def _get_contain_size(src_img_size, dst_img_size):
    """Get image size which fit `dst_img_size`.

    Args:
        src_img_size (int, int): (x, y)
        dst_img_size (int, int): (x, y)

    Returns:
        (int, int): (x, y)
    """
    ratio_x = dst_img_size[0] / src_img_size[0]
    ratio_y = dst_img_size[1] / src_img_size[1]
    if ratio_x < ratio_y:
        size = (dst_img_size[0], int(src_img_size[1] * ratio_x))
    else:
        size = (int(src_img_size[0] * ratio_y), dst_img_size[1])

    return size