pub unsafe static kVTCompressionPropertyKey_TargetQualityForAlpha: &'static CFStringAvailable on crate feature
VTCompressionProperties only.Expand description
The target quality to use for encoding the alpha channel.
The desired compression level to use for encoding the alpha channel. This value should be specified as a number in the range of 0.0 to 1.0. 0.0 is lowest quality and 1.0 implies nearly lossless. Alpha plane bit rates will tend to increase with increasing values. When encoding the alpha channel, quality is given priority over bitrate. Note this parameter is currently only applicable to HEVC with Alpha encoders.
See also Apple’s documentation