Extracting multi layer exr

[kirang4e]

Hello,
Iam working on a 3D comp.
3 passes rendered in exr.
When I load it in Natron,It's not representing actual texture/color.
I could not understand how to extract them using shuffle node.Its not showing any layers inside.
(This shuffle node is confusing.A simple tut will be great.)
I selected passes In read node itself, but still its not reading correctly..showing blue dots.

It is working perfectly in nuke..

Here is the exr,which I used.
http://www.mediafire.com/download/lpbg7sv7lf7hlz2/art021.zip

Thank you.

[MrKepzie]

The blue channel seems heavily wrecked. I’ll try to see what happens, where did you produce that file ?

On 22 Jan 2015, at 10:20, kirang4e notifications@github.com wrote:

Hello,
Iam working on a 3D comp.
3 passes rendered in exr.
When I load it in Natron,It's not representing actual texture/color.
I could not understand how to extract them using shuffle node.Its not showing any layers inside.
(This shuffle node is confusing.A simple tut will be great.)
I selected passes In read node itself, but still its not reading correctly..showing blue dots.

https://cloud.githubusercontent.com/assets/10396656/5853097/d8e3edaa-a245-11e4-9c21-3f13867ba86e.png
It is working perfectly in nuke..

https://cloud.githubusercontent.com/assets/10396656/5853099/df88a826-a245-11e4-94e3-eaaa763e1db5.png
Here is the exr,which I used.
http://www.mediafire.com/download/lpbg7sv7lf7hlz2/art021.zip http://www.mediafire.com/download/lpbg7sv7lf7hlz2/art021.zip
Thank you.

—
Reply to this email directly or view it on GitHub #415.

[devernay]

It seems to be an OpenImageIO bug (I checked with OIIO's image viewer, iv, which give the same glitches).

exrdisplay works fine.

Probably because some components are float, and others are half, maybe @lgritz knows better about this.

Can you try to make the same image with all components float and/or all components half?

If it solves the issue, I'll file an OIIO bug.

chopper.exr:

file format version: 2, flags 0x200
cameraAperture (type float): 20.12
cameraFarClip (type float): 1e+30
cameraFarRange (type float): 1000
cameraFov (type float): 48.2144
cameraNearClip (type float): 0.1
cameraNearRange (type float): 0
cameraProjection (type int): 0
cameraTargetDistance (type float): 0
cameraTransform (type m44f):
   (0.71934 0.694658 1.49012e-08 0
    0.248943 -0.257788 0.933581 0
    0.64852 -0.671562 -0.358368 0
    13.4352 -17.5011 -5.71905 1)
channels (type chlist):
    A, 32-bit floating-point, sampling 1 1
    B, 32-bit floating-point, sampling 1 1
    Diffuse.A, 16-bit floating-point, sampling 1 1
    Diffuse.B, 16-bit floating-point, sampling 1 1
    Diffuse.G, 16-bit floating-point, sampling 1 1
    Diffuse.R, 16-bit floating-point, sampling 1 1
    G, 32-bit floating-point, sampling 1 1
    R, 32-bit floating-point, sampling 1 1
    Z Depth.B, 16-bit floating-point, sampling 1 1
    Z Depth.G, 16-bit floating-point, sampling 1 1
    Z Depth.R, 16-bit floating-point, sampling 1 1
compression (type compression): zip, multi-scanline blocks
dataWindow (type box2i): (0 0) - (1279 719)
displayWindow (type box2i): (0 0) - (1279 719)
gamma (type float): 1
lineOrder (type lineOrder): increasing y
pixelAspectRatio (type float): 1
screenWindowCenter (type v2f): (0 0)
screenWindowWidth (type float): 1
tiles (type tiledesc):
    single level
    tile size 64 by 64 pixels
type (type string): "tiledimage"

[kirang4e]

@MrKepzie Actually I downloaded it from a tutorial page,so we don't have much details about it's origin. :(
@devernay I checked metadata in nuke,It's 16-bit half float. I extracted them into separate layers and rendered individually. It's working 👍 . I checked meta data on individual layers,they all 16-bit half float only.

How can I separate them in Natron??

[blackearth2014]

Try creating three separate read nodes with the same file. Then change the channel components out. You should be able to see all three each connected to the viewer.

[kirang4e]

That I already did in 1st screenshot. please have a look :)

[devernay]

@kirang4e Nuke's metadata is wrong. The correct metadata is above (obtained using the official utility exrheader). This is very probably a bug with OpenImageIO.

[kirang4e]

@devernay Ok.Thank you. I learnt a small thing, exrheader ;).
I'm looking for another issue.How to extract multi layers in Natron? how to shuffle copy one pass to comp flow?

[MrKepzie]

As we did not yet implement multi-plane OpenFX suite, the only possible way for now is:

• Create multiple Read nodes to open the same file and read 4 different channels from each Read node
• Shuffle each Read node if needed

Don't worry internally, the same file will be read only once, it's just the pixel shuffling that will arise a bit more.

[kirang4e]

Ok.Thanks.Congrats for the Award :)
Can we expect multi-plane OpenFX suite in next version?

[MrKepzie]

Not sure but it's surely in the roadmap though

[devernay]

the bug was fixed in OIIO, see AcademySoftwareFoundation/OpenImageIO#1038

[prasanth3d]

hi which node can i use in Natron for the 'expression' node in nuke?Please help

[CameraRick]

SeExprSimple should do the trick