsel of genuine history is a thing so rare as to be always valuable. -- Thomas Jefferson

Working...