TypeError：'NoneType'对象不是可迭代的-但似乎仍在列表中迭代？

问题描述

我对编码还很陌生，因此感谢您的帮助，如果很明显，我们对此表示歉意。

full_image_list = glob.glob(WORKING_DIR+'/data/JPEGImages/*.jpg')
fnames,classes = [],[]

for jpg_fname in full_image_list:
    fs,data = return_yolo_data(jpg_fname,ann_dir=WORKING_DIR+'/data/Annotations/')
    for f,d in zip(fs,data):
        fnames.append(f)

上面的代码给出以下错误：

> ---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
~/.virtualenvs/dl4cv/lib/python3.8/site-packages/numpy/lib/npyio.py in genfromtxt(fname,dtype,comments,delimiter,skip_header,skip_footer,converters,missing_values,filling_values,usecols,names,excludelist,deletechars,replace_space,autostrip,case_sensitive,defaultfmt,unpack,usemask,loose,invalid_raise,max_rows,encoding)
   1753             fid_ctx = contextlib_nullcontext(fid)
-> 1754         fhd = iter(fid)
   1755     except TypeError:

TypeError: 'NoneType' object is not iterable

During handling of the above exception,another exception occurred:

TypeError                                 Traceback (most recent call last)
<ipython-input-187-80766db0462f> in <module>
      2 
      3 for jpg_fname in full_image_list:
----> 4     fs,ann_dir=WORKING_DIR+'/data/Annotations/')
      5     for f,data):
      6         fnames.append(f)

<ipython-input-159-ecbad441c355> in return_yolo_data(jpg_fname,ann_dir)
     19     base_fname = jpg_fname.split('/')[-1] # no path
     20     txt_fname = get_yolo_file(base_fname,dir_=ann_dir)
---> 21     data = np.genfromtxt(txt_fname,names='class,x,y,w,h')
     22     # don't fail if there is only one labeled object in an image
     23     data = np.atleast_1d(data)

~/.virtualenvs/dl4cv/lib/python3.8/site-packages/numpy/lib/npyio.py in genfromtxt(fname,encoding)
   1754         fhd = iter(fid)
   1755     except TypeError:
-> 1756         raise TypeError(
   1757             "fname must be a string,filehandle,list of strings,"
   1758             "or generator. Got %s instead." % type(fname))

TypeError: fname must be a string,or generator. Got <class 'NoneType'> instead.

如果我使用此代码：

full_image_list = glob.glob(WORKING_DIR+'/data/JPEGImages/*.jpg')
fnames,data):
        print(f)

然后迭代显示每个文件的名称，每个文件都显示在单独的行中，并且没有逗号/语法，然后再显示相同的错误。

这是get_yolo_file函数和其他要求的代码。

def get_yolo_file(fname,dir_=WORKING_DIR+'/data/Annotations/'):
    '''
    takes image filename and returns annotation filename
    e.g. data/JPEGImages/IMG_XXX.jpg
         data/Annotations/IMG_XXX.txt
    '''
    txt_file = fname.replace('.jpg','.txt')
    full_path = '/'.join([dir_,txt_file])
    if os.path.isfile(full_path):
        return full_path
    else:
        print('ERROR')
        return None

def return_yolo_data(jpg_fname,ann_dir=WORKING_DIR+'/data/Annotations/'):
    '''
    Reads annotation file,returns name and data
    '''
    base_fname = jpg_fname.split('/')[-1] # no path
    txt_fname = get_yolo_file(base_fname,dir_=ann_dir)
    data = np.genfromtxt(txt_fname,h')
    # don't fail if there is only one labeled object in an image
    data = np.atleast_1d(data)
    # keep file name associated with each label
    fname_arr = [base_fname]*data.shape[0]
    return fname_arr,data

def str_class(val):
    '''
    Return string label for index. 
    YOLO is zero indexed.
    '''
    if val == 0:
        return 'one'
    elif val == 1:
        return 'two'
    elif val == 2:
        return 'three'
    elif val == 3:
        return 'four'
    elif val == 4:
        return 'five'
    elif val == 5:
        return 'six'

def create_image_dict(image_list,ann_dir=WORKING_DIR+'/data/Annotations/'):
    '''
    For input list of images,return a dictionary with label information.
    dictionary keys: image file,class (string),h,w 
    '''
    # empty lists for dictionary
    fnames,[]
    x,w = [],[],[]
    for jpg_fname in image_list:
        fs,ann_dir=ann_dir)
        for f,data):
            fnames.append(f)
            classes.append(str_class(d['class']))
            x.append(d['x'])
            y.append(d['y'])
            h.append(d['h'])
            w.append(d['w'])
    out_dict = {'filename':fnames,'class':classes,'x':x,'y':y,'h':h,'w':w}
    return out_dict

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

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iteration python