Static kVTVideoDecoderSpecification_RequiredDecoderGPURegistryID 

pub unsafe static kVTVideoDecoderSpecification_RequiredDecoderGPURegistryID: &'static CFString

Available on crate feature VTDecompressionProperties only.

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

This specification implies kVTVideoDecoderSpecification_EnableHardwareAcceleratedVideoDecoder. A separate hardware decode 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. This option can only be used to specify a GPU registryID corresponding to a removable GPU (eGPU). If 0 is specified for the required GPU registryID, the VideoToolbox will not utilize removable GPUs for decode.

See also Apple’s documentation