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HDR Video a Reality

akaru writes "Using common DSLR cameras, some creative individuals have created an example of true HDR video. Instead of pseudo-HDR, they actually used multiple cameras and a beam splitter to record simultaneous video streams, and composited them together in post. Looks very intriguing."

59 of 287 comments (clear)

  1. The holy grail of camera tech.... by Above · · Score: 3, Interesting

    HDR

    Focus Stacking

    Panoramic Stitching

    All in the camera, all 1-button easy to use, and all at once.

    1. Re:The holy grail of camera tech.... by fractoid · · Score: 4, Funny

      wtf? no intelligent aperture, unlimited storage and battery life? wake me up when obama sends me one for free.

      You have two of those embedded in your friggin head. :P

      --
      Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
    2. Re:The holy grail of camera tech.... by Lehk228 · · Score: 5, Funny

      and it also has to give BJs

      --
      Snowden and Manning are heroes.
    3. Re:The holy grail of camera tech.... by Prune · · Score: 4, Interesting

      You forgot about full lightfield capture. This can be done with a single camera using ultra high resolution and a microlens array (or alternatively, an array of a very large number of tiny cameras). Think single camera, single shot capture of depth (3D) and all focus planes. Then you can reproduce the full 3D and multiple focus depths (as in, the eye would have to focus at different depths) on a flat display with microlens array covering it (again, need ultra-high resolution since focal depths and parallax viewpoints are discretized to the pixel number covered by each micro lens).

      --
      "Politicians and diapers must be changed often, and for the same reason."
    4. Re:The holy grail of camera tech.... by Prune · · Score: 3, Interesting

      You don't need aperture at all if you use a microlens array to do integral photography. On top, you get full depth (3D) and capture all focal lengths, including the focal depth information. All in a single shot. Just need an ultra high resolution sensor--or, instead, an array of many small cameras (works just as well, and no need for perfect alignment as that can be finessed in software). You capture a full 4D lightfield (light can be parameterized as the two pairs of coordinates of a light ray crossing two infinite planes), i.e. miss no optical information whatsoever other than your diffraction and wavelength limits.

      --
      "Politicians and diapers must be changed often, and for the same reason."
    5. Re:The holy grail of camera tech.... by aliquis · · Score: 5, Funny

      and it also has to give BJs

      Just get a cheap camera phone, those cameras all suck.

    6. Re:The holy grail of camera tech.... by Sulphur · · Score: 2, Funny

      Cash for clickers.

      --

      Do you have a digital camera? No I have an analog camera.

    7. Re:The holy grail of camera tech.... by HizookRobotics · · Score: 2, Informative

      This goes a long way toward the "computational camera" where you get flexible depth of field (focus at many depths), trading off pixel resolution for HDR / multispectral imaging, and other cool techniques (like stereo). Exciting stuff!

    8. Re:The holy grail of camera tech.... by grcumb · · Score: 2, Interesting

      and it also has to give BJs

      ... Actually, forget the HDR, focus stacking, panoramic stitching and the rest. I say we put all the R&D money into BJs!

      --
      Crumb's Corollary: Never bring a knife to a bun fight.
    9. Re:The holy grail of camera tech.... by JambisJubilee · · Score: 2, Funny

      Yeah right, like I'm going to wait for Obama to send it through the US post. YAWN. Wake me up when he's using FedEx Priority. At least I can get delivery confirmation on my Backberry.

      Until the cameras have intelligent aperture, unlimited storage and battery life, AND use FedEx Priority, I'm not interested

    10. Re:The holy grail of camera tech.... by Anomalyst · · Score: 2, Funny

      All images must be pre-approved by Apple before storage.

      --
      There is no right to feel safe thru security vaudeville at the expense of everyone's freedom, privacy and tax money.
  2. The trumping technology to follow: by DWMorse · · Score: 3, Funny

    The trumping technology to follow: 3D-HDR Video!!

    --
    There's a spot in User Info for World of Warcraft account names? Really?
    1. Re:The trumping technology to follow: by c6gunner · · Score: 3, Funny

      "It's a motion picture in technicolor. With sound!"

  3. a text C&P from the article by kaptink · · Score: 4, Informative

    C&P from the linked page (assuming a /.'ing imminent)

    HDR demo @ http://vimeo.com/14821961

    Press Release:

    HDR Video A Reality

    Soviet Montage Productions releases information on the first true High Dynamic Range (HDR) video using DSLRs

    San Francisco, CA, September 9, 2010: Soviet Montage Productions demonstrated today the first true HDR video sourced from multiple exposures. Unlike HDR timelapse videos that only capture a few frames per minute, true HDR video can capture 24 or more frames per second of multiple exposure footage. Using common DSLRs, the team was able to composite multiple HD video streams into a single video with an exposure gamut much greater than any on the market today. They are currently using this technology to produce an upcoming film.

    Benefits of Motion HDR
    HDR imaging is an effect achieved by taking multiple disparate exposures of a subject and combining them to create images of a higher exposure range. It is an increasingly popular technique for still photography, so much so that it has recently been deployed as a native application on Apple’s iPhone. Until now, however, the technique was too intensive and complex for motion. Soviet Montage Productions believes they have solved the issue with a method that produces stunning–and affordable–true HDR for film and video.

    The merits of true HDR video are various. The most obvious benefit is having an exposure variation in a scene that more closely matches the human eye–think of filming your friend with a sunset at his or her back, your friend’s face being as perfectly captured as the landscape behind them. HDR video also has the advantage of reduced lighting needs. Finally, the creative control of multiple exposures, including multiple focus points and color control, is unparalleled with true HDR video.

    “I believe HDR will give filmmakers greater flexibility not only in the effects they can create but also in the environments they can shoot in” said Alaric Cole, one of the members of the production team, “undoubtedly, it will become a commonplace technique in the near future. ”

    Contact:
    Michael Safai
    Soviet Montage
    201 Spear Street #1100
    San Francisco, CA 94105
    1 415 489 0437
    mike@sovietmontage.com

    --
    Those who can, do. Those who cannot, sue.
    1. Re:a text C&P from the article by lgw · · Score: 5, Funny

      TL;DR: in Soviet Montage, camera manages multiple exposure for you.

      --
      Socialism: a lie told by totalitarians and believed by fools.
    2. Re:a text C&P from the article by thrawn_aj · · Score: 2, Interesting

      So, HDR video would help make movies look like ... video games??? Is it just me or does that video (that parent linked to) look amazingly like a (post-HalfLife2) game? I guess this should be a fantastic clue for game programmers who usually try to go the other way ;). Lack of HDR = more "realistic" video? (where realistic is defined by what people are used to). Find an algorithm to intelligently degrade the dynamic range in a rendering and CGI becomes more photorealistic.

    3. Re:a text C&P from the article by yoyhed · · Score: 4, Interesting

      It's the other way around.

      Even though we call it high dynamic range in videos and photographs, it's actually just compressing all the extra information from multiple exposures into a LOWER dynamic range, so we can manipulate/display it on our 8-bit screens.

      Games, however - such as the Source engine after it got the HDR update with Half-Life 2: Lost Coast and Day of Defeat: Source, actually do increase the dynamic range of a scene beyond what your monitor can display. They underexpose and overexpose parts of the scene when transitions between light and dark places occur, just as your eyes would before they adjusted to the new light, or as a video camera would depending on what exposure the videographer chose. This makes it look more realistic - just take a look at a bright outdoor scene in Half-Life 2: Episode Two and check out how shiny objects in the sunlight have blown-out highlights that gleam brilliantly, and then look at the same scene in the original Half-Life 2, where that object would look flatly-lit and fake. The "non-HDR" looks more fake because the dynamic range is compressed so you can see all the detail everywhere, which also gives it that flat "game" look.

      Of course, that last part is just my opinion - but I believe that in order to look more realistic, CGI needs to simulate the behavior of traditional cameras with a lower dynamic range (or that of your eyes before they've adjusted properly to bright/dim light). The everything-is-exposed-properly, compressed-dynamic-range look just appears fake to me, even though my eyes could probably perceive that range at the actual scene. I'm not sure why.

      --
      WHO NEEDS SHIFT WHEN YOU HAVE CAPSLOCK/ DAMN1
  4. HDR? by afaik_ianal · · Score: 4, Interesting

    Can anyone give a brief rundown on what HDR is? I know it stands for "high dynamic range", but as someone who knows nothing about photography, it means nothing to me. What it has to do with overexposure/underexposure (to which the video refers)? Why is it harder to do with video than still images?

    1. Re:HDR? by mtmra70 · · Score: 5, Informative

      Wiki explains it well:
       
       

      is a set of techniques that allow a greater dynamic range of luminances between the lightest and darkest areas of an image than standard digital imaging techniques or photographic methods.

      And their picture is a great example. If you expose the building well, the clouds are washed out. If you expose the clouds well, the building is dark. If you take pictures of both equally exposed then merge the photos, you now have a properly exposed building along with a properly exposed sky giving thus giving you more dynamic range. Think of it like instead of going to the lunch buffet and cramming everything into one plate, you go up to the buffet three times with three plates: one for salad, one for main course and one for dessert. With a little processing (trips) you end up with more range (food variety).

    2. Re:HDR? by treeves · · Score: 3, Informative

      It requires post-processing. You combine images shot at bracketed (above and below the "optimum") exposures, in order to get the details in both the brightest and darkest parts of the image which are sometimes lost in high contrast situations. You end up compressing (to use an audio analogy) the brightness range into a smaller range so it can be reproduced on a monitor or paper.
      The post-processing of a LOT of frames requires a lot of processing power and time.

      --
      ...the future crusty old bastards are already drinking the Kool-Aid.
    3. Re:HDR? by lee1026 · · Score: 2, Insightful

      Well, a camera can only capture so much of the difference between the brightest parts of the image and the dimmest part of the image. How HDR works is that you take one picture that is extremely dark, and then you take another picture that is extremely bright, and you merge them together so that the resulting picture can capture more of the super bright parts and more of the super dim parts. Now, the problem for video is that it is hard to take the bright shots and the dim shots at the same time, because you need for the cameras to remain where they are.

      These guys solved that problem by using a beam splitter to redirect the same light to two cameras.

    4. Re:HDR? by EnsilZah · · Score: 2, Interesting

      I'm no expert on the subject but the basics as I understand them are you take several photos at different exposures, that way you have all the details in the dark areas from the overexposed photo, the details in the bright areas from the underexposed photo (that would otherwise be burnt out) and you can even use an HDR image for lighting a 3D scene by I guess analyzing the nonlinear way lighting changes between exposures (this area I'm a bit less clear about)

      It's difficult to do for video since for a still image you just take different photos without moving the camera, so you need to share the same point of view but it can be at different times given a static scene, with video you need to share both the point of view and the time so it requires, as they did here, splitting the same image into two and having two cameras record at two different exposures.

      What I'm not sure about is why you can't just use a single exposure and make copies of the current states along its duration, probably has something to do with sensor response times and or the method used to read from it being destructive.

    5. Re:HDR? by BitHive · · Score: 3, Funny

      Now you tell me! I've been trying to click enter for the last hour and it's been incredibly frustrating.

    6. Re:HDR? by jack2000 · · Score: 2, Insightful

      HDR looks so unreal even if at times aesthetically pleasing. Their "more real" filter didn't do the scene much justice too.
      Was the guy supposed to look that way?

    7. Re:HDR? by mtmra70 · · Score: 4, Informative

      HDR looks so unreal even if at times aesthetically pleasing. Their "more real" filter didn't do the scene much justice too.
      Was the guy supposed to look that way?

      The video was not very good at all, so I'm not sure why it is a big deal. The video of the guy was more HDR than any other part, though it was very strange.

      Take a look at some of the HDR photos on Flickr http://www.flickr.com/groups/hdr/pool/. They give much better and proper example of HDR.

    8. Re:HDR? by ADRA · · Score: 2, Informative

      I'm not an expert, but from my limited knowledge:

      HDR is taking frames of varying exposure levels and merging them into a single picture that contains color levels combined from both. It would help in correcting contrast washout areas of the image that aren't the target exposure of the image without needing touch ups. Taking HDR pictures at multiple exposure levels allows for a richer range of captured detail. When I overexpose in sunlight, I get an effect that takes all detail away from a darker piece of the scene. This may be intentional if I'm looking to over saturate other areas of the image using optical capture techniques. Having the same effect could be simulated in post processing by adjusting levels of specific parts of the image, but that's more time consuming and may not lead to the best results. Having one image under exposed and another overexposed means that the richness of each color range can be captured as they were when shooting. That gives a director a lot of power in changing the composition of a shot without needing to re-shoot or do more laborious processing techniques.

      It is hard to do period, because any optical capture device has a set exposure that they are capturing for. The other issue is that the image has to be identical basically identical. Any variation (such as time delay between image captures) can cause ugly or unwanted side-effects that would require cleanup later on. Applying this principle to video capture, you -could- have a camera and single lens/sensor taking images at twice higher speeds, but that means reducing the possible exposure times by at least half which ultimately limits the possible lighting conditions that one could shoot HDR in (hard/impossible in the dark?). One could shoot two cameras simultaneously, but then again the problem is that because the images aren't exactly perfect which would lead to ugly artifacts. For close ups, this is all but infeasible because these artifacts become larger and more apparent. Think of this as the anti-3D concept. You want two pictures being taken at the same time, but instead of having them offset based on the capture view plane, the photographer wants them as close to identical in terms of angle / offset as possible. For 3D-HDR movies, you'd need at least 4 simultaneous frames being captured at all times (two left, two right)

      These guys' solution seems to be taking one lens and by applying an beam splitter (http://en.wikipedia.org/wiki/Beam_splitter) (which ultimately reduces the amount of incoming light) cuts the frame identically between two channels which gets fed into two Canon cameras (capturing video) who are set to varying exposure timings. They've chosen to use 2 stops+/- and I don't really know if that's the ideal for HDR capture or if its just the maximum automatic exposure variation they can choose in the 'pseudo-auto' exposure modes built into the cameras.

      --
      Bye!
    9. Re:HDR? by ColdWetDog · · Score: 4, Informative

      That's one of the problems with HDR photography. The light to dark transitions just don't look quite right and so the scene has an 'unreal' appearance. Either washed out or cartoonish.

      You see that all of the time in still HDR photography and I think it has to do with the limitations of the final media - movie screens, paper, computer screens - that do not reproduce the eye's ability to deal with contrast well. In prints, you can work with this and minimize but not completely remove the effect. I imagine that they could tweak their algorithms a little better but Internet video isn't a particularly high quality visual experience in the first place so there well be some limitations in how well they can do it.

      --
      Faster! Faster! Faster would be better!
    10. Re:HDR? by plover · · Score: 4, Interesting

      One problem I realized after watching the scene with the guy is the video compression artifacts can be different between the two cameras. Even if the sensors were perfectly aligned with each other and the optics, the MPEG compression could be different because the values at each pixel will still be slightly different due to the differences in exposure levels. Different pixel values can cause different compression schemes to be invoked in each block, which will result in weird combinations of aliasing. I think this may have been partly responsible for the shimmer on his denim jacket.

      --
      John
    11. Re:HDR? by petermgreen · · Score: 2, Insightful

      and I think it has to do with the limitations of the final media
      indeed, a normal monitor has a limited dynamic range. With many modern LCDs each channel is only 6 bit!

      So if you want to make both the shadow and highlight detail in a a high dynamic range image visible on a normal monitor you will have to compress the dynamic range down.

      --
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    12. Re:HDR? by im_thatoneguy · · Score: 4, Insightful

      "HDR" images don't look unreal. Tonemapped HDR images look unreal.

      You can do the same thing to Low Dynamic Range Images, and they'll look just as unreal. Similarly you can take a 18 stop HDR image and apply normal image processing techniques and get realistic looking images.

      The *only* defining aspect of HDR images is the large amount of dynamic range they contain. The fact that people abuse that dynamic range is an aesthetic one completely separate of HDR.

      It's like saying that Photoshop makes images look fake. *Photoshop* doesn't make images look fake, bad artists make images look fake. You don't have to apply a stock lens flare to your family photo. It won't be too long before all cameras just shoot HDR. The largest application then will be to adjust the exposure at home without worrying about under or over exposing that shot of your friends on the beach.

    13. Re:HDR? by icegreentea · · Score: 5, Informative

      You can get HDR to look 'fine' or whatever adjective you want to use. It's just hard. The tone-mapping software/settings that many people use will just go and create doll skin and haloes everywhere. But if you do everything well (hard work!) you can get some really cool looking stuff. For example...

      http://www.flickr.com/photos/swakt1/2322363690/
      http://www.flickr.com/photos/swakt1/2322366898/in/photostream/
      http://www.flickr.com/photos/ten851/4972637653/in/pool-hdr

      Somewhat like many other art techniques, when best used, you barely notice it at all. And that is the most important thing to remember. HDR + tone mapping isn't just a technology, it is an art. Being able to capture video in 3 different stops at once is great, but it'll still look like crap unless you treat it with respect and give it the effort and time needed.

      Remember, HDR + tone mapping is just trying to create a low dynamic range image on a low dynamic range display that LOOKS something like what your mind perceives in a high dynamic range environment. Obviously, that's kinda hard, especially since the human eye can change its sensitivity as it focuses on different parts of a scene in real life, but not really when looking at a computer screen or print.

    14. Re:HDR? by Prune · · Score: 2, Insightful

      They record HDR but then they compress the image to LDR (low dynamic range) for display on a regular monitor. You don't see the HDR display, just the result of the tone-mapping algorithm that transforms the HDR data into an LDR one. This is a common abuse of the term HDR. It's the same thing with the graphics effect in games. The internal processing is HDR, but then it's tone-mapped to LDR for display on a regular monitor, often with the addition of simulated bloom on overexposed areas. It's unfortunate that so many people see bloom and think HDR, but then again marketing is a common factor in many forms of misinformation.

      --
      "Politicians and diapers must be changed often, and for the same reason."
    15. Re:HDR? by Prune · · Score: 2, Informative

      HDR would look real if displayed as HDR--on an HDR display (Brightside Technologies had demoes of hardware at several SIGGRAPH instances). Instead, they display the output of a tone-mapping algorithm that transforms the HDR to LDR for display on a normal monitor that only has a low dynamic range. The only thing they're doing different is that they're using an algorithm to reduce the dynamic range, instead of the camera's sensor, because the sensor does it in a 'dumb' way--by being over- or underexposed, whereas a tone-mapping algorithm can preserve detail by nonlinearly and usually location-adaptively compressing the dynamic range.

      --
      "Politicians and diapers must be changed often, and for the same reason."
    16. Re:HDR? by nomel · · Score: 2, Informative

      There's some motivation to get the "pixels" to respond like the human eye, or the retinal response model, giving the most realism...although, this probably would be tweaked to give some effect since super real isn't necessarily the goal *cough* 24pfs video *cough*.

      Here's a cool paper:
      http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.109.2728&rep=rep1&type=pdf

      They must not have access to the "raw" data stream for video, because these sensors have a pretty huge dynamic range, around +/- 2 stops. This is the reason pro's shoot in the "raw" format. It saves the pixel brightness data, each pixel in the Bayer pattern, as 14bit values, so you can adjust the exposure afterwords. This is what makes single image HDR possible. I imagine that the camera manufacturers will eventually do something like shown in that paper. Or, maybe they'll get the Super CCD (by Fujifilm) style sensor to work better.

    17. Re:HDR? by nomel · · Score: 2, Insightful

      Well of course not. It's a compression into a small dynamic range that our 8 bit per color channel (hahahahah!) monitors provide.

      And, unless we go back to per pixel light generation and get rid of this backlight nonsense (full power for a black image!?), I'm not sure I want a screen bright enough to provide decent HDR!

    18. Re:HDR? by davolfman · · Score: 4, Informative

      They used more of a dragan-ish style of HDR here. They set it up to preserve local contrast at the expense of actually mapping brightnesses linearly. That's why it looks so freakish: some tones are brighter than other tones that should have a physically higher brightness.

    19. Re:HDR? by Fri13 · · Score: 2, Interesting

      But they still do have the syncing problem when using a D-SLR's. Even that 5DMKII can shoot HD video, it can not be used for real 3D work neither. The cameras do not have perfect sync for frames. The framerate is choppy. Very short videos can be taken but longer ones bring lots of problem in the postprocess. As the framerate can change while recording from 29,97 to 29,98 and so on. That is not so bad thing for HDR but it still exist, and for 3D that would cause lots of problems as both eyes notices the out-of-sync problem and it just is terrible to watch.

    20. Re:HDR? by sexconker · · Score: 2, Insightful

      They record HDR but then they compress the image to LDR (low dynamic range) for display on a regular monitor. You don't see the HDR display, just the result of the tone-mapping algorithm that transforms the HDR data into an LDR one. This is a common abuse of the term HDR. It's the same thing with the graphics effect in games. The internal processing is HDR, but then it's tone-mapped to LDR for display on a regular monitor, often with the addition of simulated bloom on overexposed areas. It's unfortunate that so many people see bloom and think HDR, but then again marketing is a common factor in many forms of misinformation.

      No, you fucking moron, you are simply 100% WRONG.

      For this video, they are recording in LOW RANGE (YUY2 or YV12), and then combining the stills of two different video streams in order to futz the two LOW RANGE videos taken at different SPACES in the sensor's RANGE into a single LOW RANGE video that preserves the RANGE of each separate image DYNAMICALLY in certain AREAS of the final, LOW RANGE, video.

      For HDR photos, the only difference is that they're shooting in their camera's RAW format (or they should be) so they have more control over how each individual photo is level-mapped to the final output photo.

      HDR is DESIGNED for LOW RANGE DISPLAYS.
      There is no such thing as a HIGH DYNAMIC RANGE display. This would be a display that artificially adjusts contrast levels in specific areas of the display while still living in the fixed contrast level of the overall display.

      HDR images on an "HDR display" would be DOUBLY molested.

      An HDR image on a high range display would look just like an HDR image on a low range display. You could stretch the contrast of the image artificially via some filter built into the display, but this is no different than stretching 4:3 content to fill a 16:9 display.

      When you're talking about HDR photos being compressed to LDR, what you're referring to is the mapping of RAW, 12-bit, 16-bit, etc. images to an 8-bit space. This process has NOTHING TO DO with HDR, regardless of whether or not you've applied HDR to a set of RAW images.

      Again, there is no such thing as a LOW DYNAMIC RANGE display. There is no such thing as a DYNAMIC RANGE display. All displays are fixed range, and all image formats are fixed range.

      The "dynamic" in HIGH DYNAMIC RANGE means that the contrast WITHIN dark/light areas is preserved, but the overall original-to-output brightness mapping is DYNAMIC; the mapping is different for different areas of the output image.

      In the following examples, the widths of things represent the contrast / color range.


      This is a normal photo:

      [___SCENE____CONTRAST____RANGE___]
      ----exposure----[SENSOR_RANGE]----

      Take picture, with a set exposure offset, record sensor data.

      [SENSOR_DATA]

      Map sensor data to image format of choice for final display.

      JPEG: [SENSOR_DATA] --> [JPEG]
      Something better than JPEG: [SENSOR_DATA] --> [BETTER_FORMAT]
      RAW: [SENSOR_DATA] --> [SENSOR_DATA]

      This is an HDR photo:

      [___SCENE____CONTRAST____RANGE___]
      ------exposure------[SENSOR_RANGE]
      ---------[SENSOR_RANGE]--exposure-
      [SENSOR_RANGE]------exposure------

      Take multiple pictures at different exposure settings, record sensor data.

      [SENSOR_DATA]1
      [SENSOR_DATA]2
      [SENSOR_DATA]3

      Combine [SENSOR_DATA]s into a single image by defining different areas and combining them:

      Area 1: Use [SENSOR_DATA]1 and futz edges with [SENSOR_DATA]2

      Area 2: Use [SENSOR_DATA]3 and futz edges with [SENSOR_DATA]1

      Area 3: Use [SENSOR_DATA]2 and futz edges with [SENSOR_DATA]3

      Area 1 + Area 2 + Area 3 = [IMAGE__DATA]

      Note the widths of [SENSOR_DATA] and [IMAGE__DATA].

      Map image data to image format of choice for final display.

      JPEG: [IMAGE__DATA] --> [JPEG]
      Something better than JPEG: [IMAGE__DATA] --> [BETTER_FORMAT]
      RAW: [IMAGE__DATA] --> [IMAGE__DATA]

    21. Re:HDR? by sexconker · · Score: 2, Insightful

      You're an idiot.
      Not only is that display not using the same principles as HDR photos, it's not calculating the contrast ratio in any way that makes sense.

      HDR is any image, video, display, or camera sensor that contains more than 8 significant bits per pixel per channel.

      YOU HAVE NO IDEA WHAT HDR MEANS.
      High
      Dynamic
      Range

      Each word means something.

      RAW formats are NOT 12-bit.
      RAW formats are WHATEVER THE CAMERA SENSOR GRABS.
      8-bit. 10-bit. 12-bit. 14-bit. 16-bit. IT DOESN'T MATTER. And no, they are not HDR. They are simply a higher range than your shitty 8-bit jpegs. There is nothing DYNAMIC about them.

      NOBODY IS CONFUSING ANYTHING WITH TONE MAPPING.

      DYNAMIC has a MEANING.
      LOOK IT UP.

  5. Very impressive! by WilliamGeorge · · Score: 3, Interesting

    I've been a long-time fan of HDR photography, and was just thinking about ways that HDR could be implementing in video camcorders as well. Personally I'd like to see a correctly-exposed stream mixed in with the other two, as is common in photography, but even without that the effect is pretty darn cool.

    By the way, in case any camcorder manufacturers are watching, consider this idea: make a video camera with three (or more) times the required number of sensors for the resolution you want to record at. Set the logic in the device up to use three unique sets of sensors inside to pick up three different sets of images, at differing exposure settings. Then have them saved separately so that they can be integrated later on for various editing effects - or have a mode where they are integrated on-the-fly for easier use by non-professionals. I imagine it would be expensive to make such a complex sensor and camera, but it might be easier to manage than multiple cameras as the folks in the article did.

    --
    William George
    1. Re:Very impressive! by timeOday · · Score: 2, Insightful

      By the way, in case any camcorder manufacturers are watching, consider this idea: make a video camera with three (or more) times the required number of sensors for the resolution you want to record at.

      That's crazy. You'd get practically the same effect just by alternately under/over-exposing successive frames. From there you could interpolate whatever level of exposure you wanted without losing too much detail.

  6. Here I was thinking HDR video was old hat by scdeimos · · Score: 4, Informative

    Wasn't the first HDR video camera back in 1993? Granted, they called it Adaptive Sensitivity back then.

    1. Re:Here I was thinking HDR video was old hat by forkazoo · · Score: 2, Interesting

      Spheron had an awesome single-sensor HDR video camera demo at SIGGRAPH this year. It records 20 stops of latitude, and after some processing for debayering and whatnot, you get an EXR sequence. I got to see it live, in person, and stand a few feet away from the camera. The guy running the demo even let me play with some footage in Nuke on the demo laptop. I'm confused about why a hacked up beamsplitter based system would be so noteworthy, when the single-sensor method will suffer less light loss thanks to the simpler optical path.

      I'm sure the guys who did this project are proud of what they pulled off, and it's probably a neat hack, but I have to assume they are sort of operating in a vacuum if they think they have really invented something newsworthy.

  7. tried it out recently by frank_carmody · · Score: 2, Interesting

    I had my first foray into HDR still photography recently and I have to say I'm very very impressed with the results. Certain night-time scenes look absolutely stunning using 4-5 exposures. Here's some shots by a friend of a friend: http://roache7.deviantart.com/gallery/.

  8. Odd lighting issues by T+Murphy · · Score: 2, Insightful

    In the video, there is a part showing a man talking, and eventually he waves his arms around. At that point, you can see some parts of the picture become brighter near his arms- clearly not shadows, so it must be an artifact of the HDR processing. Anyone care to explain what might cause this, or how it might be addressed? I don't know much about HDR so I wouldn't have a clue, but some insight into the technical stuff behind the process would be interesting (and help people like me better learn and appreciate HDR).

    1. Re:Odd lighting issues by EnsilZah · · Score: 2, Informative

      I haven't noticed it and now it's been slashdotted so I can't confirm but I imagine that if they used two different exposures on the cameras then on the longer exposure a fast moving object would be blurred so at its core it would be darker because it's always blocking the light while at the edges it would be lighter since it's only blocking the light part of the time.
      So I guess it would create edge artifacts because of the mismatch between the short exposure which has less motion blur and is mostly at the same level of brightness and the long exposure which has the edge blurring.
      And I would think that you could solve that with a neutral density filter rather than using different exposure lengths.
      I'm this is all one big assumption though.

    2. Re:Odd lighting issues by arcsimm · · Score: 5, Informative

      The bright spots are indeed an artifact of the HDR process -- partulcarly the tone-mapping algorithms. On its own, HDR is basically a method of capturing intensity values that would otherwise fall above or beneath the threshold of a camera's sensitivity. The problem is, when yo do that you end up with image data that can't be completely represented within the gamut of a printer or a screen. You could simply display a "slice" out of the data, which results in a regular images at whatever exposure setting you've chose, or try to "compress" the tone values into your available gamut, which results in a washed-out appearance. This is where tone-mapping comes in. What tone-mapping does is try to compute the correct exposure levels on a per-pixel basis, by comparing its intensity relative to nearby pixels. Ideally, this results in shadows being brightened to the point where you can see detail in them, and blown-out highlights brought toned down (analogous to "dodging" and "burning" in terms of old-school darkroom film processing -- the dynamic range of film is much higher than that of photo paper).

      In practice, though, you end up with weird highlights around dark areas, like the ones you saw around the man's arms, because the tone-mapping algorithm is trying to maximize the local contrast in the image. It's brightened up the coat, and so it also brightens nearby pixels to compensate for the reduction in contrast. Some people try to adjust the algorithms to minimize this effect, while others try to maximize it for dramatic effect, or even an oversaturated, impressionistic look -- it's largely an artistic choice, though when done badly it can also be a sign of amateurism. Still others will manually composite multiple exposures to get the benefits of HDR imaging while avoiding its side effects entirely,

      The Wikipedia article on tone-mapping goes into great detail on the different approaches to HDR photography, if you're interested.

    3. Re:Odd lighting issues by icegreentea · · Score: 3, Informative

      You're seeing a moving halo effect. Most tone-mapping processes have trouble with dark on light transitions. Basically, in an attempt to 'smooth' out the transition between lightening/darkening, you get the lightening effect bleeding from the dark regions to the lighter regions creating a halo. If you watch the starting sequence with the buildings, if you look at the right side with one building in the foreground, and the dark side of another building in the background, you can once again see the halo effect. Just go google around HDR images, and you'll see it everywhere. It's very hard to get rid of, and simply put, if you run any tone-mapping process on default, you'll end up with them.

      It's basically the result of the software not being able to tell with confidence where the boundaries between higher/lower exposure is, so instead it assigns an approximate that "plays it safe" in one direction, and then smears out the boundary. Basically photoshop's magic selection wand + feathering.

  9. Re:HDR == High Dinamic Range by blai · · Score: 4, Funny

    TLS == three letter acronym

    Cool

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  10. Unimpressed by Ozan · · Score: 4, Informative

    The technique is promising, but the provided example video does not demonstrate a true advantage it has over conventional cinematography. They filmed with two cameras, one overexposing one underexposing, but they don't have one with the right exposure to compare with the composed HDR images. The city scenes are filmed at daylight, without any areas of high contrast that would make a high dynamic range necessary. The same with the people example, they even overdid it to give it a vibrant effect, making it more of an artistic tool than capturing shadows and lights naturally.

    They should make a short film with city nighttime and desert scenes, that should be impressive. They should also contact director Michael Mann, he would jump at the opportunity to film HDR.

    1. Re:Unimpressed by Anonymous Coward · · Score: 2, Insightful

      I'm unimpressed for a different reason.

      I think this is extremely interesting, and definitely worth reading about and watching.

      However, I just can't get into HDR. There was a point when HDR photography was sort of a novelty, interesting, but now I'm sick of it. Even when it's done well it looks odd, and I fear the same thing would eventually happen with video.

      I hope people take your perspective to heart, I really do. However, I anticipate this will be a dead end in much the same way it has become with still photography.

      I realize you're saying that this technique could be made more useful, but I've become so sensitized to HDR effects that any of it looks like a gimmick to me.

  11. True advancement in video technology by LoudMusic · · Score: 3, Insightful

    This is so much better than 3D technology. It's even better than high definition video. This is actually the process of creating better images. I am actually really excited about this!

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  12. Re:This is not HDR by black3d · · Score: 4, Informative

    Incorrect, it's true HDR recording. The process of viewing it on LDR/SDR monitors is tone-mapping, which over the years has been tuned to represent the best known science of what the eyes actually see at once - our retinas already make us susceptible to only being able to view certain ranges of light at a time.

    In other words, more information is being recorded than your eye can see at once, and you're complaining because when you see it, all that information isn't there? That's a pedantic, unsolvable contradiction.

    A true HDR *display* (unfathomably difficult to imagine, I won't begin to go into the problems with the source for all the light being in one location, while other light is also hitting the eye from the real-world outside of the display, making visual processing of the HDR display massively erronous), would offer no advantage to a tone-mapped image, as your eye still can't see more than a certain range at any given time.

    Tone-mapped SDR images actually produce images with more visible detail *at once* than the eye can distinguish *at once*. Sure, the eye can do things the still image can't, like focus somewhere else, shield out certain bright or dark parts, and readjust automatically to what you're now viewing - I'm not claiming tone-mapping will ever produce as much variance as the eye is capable of - but it DOES bring to light more detail in HDR recorded scenes than the eye could otherwise see at once looking at the same scene.

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  13. Franken/3D cameras by gmuslera · · Score: 4, Interesting

    With frankencamera you could do HDR and a lot more things in an "intelligent" camera with software. In fact the first implementation in a mass consumption device was in the N900, it takes several photos, regulates exposition and other parameters to make that photo in a more parametrizable way that the iphone could do. But not sure if that would be enough for HDR video, if needs that the input, in real time, have different something at hardware level. In that case maybe something like this 3D camera would be needed. And could give some meaning to such devices... not only shooting in 3d, but in HDR video.

  14. Watching the video by cvd6262 · · Score: 4, Funny

    Especially the part with the guy talking, made me think...

    So someone's found a way to make real life look life Half-Life 2 Episode 2?

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  15. Re:This is not HDR by black3d · · Score: 2, Interesting

    That's pretty much down to our mental training that a photograph is a realistic representation of lighting in a scene.

    This is similar to the mental effect which makes high frame-rate 60-90fps video look "fake" and less true-to-life to us, who have been watching 25fps movies for decades, despite the opposite being true.

    In truth, printed photographs are terrible representations of light and instead rely on our knowledge of the elements to trick our brain into viewing lit scenes in the context of previous experiences. Digital photographs, capable of being artificially lit are much better, but still not as good as real life.

    However, the best true-to-life representations of digital photographs is SDR tone-mapped HDR images. Look at the lights around you - your eyes DO see those blooms around lights, etc. Years of looking at standard photographs has trained us to believe that they're a great representation of real life - when they're not. They're simply the best we've been able to generally do.

    Besides, eventually HDR will be the norm, and this entire line of conversation will be moot. By that time, they will be "a normal photograph". In fact, HDR techniques have been practiced for a long time now - heavily since the 80s. Many of the "great" published photos of our times were taken with multiple exposure techniques - we might just not realize it because we only see the final result.

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    "The true measure of a person is how they act when they know they won't get caught." - DSRilk
  16. Re:This is not HDR by Animaether · · Score: 2, Informative

    A true HDR *display* [...] would offer no advantage to a tone-mapped image, as your eye still can't see more than a certain range at any given time.

    I don't think you would have said that if you'd seen the BrightSide display at Siggraph 2005..
    http://en.wikipedia.org/wiki/BrightSide_Technologies ..though I'll agree that ideally you'd have as little ambient light as possible, it was fine at the show floor with tons of different, flashing, lights around.

    I think I've noted it in a previous discussion on 3D displays... once they're done poking around at that, I'd love it if display manufacturers would go back to figuring out a way to make HDR displays cheaply along with industry-wide standards on how to address such displays.

  17. I did this on Fast and Furious/Tokyo Drift by Thagg · · Score: 3, Interesting

    For the third of the Fast and Furious movies, we had to film at night in the spectacular Shibuya Square in Tokyo, with its many animated billboards and video screens. I really wanted to get an HDR film of the billboards.

    For the driving green-screen sequences of the film, we had built a plate to mount three cameras, at 0, 45, and 90 degrees, to shoot panoramas driving down the street. To get the nodal points closer together, we had the cameras facing toward each other, with the lenses almost touching. It worked wonderfully.

    By taking the center camera out, and replacing it with a beam-splitter, we had a down-and-dirty HDR rig using the other two cameras. Now, this was HDR on film, not video -- but film already has a very high dynamic range -- so two cameras with very different effective exposures gave us a tremendous dynamic range. In the 'normal' exposure all of the brighter signs were blown out, but on the beam-splitter camera you could see all the details of the structure of the lighted billboards. Quite cool.

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