Using the Colorfront Film Grading Mode

This article covers features which are only available in Livegrade Studio.

Livegrade Studio supports the “Colorfront Film” transform of the Colorfront Engine. From Colorfront’s document “Using the Human Perceptual Model for Multiple Display Mastering”:

“The Colorfront Engine is a state-of-the-art parametric color processing pipeline mapping various input formats, including camera original (scene-referred) and graded (display-referred) images, to a wide range of SDR and HDR output formats at user definable brightness levels and gamuts while maintaining the creative intent.”

Using Colorfront Film with AJA FS-HDR

The Colorfront Engine implemented in AJA FS-HDR device can be controlled by Livegrade Studio. Setting up AJA FS-HDR for details on how to connect to FS-HDR.

The Colorfront Film Grading Mode

Livegrade Studio comes with a grading mode supporting all parameters of the Colorfront Film color processing pipeline.

The controls of the Colorfront Film grading mode

The controls are grouped into three sections:

CFE In: This section includes the input transform (for matching the incoming signal color space), scene-referred parameters (e.g. exposure and color temperature), and the grading color space.

CDL: This is a creative grading mode compatible with ASC-CDL. The ASC-CDL is applied in the color space selected as “Grading Colorspace”. 

Although the Colorfront Film color processing pipeline only supports one set of ASC-CDL, you can have more than one CDL nodes in the grading mode. All CDL nodes are combined into one set of CDL nodes when transferring look metadata for the Colorfront Film color processing pipeline.

Click “Edit” in the header bar of the grade controls to add additional CDL nodes or remove nodes.

CFE Look: In this section you can set additional creative parameters such as two independent looks (selection of a set of predefined looks), a blend factor between these looks, and an HDR amount.

CFE Out: This section holds all controls that define the output, such as output range and colorspace, a SDR preview and PQ output nit level for HDR output transforms.

The order of the mentioned sections cannot be changed.

Resetting Looks

When clicking “Reset Colors” in the bottom bar of the main window, or choosing “Reset Color Nodes Only” from the Grade menu, the following parameters are reset:

  • Exposure, Color Temp, Tint
  • All CDL and saturation nodes
  • Look selection and look blend
  • HDR amount

All other parameters stay untouched.

When clicking “Neutral” in the bottom bar of the main window, or choosing “Reset All Nodes To Neutral” from the Grade menu, all parameters are reset and the color processing pipeline set to Rec.709 input and output.

Transferring Look Metadata

Looks stored in the application’s shot and look library can be exported as CFE files for further processing in products capable of processing images in the Colorfront Film color processing pipeline.

See Exporting Look Metadata for more information on exporting CFE files.

Limitations

Using the proprietary Colorfront Film color processing pipeline has a few consequences for other features in the application. 

As the processing is happening in the FS-HDR, the application is currently only communicating and storing parameters for the color processing pipeline, but has no information about the actual color transforms.

This means that the following features are not working the same way as with non-proprietary color processing pipelines (such as LUT and CDL or ACES):

  • Processing of framegrabs and recorded clips in the viewer
  • Display of scopes of a captured live signal, framegrabs, and recorded clips
  • Exporting processed still images

You can work around a few limitations by capturing a pre-graded image (capturing the output of FS-HDR) in Livegrade Studio. See HD-SDI Signal Recording and Framegrabs  for information about capturing “LUT box output (graded)”.