Static kVTDecompressionPropertyKey_AllowBitstreamToChangeFrameDimensions 

pub unsafe static kVTDecompressionPropertyKey_AllowBitstreamToChangeFrameDimensions: &'static CFString

Available on crate feature VTDecompressionProperties only.

True if decoder is allowed to output buffers matching reduced frame dimensions in the bitstream rather than under-filling them.

This is an optional property only supported by video decoders for bitstream formats which have a provision for specifying output dimensions per-frame, such as AV1.

If a decoder does not support this property or if the property value is set to kCFBooleanFalse, all decoded frames will have the same dimensions as specified in the format description. In this case, if the bitstream changes the frame dimensions, the output buffer will be padded to the dimensions specified in the format description.

When this property is set to kCFBooleanTrue, the decoder will set the dimensions of each output buffer to match the dimensions specified in the bitstream for that frame.

In all cases, output buffer dimensions will never exceed the dimensions specified in the format description.

In apps linked to SDK versions before this property was added, the AV1 decoder will behave as if this property is set to kCFBooleanFalse. Otherwise, value of this property defaults to kCFBooleanTrue where supported.

See also Apple’s documentation