pub unsafe static AVVideoExpectedSourceFrameRateKey: Option<&'static NSString>Available on crate feature
AVVideoSettings only.Expand description
Indicates the expected source frame rate, if known.
The frame rate is measured in frames per second. This is not used to control the frame rate; it is provided as a hint to the video encoder so that it can set up internal configuration before compression begins. The actual frame rate will depend on frame durations and may vary. This should be set if an AutoLevel AVVideoProfileLevelKey is used, or if the source content has a high frame rate (higher than 30 fps). The encoder might have to drop frames to satisfy bit stream requirements if this key is not specified.
See also Apple’s documentation