Function estimate_inter_costs 

pub(crate) fn estimate_inter_costs<T: Pixel>(
    frame: Arc<Frame<T>>,
    ref_frame: Arc<Frame<T>>,
    bit_depth: usize,
    frame_rate: Rational32,
    chroma_sampling: ChromaSampling,
    buffer: Arc<RwLock<[FrameMEStats; 8]>>,
    cpu_feature_level: CpuFeatureLevel,
) -> f64