Static kVTVideoEncoderSpecification_RequiredEncoderGPURegistryID 

pub unsafe static kVTVideoEncoderSpecification_RequiredEncoderGPURegistryID: &'static CFString

Available on crate feature VTCompressionProperties only.

If set, the VideoToolbox will only use a hardware encoder running on the GPU specified by the provided GPU registryID.

This specification implies kVTVideoEncoderSpecification_EnableHardwareAcceleratedVideoEncoder. A separate hardware encode opt-in is not required. The GPU registryID can be obtained from a MTLDevice using [MTLDevice registryID] or can be obtained from OpenGL or OpenCL.

See also Apple’s documentation