8 ms·

Temporally Coherent Local Tone Mapping of HDR Video

39 points by joubert 12y ago

ris 12y ago
I'm afraid I feel the same about results of this as I do with basically all attempts at tone-mapping. It makes the world look like a bad late-90s video game. Depths of light and darkness are what make a scene appear real. Maybe we just need to wait for HDR displays before we expect to see the full details of HDR imagery in a realistic way.
- wtallis 12y ago
  > "Depths of light and darkness are what make a scene appear real." But sometimes you also want to see what's going on. You don't have to turn the filter up to eleven. The fact that this filter performs so well even at exaggerated settings bodes well for its usability at tasteful, restrained settings. And it will probably make it a lot easier on cinematographers, so that they have to worry less about carefully lighting the set and can rely on being able to balance things out in post production.
  - ris 12y ago
    Tone-map me sceptical.
    - jonah 12y ago
      Where it benefits is trying to represent in video something perceptually close to how the eye/brain perceives a scene. It would have been nice to see some scenes with dialed down settings more "natural" results.
    - deleted 12y ago
      [deleted]
  - bashinator 12y ago
    Well they as much as admit that one of the demo scenes in that video looks fake because of the overuse of this technology. I personally think it's fascinating that they're finally hitting the uncanny valley from the other side.
- the_cat_kittles 12y ago
  its not the be all end all. its a cool effect achieved through some clever technical tricks.
- IshKebab 12y ago
  You're thinking of the terrible "photoshop effect" style tone mapping you often see, like [this monstrosity](http://fc01.deviantart.net/fs38/i/2008/313/2/6/Paris___Eiffel_Tower_V_WP_by_superjuju29.jpg http://fc01.deviantart.net/fs38/i/2008/313/2/6/Paris___Eiffe...). Obviously it isn't all like that. But when it's done well you shouldn't notice. Probably every time you notice tone mapping it is a bad example so you think all tone mapping is bad. The examples near the end of the woman driving, and exiting the tunnel were pretty amazing examples.
  - ris 12y ago
    The tunnel example was technically impressive, but I thought the woman driving video looked disgusting. It looks like poorly lit CGI.
- ANTSANTS 12y ago
  Tonemapping is an essential component of modern video editing and rendering, and for that matter it has been common in photo editing (through the processes of "dodging" and "burning" the film as it was being exposed) since at least the '40s. Tonemapping is what actually lets you see the depths of light and dark in the same scene without the darkest and brightest parts of the image being completely blown out to black/white. Our pupils control global contrast (average brightness for the entire image) and our retinas can account for some degree of local contrast, so not applying the tonemapping and having i.e. the view from a window appear blindingly white makes things look more unrealistic. (start at page 53) http://www.slideshare.net/naughty_dog/lighting-shading-by-john-hable http://www.slideshare.net/naughty_dog/lighting-shading-by-jo... http://mynameismjp.wordpress.com/2010/04/30/a-closer-look-at-tone-mapping/ http://mynameismjp.wordpress.com/2010/04/30/a-closer-look-at... https://en.wikipedia.org/wiki/Ansel_Adams https://en.wikipedia.org/wiki/Ansel_Adams The Disney Research team purposefully exaggerated their tonemapping far beyond what was aesthetically pleasing in order to clearly demonstrate the artifacts of other tonemapping techniques that their novel approach avoided. In an actual film, the editors would use much more subtle parameters.
  - ris 12y ago
    Ah - yes - but (to my eyes) there is a world of difference between artistic "tone-mapping" (Ansel Adams-style dodging and burning, I've done much of it myself) and algorithmic tone-mapping. The results are barely comparable to me.
    - ANTSANTS 12y ago
      Sure, no real-time algorithm can match what can be done by hand on a single image, but for video editing and real-time rendering, perfect manual tonemapping is expensive or impossible. You go with a flawed tonemapping algorithm, or you don't have any tonemapping at all.
- Renaud 12y ago
  I'm with you on the lack of taste shown by some lovers of the technique who push the local contrast to its more garish, vomit-inducing settings. Having said that, tone mapping is an essential photographic technique that has been used in one form or another since the beginnings of photography. It's purpose it to compensate for the poor dynamic range of the equipment or the picture's output media (paper, screen) and allow details in all brightness levels to be represented. As with most photographic techniques, tone mapping is best used when the effect doesn't overwhelms the final product.
- abandonliberty 12y ago
  Tons of high-end photography is tone-mapped these days. When done correctly, it works very well. The goal of this video wasn't to make it look good, it was to produce a technology that can HDR frames in a temporally coherent way. Further work is needed, but I strongly suspect that this will become a standard part of video editing.

39 points by joubert 12y ago

ris 12y ago

I'm afraid I feel the same about results of this as I do with basically all attempts at tone-mapping. It makes the world look like a bad late-90s video game. Depths of light and darkness are what make a scene appear real. Maybe we just need to wait for HDR displays before we expect to see the full details of HDR imagery in a realistic way.

wtallis 12y ago
> "Depths of light and darkness are what make a scene appear real." But sometimes you also want to see what's going on. You don't have to turn the filter up to eleven. The fact that this filter performs so well even at exaggerated settings bodes well for its usability at tasteful, restrained settings. And it will probably make it a lot easier on cinematographers, so that they have to worry less about carefully lighting the set and can rely on being able to balance things out in post production.
- ris 12y ago
  Tone-map me sceptical.
  - jonah 12y ago
    Where it benefits is trying to represent in video something perceptually close to how the eye/brain perceives a scene. It would have been nice to see some scenes with dialed down settings more "natural" results.
  - deleted 12y ago
    [deleted]
- bashinator 12y ago
  Well they as much as admit that one of the demo scenes in that video looks fake because of the overuse of this technology. I personally think it's fascinating that they're finally hitting the uncanny valley from the other side.
the_cat_kittles 12y ago
its not the be all end all. its a cool effect achieved through some clever technical tricks.
IshKebab 12y ago
You're thinking of the terrible "photoshop effect" style tone mapping you often see, like [this monstrosity](http://fc01.deviantart.net/fs38/i/2008/313/2/6/Paris___Eiffel_Tower_V_WP_by_superjuju29.jpg http://fc01.deviantart.net/fs38/i/2008/313/2/6/Paris___Eiffe...). Obviously it isn't all like that. But when it's done well you shouldn't notice. Probably every time you notice tone mapping it is a bad example so you think all tone mapping is bad. The examples near the end of the woman driving, and exiting the tunnel were pretty amazing examples.
- ris 12y ago
  The tunnel example was technically impressive, but I thought the woman driving video looked disgusting. It looks like poorly lit CGI.
ANTSANTS 12y ago
Tonemapping is an essential component of modern video editing and rendering, and for that matter it has been common in photo editing (through the processes of "dodging" and "burning" the film as it was being exposed) since at least the '40s. Tonemapping is what actually lets you see the depths of light and dark in the same scene without the darkest and brightest parts of the image being completely blown out to black/white. Our pupils control global contrast (average brightness for the entire image) and our retinas can account for some degree of local contrast, so not applying the tonemapping and having i.e. the view from a window appear blindingly white makes things look more unrealistic. (start at page 53) http://www.slideshare.net/naughty_dog/lighting-shading-by-john-hable http://www.slideshare.net/naughty_dog/lighting-shading-by-jo... http://mynameismjp.wordpress.com/2010/04/30/a-closer-look-at-tone-mapping/ http://mynameismjp.wordpress.com/2010/04/30/a-closer-look-at... https://en.wikipedia.org/wiki/Ansel_Adams https://en.wikipedia.org/wiki/Ansel_Adams The Disney Research team purposefully exaggerated their tonemapping far beyond what was aesthetically pleasing in order to clearly demonstrate the artifacts of other tonemapping techniques that their novel approach avoided. In an actual film, the editors would use much more subtle parameters.
- ris 12y ago
  Ah - yes - but (to my eyes) there is a world of difference between artistic "tone-mapping" (Ansel Adams-style dodging and burning, I've done much of it myself) and algorithmic tone-mapping. The results are barely comparable to me.
  - ANTSANTS 12y ago
    Sure, no real-time algorithm can match what can be done by hand on a single image, but for video editing and real-time rendering, perfect manual tonemapping is expensive or impossible. You go with a flawed tonemapping algorithm, or you don't have any tonemapping at all.
Renaud 12y ago
I'm with you on the lack of taste shown by some lovers of the technique who push the local contrast to its more garish, vomit-inducing settings. Having said that, tone mapping is an essential photographic technique that has been used in one form or another since the beginnings of photography. It's purpose it to compensate for the poor dynamic range of the equipment or the picture's output media (paper, screen) and allow details in all brightness levels to be represented. As with most photographic techniques, tone mapping is best used when the effect doesn't overwhelms the final product.
abandonliberty 12y ago
Tons of high-end photography is tone-mapped these days. When done correctly, it works very well. The goal of this video wasn't to make it look good, it was to produce a technology that can HDR frames in a temporally coherent way. Further work is needed, but I strongly suspect that this will become a standard part of video editing.