From 901986cbf4b09b25cf0d54c07b205c5efc4d91be Mon Sep 17 00:00:00 2001 From: jpark37 Date: Sat, 15 Apr 2023 21:01:01 -0700 Subject: [PATCH] libobs,obs-filters: Align HDR to SDR disparity Adjust colors from BT.1886 to sRGB. --- libobs/data/color.effect | 10 ++++------ plugins/obs-filters/data/color.effect | 20 ++++++++++++++------ 2 files changed, 18 insertions(+), 12 deletions(-) diff --git a/libobs/data/color.effect b/libobs/data/color.effect index b60cb88e3..64af0c2ce 100644 --- a/libobs/data/color.effect +++ b/libobs/data/color.effect @@ -42,14 +42,12 @@ float3 rec2020_to_rec709(float3 v) return float3(r, g, b); } -float reinhard_channel(float x) -{ - return x / (x + 1.); -} - float3 reinhard(float3 rgb) { - return float3(reinhard_channel(rgb.r), reinhard_channel(rgb.g), reinhard_channel(rgb.b)); + rgb /= rgb + float3(1., 1., 1.); + rgb = pow(rgb, float3(1. / 2.4, 1. / 2.4, 1. / 2.4)); + rgb = srgb_nonlinear_to_linear(rgb); + return rgb; } float linear_to_st2084_channel(float x) diff --git a/plugins/obs-filters/data/color.effect b/plugins/obs-filters/data/color.effect index 1bc58bc96..47dd0c97c 100644 --- a/plugins/obs-filters/data/color.effect +++ b/plugins/obs-filters/data/color.effect @@ -8,6 +8,16 @@ float3 srgb_linear_to_nonlinear(float3 v) return float3(srgb_linear_to_nonlinear_channel(v.r), srgb_linear_to_nonlinear_channel(v.g), srgb_linear_to_nonlinear_channel(v.b)); } +float srgb_nonlinear_to_linear_channel(float u) +{ + return (u <= 0.04045) ? (u / 12.92) : pow((u + 0.055) / 1.055, 2.4); +} + +float3 srgb_nonlinear_to_linear(float3 v) +{ + return float3(srgb_nonlinear_to_linear_channel(v.r), srgb_nonlinear_to_linear_channel(v.g), srgb_nonlinear_to_linear_channel(v.b)); +} + float3 rec709_to_rec2020(float3 v) { float r = dot(v, float3(0.62740389593469903, 0.32928303837788370, 0.043313065687417225)); @@ -24,14 +34,12 @@ float3 rec2020_to_rec709(float3 v) return float3(r, g, b); } -float reinhard_channel(float x) -{ - return x / (x + 1.); -} - float3 reinhard(float3 rgb) { - return float3(reinhard_channel(rgb.r), reinhard_channel(rgb.g), reinhard_channel(rgb.b)); + rgb /= rgb + float3(1., 1., 1.); + rgb = pow(rgb, float3(1. / 2.4, 1. / 2.4, 1. / 2.4)); + rgb = srgb_nonlinear_to_linear(rgb); + return rgb; } float linear_to_st2084_channel(float x)