pub unsafe static kVTCompressionPropertyKey_SpatialAdaptiveQPLevel: &'static CFStringAvailable on crate feature
VTCompressionProperties only.Expand description
Control spatial adaptation of the quantization parameter (QP) based on per-frame statistics. If set to kVTQPModulationLevel_Disable, spatial QP adaptation is not applied based on per-frame statistics. If set to kVTQPModulationLevel_Default, video encoder is allowed to apply spatial QP adaptation for each macro block (or coding unit) within a video frame. QP adaptation is based on spatial characteristics of a frame and the level of spatial QP adaptation is decided internally by the rate controller.
This property must be disabled when low latency rate control is enabled. Support for this property is codec dependent.
See also Apple’s documentation