def pairwise_reconstructability(common_tracks: int, rotation_inliers: int) -> float:
    """Likeliness of an image pair giving a good initial reconstruction."""
    outliers = common_tracks - rotation_inliers
    outlier_ratio = float(outliers) / common_tracks
    if outlier_ratio >= 0.3:
        return outliers
    else:
        return 0