pub unsafe extern "C" fn swr_build_matrix2(
in_layout: *const AVChannelLayout,
out_layout: *const AVChannelLayout,
center_mix_level: f64,
surround_mix_level: f64,
lfe_mix_level: f64,
maxval: f64,
rematrix_volume: f64,
matrix: *mut f64,
stride: isize,
matrix_encoding: AVMatrixEncoding,
log_context: *mut c_void,
) -> c_int