OpenImageIO
OpenImageIO copied to clipboard
AcademySoftwareFoundation
Feature request: improve sRGB parsing
Howdy all, a new beta version of Gaffer is out and it uses a newer version of OIIO. A number of us ran into a problem when the Gaffer launcher couldn't find an sRGB color space.
In my case I traced the problem to using a custom OCIO config and OIIO being unable to find the keywords it's looking for. My config's sRGB texture section originally read as follows:
name: sRGB texture
aliases: [srgb_tx, Utility - sRGB texture, srgb_texture, Input - Generic - sRGB texture]
OIIO couldn't parse this. I was able to fix the problem by either changing the name to sRGB - Texture or adding a new srgb alias. I should note that my config is based on the official ASWF CG config which also does not have an srgb alias.
It seems like one solution might be to add some more aliases from the ASWF config to OIIO's search: maybe srgb_tx and srgb_texture. Thank you!
I think the relevant details on the Gaffer side are :
- We're calling
ImageBufAlgo::colorconvert()to convert fromsRGBtolinear. - This worked OK with OIIO 2.4.11.0 and OCIO 2.2.1.
- It is broken with OIIO 2.5.8.0 and OCIO 2.2.1.
- The error is
Color space 'sRGB' could not be found. - Relevant Gaffer issue is here : https://github.com/GafferHQ/gaffer/issues/5695.
I had hoped that setting OIIO_DISABLE_OCIO would get us back to using OIIO's built-in sRGB->linear transform, but that doesn't seem to help.
Sounds like something is broken.
Do you have a way to trigger a symptomatic behavior using just OIIO? Like, given a particular OCIO config, is there a straight-up oiiotool command or short python script that will do something clearly wrong that I can use to track this down?
Yep, over on the Gaffer issue there's a config that shows the problem when used with this : OCIO=bhgc_v2.ocio oiiotool test.png --colorconvert sRGB linear -o test.exr. I don't think you need anything special in test.png- any old file will do I think.
Unless the problem is on the Gaffer side after all, I'd expect that to fail with OIIO 2.5.8.0 and OCIO 2.2.1.
I already patched that config to work with Gaffer 1.4. Here's the old one that showcases the issue:
ocio_profile_version: 2.1
environment:
{}
search_path: ""
strictparsing: true
luma: [0.2126, 0.7152, 0.0722]
name: bhgc_v2
description: |
Version 2024.2.2, February 26, 2024.
Simplified OCIO config for CG by Brian Hanke ([email protected]). Based on the new ASWF CG config.
To use, copy this file to a location of your choice and point your OCIO environment variable to it.
This work is licensed under CC BY 4.0. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
roles:
aces_interchange: ACES2065-1
cie_xyz_d65_interchange: CIE-XYZ-D65
color_picking: sRGB texture
texture_paint: sRGB texture
color_timing: ACEScct
compositing_log: ACEScct
matte_paint: ACEScct
data: Raw
rendering: ACEScg
scene_linear: ACEScg
file_rules:
- !<Rule> {name: Default, colorspace: ACES2065-1}
displays:
ACES:
- !<View> {name: sRGB, view_transform: ACES 1.0 - SDR Video, display_colorspace: sRGB - Display}
- !<View> {name: Rec.709, view_transform: ACES 1.0 - SDR Video, display_colorspace: Rec.1886 Rec.709 - Display}
- !<View> {name: Raw, display_colorspace: Raw}
inactive_colorspaces: [CIE-XYZ-D65, sRGB - Display, Rec.1886 Rec.709 - Display]
view_transforms:
- !<ViewTransform>
name: ACES 1.0 - SDR Video
description: |
Component of ACES Output Transforms for SDR D65 video
ACEStransformID: urn:ampas:aces:transformId:v1.5:ODT.Academy.RGBmonitor_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:ODT.Academy.Rec709_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:ODT.Academy.Rec2020_100nits_dim.a1.0.3
AMF Components
--------------
ACEStransformID: urn:ampas:aces:transformId:v1.5:InvODT.Academy.RGBmonitor_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:InvODT.Academy.Rec709_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:InvODT.Academy.Rec2020_100nits_dim.a1.0.3
from_scene_reference: !<BuiltinTransform> {style: ACES-OUTPUT - ACES2065-1_to_CIE-XYZ-D65 - SDR-VIDEO_1.0}
display_colorspaces:
- !<ColorSpace>
name: CIE-XYZ-D65
aliases: [cie_xyz_d65]
family: ""
equalitygroup: ""
bitdepth: 32f
description: The CIE XYZ (D65) display connection colorspace
isdata: false
allocation: uniform
- !<ColorSpace>
name: sRGB - Display
aliases: [srgb_display]
family: Display
equalitygroup: ""
bitdepth: 32f
description: |
Convert CIE XYZ (D65 white) to sRGB (piecewise EOTF)
AMF Components
--------------
ACEStransformID: urn:ampas:aces:transformId:v1.5:ODT.Academy.RGBmonitor_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:InvODT.Academy.RGBmonitor_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:ODT.Academy.RGBmonitor_D60sim_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:InvODT.Academy.RGBmonitor_D60sim_100nits_dim.a1.0.3
isdata: false
categories: [file-io]
encoding: sdr-video
allocation: uniform
from_display_reference: !<BuiltinTransform> {style: DISPLAY - CIE-XYZ-D65_to_sRGB}
- !<ColorSpace>
name: Rec.1886 Rec.709 - Display
aliases: [rec1886_rec709_display]
family: Display
equalitygroup: ""
bitdepth: 32f
description: |
Convert CIE XYZ (D65 white) to Rec.1886/Rec.709 (HD video)
AMF Components
--------------
ACEStransformID: urn:ampas:aces:transformId:v1.5:ODT.Academy.Rec709_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:InvODT.Academy.Rec709_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:ODT.Academy.Rec709_D60sim_100nits_dim.a1.0.3
ACEStransformID: urn:ampas:aces:transformId:v1.5:InvODT.Academy.Rec709_D60sim_100nits_dim.a1.0.3
isdata: false
categories: [file-io]
encoding: sdr-video
allocation: uniform
from_display_reference: !<BuiltinTransform> {style: DISPLAY - CIE-XYZ-D65_to_REC.1886-REC.709}
colorspaces:
- !<ColorSpace>
name: ACES2065-1
aliases: [aces2065_1, ACES - ACES2065-1, lin_ap0]
family: ACES
equalitygroup: ""
bitdepth: 32f
description: The "Academy Color Encoding System" reference colorspace.
isdata: false
categories: [file-io]
encoding: scene-linear
allocation: uniform
- !<ColorSpace>
name: ACEScc
aliases: [ACES - ACEScc, acescc_ap1]
family: ACES
equalitygroup: ""
bitdepth: 32f
description: |
Convert ACEScc to ACES2065-1
ACEStransformID: urn:ampas:aces:transformId:v1.5:ACEScsc.Academy.ACEScc_to_ACES.a1.0.3
isdata: false
categories: [file-io]
encoding: log
allocation: uniform
to_scene_reference: !<BuiltinTransform> {style: ACEScc_to_ACES2065-1}
- !<ColorSpace>
name: ACEScct
aliases: [ACES - ACEScct, acescct_ap1]
family: ACES
equalitygroup: ""
bitdepth: 32f
description: |
Convert ACEScct to ACES2065-1
ACEStransformID: urn:ampas:aces:transformId:v1.5:ACEScsc.Academy.ACEScct_to_ACES.a1.0.3
isdata: false
categories: [file-io, working-space]
encoding: log
allocation: uniform
to_scene_reference: !<BuiltinTransform> {style: ACEScct_to_ACES2065-1}
- !<ColorSpace>
name: ACEScg
aliases: [ACES - ACEScg, lin_ap1]
family: ACES
equalitygroup: ""
bitdepth: 32f
description: |
Convert ACEScg to ACES2065-1
ACEStransformID: urn:ampas:aces:transformId:v1.5:ACEScsc.Academy.ACEScg_to_ACES.a1.0.3
isdata: false
categories: [file-io, working-space]
encoding: scene-linear
allocation: uniform
to_scene_reference: !<BuiltinTransform> {style: ACEScg_to_ACES2065-1}
- !<ColorSpace>
name: sRGB linear
aliases: [lin_rec709_srgb, Utility - Linear - Rec.709, lin_rec709, lin_srgb, Utility - Linear - sRGB]
family: Utility
equalitygroup: ""
bitdepth: 32f
description: |
Convert ACES2065-1 to linear Rec.709 primaries, D65 white point
CLFtransformID: urn:aswf:ocio:transformId:1.0:OCIO:Utility:AP0_to_Linear_Rec709:1.0
isdata: false
categories: [file-io, working-space]
encoding: scene-linear
allocation: uniform
from_scene_reference: !<GroupTransform>
name: AP0 to Linear Rec.709 (sRGB)
children:
- !<MatrixTransform> {matrix: [2.52168618674388, -1.13413098823972, -0.387555198504164, 0, -0.276479914229922, 1.37271908766826, -0.096239173438334, 0, -0.0153780649660342, -0.152975335867399, 1.16835340083343, 0, 0, 0, 0, 1]}
- !<ColorSpace>
name: sRGB texture
aliases: [srgb_tx, Utility - sRGB texture, srgb_texture, Input - Generic - sRGB texture]
family: Utility
equalitygroup: ""
bitdepth: 32f
description: |
Convert ACES2065-1 to sRGB
CLFtransformID: urn:aswf:ocio:transformId:1.0:OCIO:Utility:AP0_to_sRGB-Texture:1.0
isdata: false
categories: [file-io]
allocation: uniform
from_scene_reference: !<GroupTransform>
name: AP0 to sRGB Rec.709
children:
- !<MatrixTransform> {matrix: [2.52168618674388, -1.13413098823972, -0.387555198504164, 0, -0.276479914229922, 1.37271908766826, -0.096239173438334, 0, -0.0153780649660342, -0.152975335867399, 1.16835340083343, 0, 0, 0, 0, 1]}
- !<ExponentWithLinearTransform> {gamma: 2.4, offset: 0.055, direction: inverse}
- !<ColorSpace>
name: Raw
aliases: [Utility - Raw]
family: Utility
equalitygroup: ""
bitdepth: 32f
description: The utility "Raw" colorspace.
isdata: true
categories: [file-io]
allocation: uniform
- !<ColorSpace>
name: sRGB neutral
family: Utility
equalitygroup: ""
bitdepth: 32f
description: For neutral input and output of images on sRGB - Display ACES 1.0 - SDR Video displays
isdata: false
categories: [file-io]
encoding: sdr-video
allocation: uniform
from_reference: !<GroupTransform>
children:
- !<DisplayViewTransform> {src: ACES2065-1, display: ACES, view: sRGB}
- !<RangeTransform> {min_in_value: 0., min_out_value: 0., max_in_value: 1., max_out_value: 1.}
- !<ColorSpace>
name: Rec.709 neutral
aliases: [Gamma2.2]
family: Utility
equalitygroup: ""
bitdepth: 32f
description: For neutral input and output of images on Rec.1886 Rec.709 - Display ACES 1.0 - SDR Video displays
isdata: false
categories: [file-io]
encoding: sdr-video
allocation: uniform
from_reference: !<GroupTransform>
children:
- !<DisplayViewTransform> {src: ACES2065-1, display: ACES, view: Rec.709}
- !<RangeTransform> {min_in_value: 0., min_out_value: 0., max_in_value: 1., max_out_value: 1.}