def get_start_timestamp_mapping(file_path):
    """Get mapping of video name id to star timestamp."""
    mapping = {}
    with open(file_path) as f_in:
        for line in f_in.readlines():
            if line.strip() == '':
                continue
            video_name, time_txt = line.strip().split(',')
            video_name_prefix = \
                '_'.join(video_name.split('_')[0:2])
            mapping[video_name_prefix.lower()] = time_txt
    return mapping