I have two CIContexts configured with the following options:
let options1:[CIContextOption:Any] = [CIContextOption.cacheIntermediates: false, CIContextOption.outputColorSpace: NSNull(), CIContextOption.workingColorSpace: NSNull()];
let options2:[CIContextOption:Any] = [CIContextOption.cacheIntermediates: false];
And an MTKView with CAMetalLayer configured with HDR output.
metalLayer = self.layer as? CAMetalLayer
metalLayer?.wantsExtendedDynamicRangeContent = true
metalLayer.colorspace = CGColorSpace(name: CGColorSpace.itur_2100_HLG)
colorPixelFormat = .bgr10a2Unorm
The two context options produce different outputs when input is in BT.2020 pixel buffers. But I believe the outputs shouldn't be different. Because the first option simply disables color management. The second one performs intermediate buffer calculations in sRGB extended linear color space and then converts those buffers to BT.2020 color space in the output.