More tone mapping

[natural-harmonia-gropius]

• [x] ITU-R BT.2408 aka BT.2390 EETF
• [x] ITU-R BT.2446 Conversion Method A (Philips?) & C (NHK), B has no specific implementation
• [x] SMPTE ST 2094-10 Dolby (Dolby Vision doesn't use this)
• [ ] SMPTE ST 2094-20 Philips, basically BT.2446A
• [x] SMPTE ST 2094-30 Technicolor, no specific implementation
• [ ] SMPTE ST 2094-40 Samsung (HDR10+?)
• [ ] T/UWA 005.1 HDR Vivid
• [x] Gain Map (libultrahdr) uses Reinhard
• [x] Android (libtonemap) 13 here, Oreo was removed due to no benefits.
• [x] Browser Chrome uses Reinhard, Safari uses BT.2390
• [ ] PBR Neutral
• [ ] Minimal AgX Implementation
• [ ] AMD FidelityFX HDR Mapper The modern alternative to Lottes(?)
• [ ] ACES 1.3 here, take a look at ACES 2.0
• [ ] ARRI REVEAL (AWG4 + per-channel K1S1?)
• [ ] HLG with Lw=203 (?)

[geextahslex]

Have you thought about spline?