how do I resolve IndexError: list index out of range?

Question

我正在尝试复制此存储库：https://github.com/sujiongming/UCF-101_video_classification。运行 2_extract_files.py 文件时出现以下错误。

Traceback (most recent call last):
  File "2_extract_files.py", line 99, in <module>
    main()
  File "2_extract_files.py", line 96, in main
    extract_files()
  File "2_extract_files.py", line 38, in extract_files
    video_parts = get_video_parts(video_path)
  File "2_extract_files.py", line 76, in get_video_parts
    filename = parts[3]
IndexError: list index out of range

代码如下：

def extract_files():
    data_file = []
    folders = ['./train/', './test/']

    for folder in folders:
        class_folders = glob.glob(folder + '*')

        for vid_class in class_folders:
            class_files = glob.glob(vid_class + '/*.avi')

            for video_path in class_files:
                video_parts = get_video_parts(video_path)

                train_or_test, classname, filename_no_ext, filename = video_parts
                if not check_already_extracted(video_parts):

                    src = train_or_test + '/' + classname + '/' + \
                        filename
                    dest = train_or_test + '/' + classname + '/' + \
                        filename_no_ext + '-%04d.jpg'
                    call(["ffmpeg", "-i", src, dest])

                nb_frames = get_nb_frames_for_video(video_parts)

                data_file.append([train_or_test, classname, filename_no_ext, nb_frames])

                print("Generated %d frames for %s" % (nb_frames, filename_no_ext))

    with open('data_file.csv', 'w') as fout:
        writer = csv.writer(fout)
        writer.writerows(data_file)

    print("Extracted and wrote %d video files." % (len(data_file)))

def get_nb_frames_for_video(video_parts):
    train_or_test, classname, filename_no_ext, _ = video_parts
    generated_files = glob.glob(train_or_test + '/' + classname + '/' +
                                filename_no_ext + '*.jpg')
    return len(generated_files)

def get_video_parts(video_path):
    parts = video_path.split('/')
    filename = parts[3]
    filename_no_ext = filename.split('.')[0]
    classname = parts[2]
    train_or_test = parts[1]

    return train_or_test, classname, filename_no_ext, filename

任何人都可以告诉我我做错了什么并指导我如何获得正确的列表索引。提前致谢。

Window 10
Python 3.7.6

Answer 1

建议只使用os.path.split(video_path)和os.path.splitext()并逐步完成，它更安全，也更便携：

def get_video_parts(video_path):
    head, filename = os.path.split(video_path)
    filename_no_ext, ext = os.path.splitext(filename)
    head, classname = os.path.split(head)
    head, train_or_test = os.path.split(head)

    return train_or_test, classname, filename_no_ext, filename

https://docs.python.org/3/library/os.path.html#os.path.split

我有点过时了 - 所以你可能想尝试 pathlib 对路径对象进行更高级的操作 - 在这种情况下，它可能是 path.stem() 到获取没有扩展名的最后一部分的名称，然后 path.parent() 上去。

https://docs.python.org/3/library/pathlib.html#module-pathlib

how do I resolve IndexError: list index out of range?

how do I resolve IndexError: list index out of range?

python

deep-learning

data-extraction

os.path