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Exporting OpenExr


jojolimited

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I'm still not clear on exporting OpenEXR from A:M for use with other vfx programs. Any explanations would be helpful. (As in how to do it properly, hehehe).I'm currently playing around with Fusion5.1 learning edition (free). If I can get my head wrapped around this, A:M could be integrated into a production pipeline quite easily. sorry for the nube question.

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Unless I'm mistaken most Open EXR formats are compatible 'within' their own program.

Moving them back and forth between programs could get dicey.

From what I can tell the Open EXR standard is mostly standardized at its base format.

Once you start adding to it (and everyone seems to do that) you lose that standardization.

 

I'll recommend using Targa format to import into your other program and manipulate from there.

 

If you are a programmer you might be able to work a better conversion.

 

I don't want to say you can't move Open EXR files back and forth but from what I've seen that been largely true.

The format doesn't seem to be designed for portability as much as extensibility.

 

Having said all this (without really knowing) I'd like to know more about Open EXR myself but my interest is mostly for leveraging the format for internal A:M usage.

 

You can read more about OpenEXR here:

 

http://www.openexr.com/

 

I hadn't realized that OpenEXR recently won an Academy Award. Cool.

Info taken from the linked site:

 

January 4, 2007 - OpenEXR wins an Academy Award for Technical Achievement.

 

The Academy of Motion Picture Arts and Sciences today announced the 15 winners of Scientific and Technical Academy Awards. A Technical Achievement Award goes to Florian Kainz for the design and engineering of OpenEXR, a software package implementing 16-bit, floating-point, high dynamic range image files. Widely adopted, OpenEXR is engineered to meet the requirements of the visual effects industry by providing for lossless and lossy compression of tiered and tiled images.

 

Congratulations to all for making OpenEXR such a success!!!

Information related to compatibility:

The current OpenEXR version number is 2. (Version 1 was used internally by ILM before OpenEXR was

released as open source. The IlmImf library can no longer read or write version 1 files.)

 

Not that anyone outside of ILM is using version 1 files.

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Thanks, I've read up on OpenEXR. It supports 16 and 32 bpc color. There are other 3d programs that export/output standard exr files that can be read by other programs. The options available are that even if A:M only supported rgba, they could still render out multiple layers with alpha channel into a single exr file, or multiple exr files each with different aspects. Fusion, Nuke, AE and soon others are using openExr for vfx compositing.

Unlike the polygon modellers and animation programs, Hash with spline and patch is resolution independent. Whether it's for SD, or 2K one size adapts to all. yes A:M uses some of it's own exr extensions for internal compositing, that doesn't mean they couldn't export in a publicly usable standards based version.

Anyway, making a formal request, knowing full well Hash has got a lot of things on their plate.

 

btw, for what it's worth, I've been talking to working pros using LightWave and XSI and they have a lot of respect for A:M. Seems only the fanboys, wannabes and the clueless are taking shots at it. I strongly feel if a:m can somehow get a renderer than can compete with the likes of Vray, they will be back in the game big time from a perception point of view. I don't say that lightly either and don't expect something like that in the immediate future.

I've recently downloaded a freeware renderer name 'Kerkythea' that does GI/Raytracing and supports output from Blender, 3dstudio and of all things Google Sketchup. They have an xml based import/interface. Wondering if a:m could adapt to something like that. It's free and open source and a little gem that doesn't get a lot of attention. Search Google, I won't post a link here out of respect.

 

The single biggest issue I've run into is people thinking A:M is an island. Not really true, but perception is different.

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Increasing numbers of programs support OpenEXR nowadays, and at the high end level, most can support it.

 

The problem is that when multiple layers are used in OpenEXR, there is no standard for how the multiple channels are defined and so most programs that support OpenEXR will read the top layer and ignore everything else.

 

A:M outputs 16 bit channels, but it is important to make it clear that these are 16 bit floating point numbers which means 10 bits of actual colour resolution per channel, one sign bit, and 5 bit for the exponent. That probably really is sufficient for most purposes - especially if the target is for DVD format with its 8 bit resolution per channel.

 

I would always render out to OpenEXR now instead of TGA's because with OpenEXR it takes the same time, but you definitely get more out of the rendering time. If I need TGA's, then I can always get A:M to convert them, or use the free XNView package to batch convert them to any other 8 bit format in an instant.

 

XNview is like Irfanview that many people may know, but it has the extra benefit of supporting OpenEXR that is something Irfanview cannot do. There is of course only one file manager in the world - TotalCommander, and since it supports XNView integration, coping with OpenEXR images is a breeze.

 

I do think a simple batch utility that can extract layers from an A:M OpenEXR light buffer render to seperate OpenEXR images would be very useful, and when I finish some plug-in programming, I will give it a go.

 

One of the beauties of OpenEXR is that everyone using the format is using the same OpenEXR source code or libraries, so that the compatibility of the format between different applications that support it is absolutely excellent. Everyone usually supports every one of the compression formats. Typically, OpenEXR support by older 8-bit only graphics applications never works to well, but the newer packages that do support floating point colors channels or at least 16 bit integer channels usually support single layer OpenEXR very well. Most of the "compatibility" issues I have seen with OpenEXR relvolve around 8 bit graphics apps that choose to convert from 10 bit floats to 8 bit integer in very odd ways - perhaps they are trying to compress the fulldynamic range of the OPENEXR images down into 8 bit intger range which results in washed out looking images.

 

Edit in floating point and the problems are solved.

 

Every one of the OpenEXR compression formats is completely lossless for A:M renders - even the lossy option in OpenEXR is lossless for the A:M resolutions. This means you cannot really go wrong with the format.

 

Also OpenEXR make fabulous decals for A:M to use, especially for displacement and bump maps. If you are getting A:M to generate decals for A:M to use, then OpenEXR is the only way to go. It is not just the extra 2 bits of real resolution, it is the fact that A:M actually does properly support the floating point displacements so you can get displacements much bigger then 1.0 (equivalent of 255 in an TGA channel).

 

It really is a superb format for movies and animation. It doesn't have the compatibility problems of, say, the Tiff format. The Tiff format does have almost every capability you can imaging (except for multiple layers), but how many programs can actually understand all of these capabilities? The negatives of using OpenEXR really revolve around the older generation of 8 bit graphics programs and low end 8 bit video programs that do not support it, and that is only a short term problem. It is an open format, and most of the alternatives are actually not open formats. The proprietry formats often have licensing issues, limited flexability and since everyone is writing their own different libraries, there are real compatibility problems.

 

I think OpenEXR is an inspired choice of format by Hash and I think within a couple of years, I think the choice will prove to be absolutely correct.

 

Richard Harrowell.

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Thanks for that info.

I've been meaning to move toward OpenEXR for some time now but have enjoyed Targa so much its been hard to break the habit.

You are right in that it should be easy to move from OpenEXR to Targa so... maybe its time to make the move.

 

I'm still a bit wary and probably will be until I experiment and test.

I assume/hope the alpha channel is retained in the conversion from OpenEXR to Targa?

(Easy enough to test)

 

I agree that the benefits of Open EXR are many.

Time to leverage that I think.

 

This then begs the question... why not use EXR format for TWO?

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I assume/hope the alpha channel is retained in the conversion from OpenEXR to Targa?

(Easy enough to test)

 

If you convert with XNView, the alpha channel is preserved.

 

I agree that the benefits of Open EXR are many.

Time to leverage that I think.

 

This then begs the question... why not use EXR format for TWO?

 

Probably too many old 8 bit graphics apps. The trouble is that all the graphics plugins were written for 8 bit and it will take time for everything to be replaced with floating point versions. So with TGA's, you can put renders straight into Virtualdub and you have temporal filters, blur, crop - you name it. Same with lots of the favourite photohop plugins that people have collected over the years.

 

Even if I was going to use 8 bit programs, I would still render in OpenEXR and then convert the renders in XNView.

 

Sorry to MAC users if I keep mentioning all this Windows software, but you are luck enough to have Cinepaint available - OpenEXR support, layers, full set of floating point image tools, frame buffer, scripting, cloning between different frames, etc. Its going to take ages for the Windows version of Cinepaint to become useable.

 

Richard Harrowell.

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If you convert with XNView, the alpha channel is preserved.

 

I was thinking more about internal conversion in A:M.

Have you tested that?

 

The main reason I use Targa is to gain the benefit of the alpha channel.

If its an easy move from EXR to Targa within A:M while retaining that... I'm there.

 

As of tonight I'm there anyway but would need to make allowances.

 

Edit: EXR converted to Targa w/ alpha channel in A:M just fine.

Most outstanding.

 

For JoJo... If for any reason you cannot get EXR over into your other application you can convert from EXR to Targa in A:M and then use them.

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Fusion 5.1 directly supports AM OpenEXR files.

Add a loader and then click on the format tab.

Under the RGBA tabs select the channel that you wish to use EG AmbienceR, AmbienceG, AmbienceB and AmbienceA.

For the next layer of the OpenFX Tab add another loader and then select the Keylight layers in the same manner.

Works like a charm.

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Fusion 5.1 directly supports AM OpenEXR files.

Add a loader and then click on the format tab.

Under the RGBA tabs select the channel that you wish to use EG AmbienceR, AmbienceG, AmbienceB and AmbienceA.

For the next layer of the OpenFX Tab add another loader and then select the Keylight layers in the same manner.

Works like a charm.

 

Fusion can actually read multilayer OpenEXR? That is very useful to know.

 

Definitely, very few programs even attempt to read multilayer OpenEXR's at the moment.

 

Richard Harrowell.

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XNview is like Irfanview that many people may know, but it has the extra benefit of supporting OpenEXR that is something Irfanview cannot do. There is of course only one file manager in the world - TotalCommander, and since it supports XNView integration, coping with OpenEXR images is a breeze.

 

Hi Richard.

I have just installed XNview and I cannot find an option to import EXR files (only HDRI). Are you sure it works or did I missed something?

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JonArtbox, that's good to know. I downloaded the learning version of Fusion 5.1 and will have to try that. Fusion supports up to 32bpc float so A:M 16bit float should work fine. This is really great news. Now I have to look up that compositing tutorial and reaquaint myself.

For those who don't know, the learning edtion of fusion is free. You can go to eyeonline.com to find the details. The commercial version is expensive, but it's considered an industry standard for film and high end hd work.

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I thought I'd try HAMRviewer to see if it would display EXR images.

I seem to be getting EXR files in HAMRviewer but not in all cases.

 

I've been moving back and forth from v13 to v14 a lot and that would seem to indicate .PRJB files exported out of v14 don't display the EXRs in HAMRviewer. Also the EXR's alpha channels aren't supported.

It may be that the EXR files get converted to another format upon export?

That shouldn't be the case as they are external files.

Easy enough to test by replacing the image I guess.

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Sorry to be worried, but once upon a time there was this great thing called Multiplane....

And with the compositing section from the previous forum gone.....

 

Multiplane isn't going anywhere soon. Its largely been assimulated in other graphics definitions and terms.

As pioneered by Disney it was a new and promising technology but its not so much a technology anymore as it is a technique.

 

One of the reasons you don't see it mentioned as often is that when you can create worlds in three dimensions you don't always need a technique that creates the illusion of 3D within multi-planes.

 

The art of multiplane has fallen out of favor in the world of 3D but its very much alive and well in the realm of 2D, especially in post production and special effects.

Every time someone uses layers in Photoshop they are using a derivative of multiplane.

Similarly, OpenEXR is a technological extension of multiplane that allows manipulation of the multiple planes of images held within a single image.

Its main technological advantage is that it can be manipulated programatically through C++.

 

Once created, you no longer need to locate, collate and order the various layers of images because they are already there contained in one file.

 

Like any image format OpenEXR can be supplanted when something better comes along.

TIF images for instance can do much of the same thing as EXR and in some ways more.

Until it is replaced the EXR format has George Lucas, Industrial Light and Magic and a lot of motion picture compositing and effects to keep it going.

That should be a good long while.

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Like any image format OpenEXR can be supplanted when something better comes along.

TIF images for instance can do much of the same thing as EXR and in some ways more.

 

OpenEXR is much better from the purposes of film/animation then Tiff. Forgetting the huge compatibility problems of Tiff, Tiff cannot handle multiple layers and it cannot handle 16 bit floats (which is all you need for animation or movies).

 

Tiffs have things like 32 bit floating point channels and 64 bit integer, but so what ? - nothing around can seriously make use of that resolution. You just end up storing twice or four times as much data, but no extra content.

 

All of the OpenEXR compresison formats are lossless or close enough to lossless so it doesn't matter - -again this is perfect for renders or post production intermediates.

 

I think it is very lucky there is at least one good image type. OpenEXR is a format crafted to precisely fit the needs of movie and animation work so why would you want to look to other formats, particularly closed source proprietry formats (lie all the alternatives are).

 

Richard Harrowell.

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Rodney, I think Jojo's refering to Hash's Multiplane Compositing module which was released back version 6 or so. It was a fantastic piece of software, some of which was integrated into AM proper with image layers.

JoJo I think you're safe, although the more people who use composite and OpenEXR, the better.

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Hi Richard.

I have just installed XNview and I cannot find an option to import EXR files (only HDRI). Are you sure it works or did I missed something?

 

Same here. Perhaps a plugin needs to be installed?

 

 

There was something that had to be done from memory. Do you have a file IlmImf.dll in the plugins folder? If you do, then you have OpenEXR support in XNView.

 

Have you gone to Tools->Options->Associations and ticked "OpenEXR" (if you use "view as name" mode or "exr" if you use "view as extension" mode?

 

Richard Harrowell.

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btw, Rick, OpenEXR is directly supported on the latest Nvidia grahics cards. They helped ILM to develop it.

 

I am not sure it does anything that will help us, unless you are going to get into very serious programming. To access the nVidia features, you have to use libraries that are currently only in the nVidia SDK (several hundred of mBytes to download). I am not sure nvidia licensing lets you distribute the libraries so I think everyone has to download the rediculous SDK.

 

As a result, most programmers do not use the nVidia enhancements.

 

Richard Harrowell.

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Rodney, I think Jojo's refering to Hash's Multiplane Compositing module which was released back version 6 or so. It was a fantastic piece of software, some of which was integrated into AM proper with image layers.

 

John,

Hash's Multiplane was the primary reason I upgraded to Netrender back in v9 timeframe.

I found I didn't need Netrender for that purpose however as much of Multiplane had been incorporated into A:M as you state.

If only 'some' of Multiplane was integrated into A:M this does beg the question then... what didn't make the transition?

Having never used the old A:M Multiplane module I don't have anything available for comparison purposes.

 

My response to Jojo was taking the long way around to answer the underlying question of 'where is multiplane'?

Many (most?) A:M Users don't even know what multiplane is much less how to effectively use the process in A:M.

As far as I can tell everything available in the old multiplane is available to us now via Rotoscope, Layers and Compositor.

Again though I have no reference to base an informed opinion.

 

Rich,

I dowloaded the OpenEXR plugin from the XNView site... works like a charm. (not sure how I missed seeing it... perhaps they could alphabetize the list... or I could get glasses) ;)

 

Very nice. (alas Irfanview your glory days are fading)

 

Caroline,

The EXR plugin for XNview does view but it also allows conversion which is probably why most will want to plug it into their workflow.

It helps also for that quick previewing outside of A:M of course too and for sharing with others that might want to see the unconverted EXRs but don't own A:M. To get to the power of EXR's format we'll need to use programs like A:M.

 

Thanks for pushing me in this direction everyone.

My move to EXR has been too long in coming.

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  • 2 weeks later...

Just catching up on this old thread--- wow, lotta info!

 

I heard some gossip today that one of the 'big houses' here in D-town (Detroit) is shipping off their Flame and will replace it with several seats of 'Nuke'. I had to scramble to learn what Nuke is...(Digital Domains proprietary compositing software, yet to be released.) The main reason being that Nuke makes good use of .exr's...

 

Anyone hear about Nuke's release date? There's SURE not much about it on Google.

 

Looks like it's high time to get going on the A:M .exr route...it's available in V13 right?

Any good links to 'get up and running' tutorials???

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One of the easiest ways to explore EXR is to just render out to it and experiment.

 

I recommend rendering out a simple (but lighted!) animation to a sequential set of EXRs.

Bring those back into A:M via Right Clicking on Images container in the Project Workspace.

Once in A:M Right Click again and select Build Composit.

 

This still won't be quite enough to see many results.

For that you'll want to add a Post Effect or two... three... four.

 

Go under a subcontainer that is identified with Mix for instance.

Right Click and add a Exposure Post Effect

Then change the Exposure over time.

 

You should get a simple example of the that effect.

 

I would review the tutorial and information at the previous Feature Focus link before diving in too deep.

It'll help tremendously.

 

Please share what you find out with us!

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