pub unsafe static kVTCompressionPropertyKey_PreserveAlphaChannel: &'static CFStringAvailable on crate feature
VTCompressionProperties only.Expand description
Instructs the encoder to encode or discard the alpha channel of input video frames
This property allows a client to specify whether or not the alpha channel in the source pixelBuffers should be encoded. The client may set this to kCFBooleanFalse in cases where they are not interested in preserving alpha, or if the alpha channel is known to be fully opaque. This property is not supported by all encoders.
See also Apple’s documentation