Static kVTCompressionPropertyKey_ContentLightLevelInfo 

pub unsafe static kVTCompressionPropertyKey_ContentLightLevelInfo: &'static CFString

Available on crate feature VTCompressionProperties only.

The value is 4 bytes containing a big-endian structure as defined in the Content Light Level Info SEI message.

The value will be set on the format description for output sample buffers, and incorporated into the appropriate SEI NAL unit where supported by the encoder.

See also Apple’s documentation