Function heif_sequence_encoding_options_copy 

pub unsafe extern "C" fn heif_sequence_encoding_options_copy(
    dst: *mut heif_sequence_encoding_options,
    src: *const heif_sequence_encoding_options,
)

Copy fields from src into dst, respecting both structs’ version numbers. Only fields present in min(dst->version, src->version) are copied, so this is safe when libheif and the caller were built against different header versions of heif_sequence_encoding_options. Pass NULL src to leave dst unchanged.