def getCenterROI(image_name,df):
    """
    get center ROI from image name and dataframe
    Parameters:
        -image_name: name of image that match with name in dataframe
        -df: dataframe that contain image name and ROI center coordinate
    Returns:
        -x,y: coordinate of ROI center
    """
    x = df.loc[image_name][0]
    y = df.loc[image_name][1]
    return x,y