Static kVTCompressionPropertyKey_UsingHardwareAcceleratedVideoEncoder 

pub unsafe static kVTCompressionPropertyKey_UsingHardwareAcceleratedVideoEncoder: &'static CFString

Available on crate feature VTCompressionProperties only.

If set to kCFBooleanTrue, a hardware accelerated video encoder is being used.

You can query this property using VTSessionCopyProperty after you have enabled hardware accelerated encode using kVTVideoEncoderSpecification_EnableHardwareAcceleratedVideoEncoder to see if a hardware accelerated encoder was selected.

See also Apple’s documentation