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  1. In Memory of LAJ_FETT: Please share your remembrances and condolences HERE

Info on ILM'S OpenEXR Files & H.P. 3 Trailer

Discussion in 'Fan Films, Fan Audio & SciFi 3D' started by JaredE, Nov 18, 2003.

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  1. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    Does anyone know anything about the ILM OpenEXR file format? I downloaded the plugin for photoshop and it works great!!! Does anyone know how to work it on AE it gives you the code to create it, and says that its freeware but im not that good at writing files. Here is the ilm link see if you can figure anything out it is very vague.
    http://www.ilm.com/latestnews.html
    Also check out this harrypotter trailer I think this is OpenEXR in the scene where Harry is in the tent with his wand and it goes from dark to super bright. This looks Awsome! Here is that tralier:
    http://harrypotter.warnerbros.com/web/dailyprophet/article.jsp?id=POA_Teaser_Trailer
     
  2. DeadEyesSmiling

    DeadEyesSmiling Jedi Youngling star 2

    Registered:
    Oct 4, 2003
    That trailer is awesome! I loved the Macbeth witches song. This looks like it'll be better than the last one...
     
  3. djr33

    djr33 Jedi Master star 4

    Registered:
    Apr 5, 2003
    i have no clue about your question sorry.

    but thanks for the link. i hadnt seen that before... :D
     
  4. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    This is sweet! Its amazing the results you can get with this format on photoshop. It makes the Brightnes/Contrast controls look so out of date!
     
  5. Shadow_of_Evil

    Shadow_of_Evil Jedi Grand Master star 6

    Registered:
    Nov 18, 2001
    EDIT: Markup wouldnt work :(
     
  6. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    gunna to try to create a 10 frame filmstrip and import into photoshop, and see if i can convert it to .exr and then paste it back on the filmstrip... let you know what happens
     
  7. Lots

    Lots Jedi Padawan star 4

    Registered:
    Dec 7, 2001
    makes you wonder

    is the filmstrip file as high definition as the HDRI image openEXR spits out?

    i wonder..

    also from the looks of it you need to know a bit of C++ to get it working right..
     
  8. Jedi2016

    Jedi2016 Jedi Padawan star 4

    Registered:
    Jun 3, 2000
    No, it's not.

    I must ask, though.. what would be the point of using OpenEXR in AE, anyway? Whatever video footage you bring in won't be in that format, and won't contain the extra information. In fact, you would need to create said EXR footage from scratch in a CG program or something, and then you might as well just adjust your lighting in CG rather than in Post.
     
  9. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    IT WORKED!!! notice the black backround on the same layer is still the same brightness! Looks good here is my test
    http://www.members.aol.com/obiejuankenobi/video/
    sorry i forgot to include the quicktime bar but file is small and only 10 frames so download to see its the exrtest or something like that file
     
  10. Lots

    Lots Jedi Padawan star 4

    Registered:
    Dec 7, 2001
    just did a little looking around on the site...

    found this: http://www.openexr.com/about.html

    apparently open exr is not the highest quality image you can use, however its probably more space saving than say.. a 32bit floating-point (thats decimal numbers:p) tiff which stores way more info than you probably get when you import from ur camera.. unless you've got some high end deal ;)
     
  11. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    To me the point of using this file is A-the controls and features that come with the plugin are sweet. And B-The quality is about 3 times better than using a btr/cnt adj. It looks like real light.
     
  12. MasterZap

    MasterZap Jedi Padawan star 4

    Registered:
    Aug 11, 2002
    Using OpenEXR without having High Dynamic Range data in the first place is comlpetely meaningless.

    However, if you are still silly enough to use "Brightness Contrast" (the most primitive control on the face of the planet) I understand you find it's options "useful".

    The reason is that OpenEXR's settings take into account the nonlinearity of light and how to map that into a linear light space, funk with it, and map back to the crappy 8 bit space we know and love, taking into account a bunch of psycho-optics and whatnot.

    However, you can get similar results by using Curves instead. I never touch brightness/contrast, but in 99.9% go for Curves.

    /Z
     
  13. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    your right about the curves.. but this still looks better. i tried to do it with curves and there is alot more distortion at high light

    and it looks to me that when you adjust the brightness in the curves it almost seems to create a layer of light over the image. This still looks much more real. It may be a waist of time but if there is no reason for it, why was it made
     
  14. AnakinGuy

    AnakinGuy Jedi Youngling star 2

    Registered:
    Sep 14, 2003
    Zap, or should I call you Sir...


    What do you use instead of brightness contrast? out of curiousity...



    Edit: never mind, I finished reading about the curves,

    BUT STILL! I'D LOVE A TUTORIAL FROM A FX GOD LIKE ZAP!!!
     
  15. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    AE effect/adjust/curves
     
  16. malducin

    malducin Jedi Padawan star 4

    Registered:
    Oct 23, 2001
    Well for starters, the trailer should go into the Lucasfilm Projects forum ;-). Second that shot in the tent could be done by mostly conventional means (practical plus something in post). ILM will probably be doing character animation (maybe Demetor shots and hypogriffs, maybe Quidditch match again). If you want better examples look at Hulk, Time Machine and other recent projects.

    its freeware ... see if you can figure anything out it is very vague

    If you want more info about OpenEXR you should check and subscribe to the mailing lists which are web accessible and where most of the activity occurs. Also it's not technically freeware but open source on a modified BSD license.

    however its probably more space saving than say.. a 32bit floating-point

    Yes because it's by default a 16 bit floating format. There might have been a post on the mailing lists that mentioned this could give them like 8 to 10 fstops (can't remember the exact number) of latitude so it's more than enough for most of their applications. It's also like NVidia Half format which means you can have interactive applications display and manipulate the images efficiently (say adjusting the exposure like on the OpenEXR viewer).

    Does anyone know how to work it on AE

    As Zap mentioned it's pointless unless you have captured in a high range format. In any case even if you had your footage that way it would be better to use Cinepaint which an handle filmstrips and has decent support (via a plugin I believe) of OpenEXR.

    The main use of OpenEXR now would be to capture lightprobes of your set or environment, build an OpenEXR map (environment) and render your CG elements with HDRI using the OpenEXR image. Splutterfish for example has released initial support for OpenEXR in Max (don't know if there is direct support in Brazil though) and the project has released a basic and reference display driver for the format for PRMan. Flay also released support for Lightwave. Other than that you would need a good coder. In that case you would probably be beter of using something like HDRShop with the Lightgen plugin.
     
  17. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    that makes since,, I understand that you will not get that high res. capture from a camera. But my question would be more for usuing this for a CG,3d,or photoshop that can produce an image good enough/ But since the plugin is for photoshop what file should you import the art as before you convert it over, a tiff i would think?

    EDIT: or is that junk compaired to a file rendered as exr
     
  18. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    ZAP-However, if you are still silly enough to use "Brightness Contrast" (the most primitive control on the face of the planet) I understand you find it's options "useful".

    No offence dude but you sound like that guy on the Simpsons who owns the comic book store :)
     
  19. Lots

    Lots Jedi Padawan star 4

    Registered:
    Dec 7, 2001
    *wonders why his post was mentioned*

    kinda redundant from what you said eh? :p

    anyway my point with that was there are other formats out there like the 32bit FP TIFF which can store more information than openEXR with its 16bit FP format..
     
  20. malducin

    malducin Jedi Padawan star 4

    Registered:
    Oct 23, 2001
    kinda redundant from what you said eh? :p

    Not really unless I totally misread it. After all you said that it would probably save space, when it's more like definately. Not only ituses half the numer of bits but OpenEXR also supports 3 compression schemes: RLE, ZIP and PIZ (developed by ILM, Rod Bogart I believe). In normal videos for the internet the savings my be neglible though (as compared to film resoltion). I wasn't sure if you were aware by the wording, no ofense or repeatage intended. You point is totally valid.

    or is that junk compaired to a file rendered as exr

    TIFF are actually one of the best and most flexible formats out there, hence why someone (Greg Ward?) developed a 32 bit fp format around it like Lots mentioned (ooops sorry dude there I go again ;-). It's probably the best way to go as far as building an OpenEXR from lightprobes.

    But my question would be more for usuing this for a CG,3d,or photoshop that can produce an image good enough/ But since the plugin is for photoshop what file should you import the art as before you convert it over, a tiff i would think?


    I believe the Photoshop plugin is only for reading and writing previously created EXR images. There is no way with the plugin to create an EXR image from a series of lightprobes (say in TIFF). Unless I missed an announcement though, but I doubt it.

    The only 2 practical ways to create EXR images (I mean non-highend) is to use Photogenics (cheap but not free) or Photoshpere by Greg Ward that only runs on Macs.

    (EDIT)

    Actually this was covered also in the mailing lists, there might be more gems in there but at the moment it's still a bit difficult. If only HDRShop was updated...

    how to get images in EXR format?
     
  21. JaredE

    JaredE Jedi Youngling star 2

    Registered:
    Nov 6, 2003
    yeah i would love to get my hands on Photogenics but its still like $800.00 and not really worth it.
     
  22. MasterZap

    MasterZap Jedi Padawan star 4

    Registered:
    Aug 11, 2002
    Actually, what y'all are "in love" with isn't the storage format itself (since you are starting from plain LDRI data), it's the nifty algorithem the OpenEXR people used to "squeeze" the high dynamic range imagery into LDRI.

    This algorithm, which uses a knee function not unlike an audio compressor, non-linearily maps HDRI to LDRI.

    Amusingly, this is VERY similar to what I was doing 10 years ago in my renderer RayTracker, which inherently did non-linear light-math (via a user definable spline function, no less). How the wheel turns ;)

    Its a typical problem with the fact that LDRI imagery, that we all known and love, go through so many layers of "nonlinearity" its not even funny. First we have gamma, then the way the human eye picks out color, then the errors in the display, etc....

    So the 8 bit data we all know is so far from linear it's not even amusing. The OpenEXR brightness squeeze doesnt simply scale the brightness and clamp to white (this looks very artificial and flat). It scales it, applies a knee compressor to it, and only mapps the very hottest data to *completely* white, and from the very hottest to fairly hot to a range of near-whites, and gently curves into a more linear mapping. All this is happening in the luminance realm (most curve functions work on RGB, not luminance/chrominance, and hence muck up the saturation since the R-to-G-to-B ratio changes)

    Incidentally this is very much like how our human eyes (and photographic film) actually "interpret" brightness. To our eyes, 1+1 does not equal 2, more like 1.3

    Alas, I ramble.

    One day, ILM should hire me so I could get my ancient RayTracker technology into their lighting pipe. It would rawk.

    Alas, I dream ;)

    /Z

     
  23. darthdastoli

    darthdastoli Jedi Master star 3

    Registered:
    Aug 4, 2000
    I have a non-OpenEXR question.

    What exactly is the difference between curves and levels. The way that we adjust brightness and contrast is by adjusting the shadows, midtones, and higlights in the levels controls, not curves. Is curves better? If so, how?
     
  24. Figrin-Dan_Man

    Figrin-Dan_Man Jedi Padawan star 4

    Registered:
    Nov 4, 2002
    I'm still learning all the little tricks of Curves, but there are tutorials out there.


    Curves is essentially the uber-leveler. You can adjust EVERYTHING from levels, and EVERYTHING from B/C.
     
  25. Joey__P

    Joey__P Jedi Youngling star 2

    Registered:
    Aug 18, 2003
    Geez! Was anyone else lost with Zap's post? I feel like I am in my first Algebra class. That was awsome!
     
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