Applying Colour Management to Displayed Images

When you apply colour management to displayed images, the colours on the monitor or projector are affected but the underlying colour values of the clips' pixels are not changed.

The colour management for displaying images is based on the concept of "displays" and "views" as defined by an OCIO config file. In addition, the OCIO config may define viewing rules which allows the application to apply the appropriate viewing transform for media tagged with a given colour space. For example, a clip that is in a scene-referred space such as ACEScg or ARRI LogC4 should use a viewing transform that does tone-mapping such as ACES 2.0 SDR 100 nits. However, a clip that is already in a display-referred space such as Rec.709 does not need additional tone-mapping and only needs colour management for the given display it will be viewed on.

One characteristic of OpenColorIO to be aware of is that each display may have a different set of views defined in the config. For example, an SDR display may not contain the views that would only be appropriate for an HDR display. As such, it may occasionally happen that you have a viewport that is configured for one display and is requesting a view that only exists for other displays. For example, this might happen if your Scopes display is different than your Graphics Monitor display and you have Sync mode enabled. In this case you will see an error message in red text across the center of the viewport. The solution is to select another view for that viewport.

Specifying the Display Preferences

You specify which OCIO displays to use for various purposes in the Colour Management Preferences. These are workstation settings rather than project settings and are stored in the file: /opt/Autodesk/cfg/colour_mgmt_displays.cfg.

You may edit this file to automatically configure the application for a given workstation. This file may be moved to a different path by editing the colour_mgmt_displays entry in the file: /opt/Autodesk/cfg/<flame_version>/sysconfig.cfg.

The available settings in colour_mgmt_displays.cfg are:

• AutoSetGraphicsMonitor: This controls whether the Sync with OS button is enabled on macOS (true/false).
• graphicsMonitor: This is the name of the OCIO display to use for the graphics monitor.
• scopesMonitor: This is the name of the OCIO display to use for the scopes (i.e., the waveform monitors and vectorscopes).
• videoPreviewDevice: This is the name of the OCIO display to use for the video preview device (formerly known as the broadcast monitor).

If Sync with OS is true, the graphicsMonitor field is ignored and will contain a string from the ICC profile.

Note that whether the graphics monitor or video preview device is in HDR mode is controlled separately in the Flame Setup application. If HDR mode is enabled, the value for that monitor in the colour_mgmt_displays.cfg file is ignored.

If the requested display is no longer present in the OCIO config file, the first display in the config will be used as a fall-back.