OpenDRT v0.0.80

[jedypod]

This is a big change with a lot of development work compared to v0.0.75. Here is a summary of the notable new features:

Tonemap

• Replace tonemapping function with a piecewise hyperbolic compression function with power and parabolic toe compression.
  See this desmos plot for details on the math.
  And if you're curious about other options and a verbose history of the development, check out these posts on the acescentral thread. In particular, this one and this one.
• First pass model and presets for HDR displays

Chroma Rendering

• Switch to using a "weighted vector length" norm. This allows a massive complexity reduction while preserving the nice rendering features I was trying to achieve with much more complex methods before:

  • More saturated colors especially blues and reds render darker, while yellow and orange renders brighter
  • Saturation boosted along the red/blue axis while keeping magenta and yellow under control

• Switch the rendering colorspace to Truelight LMS, described in Chromaticity coordinates for graphic arts based on CIE 2006 LMS with even spacing of Munsell colours by Richard Kirk.

• Apply chromatic adaptation for white-point handling as LMS scales in the rendering colorspace.

• Calculate whitepoint normalization factor based on whitepoint and output display gamut, and concatenate with other output domain scale elements

• Add inverse transform

• Completely rework and massively simplify InverseEOTF and EOTF nodes

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This discussion was created from the release OpenDRT v0.0.80.