[Tig] IIF Status

Frank Hellmann frank at opticalart.de
Mon Dec 19 11:05:59 GMT 2011

Hi Cem, 

I haven't really had a chance to dig deeper into ACES/IIF. So treat my remarks with some care. 

> It all sounds good except that my only concern would be in fact the
> conversion when it comes to editorial. There would be too many steps
> for the material to get into editing. Editors are used to getting
> Prores' or DNxHD files that they can bring in and edit without
> having to convert or process and that is why DNxHD and
> (unfortunately) Prores has been so good (for them) to work with.
> Already, ARRI is planning on releasing the ability to record
> natively in DNxHD. So the question for editors would be "Why should
> I wait to get my material when I can work with the natively recorded
> DNxHD or Prores files?".

It really depends on your workflow. If you have a dailies grading session for the raw camera footage before it goes into editorial then there is not much of a difference. For feature films you will usually want this and I can't really imagine an editor being happy to work on like Arri LogC or even ungraded REC-709 material straight from the camera. The extra work comes into play, when you do the extra ACES compliant intermediate output after the dailies grade. So there is a bit of a work/rendering overhead in this, but I don't think it will impact the delivery speed to the editorial department. 

> Will the conversions you talk about need re-rendering of the Camera
> RAW or would these conversions be done on a GPU level where
> rendering would not be required through an accelerator card (a la
> Red Rocket)?

Rendering the ACES compatible output is just an extra color transform (usually device depended RGB to device independent XYZ colorspace) which is easily handled on the CPU or GPU. The big impact on rendering times comes from the debayer and postprocessing needed on most CameraRAW footage. So if you need to render RED Raw footage a Red Rocket card comes in handy for that part. 

Anyway, I was wondering how target colorspaces are handled in IIF? Assuming you would want your footage to have more or less the same look on all delivery formats (DCI P3 XYZ, HD Rec709, sRGB, Film Log...), it would be handy to reference that within the IIF container itself, so that all working stages (grading, vfx, titles...) exactly know which color limits (like a print film emulation lut) to apply. 

Are there any further publications or links available for the ACES/IIF specs? 

Best, Frank... 


Frank Hellmann 
Discover the World of MUNGO 

iPad meets Dailies 

OPTICAL ART Film & Special-Effects GmbH 
Waterloohain 6-8, 22769 Hamburg 
Tel: +49 40 51 110 51 , Fax: +49 40 431 69-499 

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