DX – PY – Cube2LUT – ColorGrading

.CUBE to PNG LUT Workflow for GLSL Color Grading in Isadora

Description:

This Isadora demo project introduces a complete workflow for using industry-standard .CUBE LUT files in your GLSL-based color grading pipeline within Isadora. Built using the Pythoner actor and a custom GLSL shader, the patch allows you to convert .CUBE files into 2D PNG LUT textures, which can then be loaded natively into Isadora for efficient, real-time processing.

This system is ideal for users who want to apply professional color grading within live or interactive environments, without relying on external grading tools during playback.

It includes a number of useful User Actors.

• [NEW in Version 4] DX – PY – Create CUBE LUT – a powerful color grading utility that builds custom 3D LUTs by redefining the corners of RGB color space.
• DX – GLSL – Apply Lut to Video – (GLSL based, applies a LUT image to a video stream with numerous options)
• DX – PY – Load .Cube for Color Grading – (Python based, converts .cube files to LUT image)
• DX – PY – Browse for File (win+mac) – (Python based, opens a file browser and returns the full file-path)
• DX – PY – Save Video Frame as PNG – (Python based, allows the saving of a video frame as a PNG. Used here to save cube conversions for project inclusion)

Features (via included User Actors):

• 📁 Import and parse .CUBE LUT files using Pythoner.

• 🖼️ Auto-generate 2D PNG LUT images from .cube files compatible with GLSL shader to apply color grade.

• 🎨 Supplied GLSL shader demonstrates real-time color transformation using the generated LUTs.

• 🧠 Fully integrated within Isadora — no external software or plugin dependencies (* requires Pythoner virtual environment and modules).

• 💾 Save and reuse converted LUTs in any project.

• 📚 Includes a clean, modular patch structure to understand or extend the workflow.

Requirements (for DX – PY – Load .Cube for Color Grading):

• Pythoner custom virtual environment (watch the Tutorial below to learn about creating a virtual environment).
• 🧮 NumPy is required for LUT parsing.
  Install it into your Python environment via:
  pip install numpy
•  🧮 CV2 (openCV) is required for creating LUTs.
  Install it into your Python environment via:
  pip install cv2
• or the supplied Python scripts. Video Tutorial

Updates:

• v4 -adds ‘Create CUBE Lut’ scene, with User Actor that allows the creation of a custom 64^2 CUBE LUT as video output and/or PNG file.
• v2 -fixed save as PNG to use correct color order.
  -added improved comments to demo file