Consider parsing and drawing COCO box & seg labels

Consider adjust UI, ref: https://www.cnblogs.com/hhh5460/p/5170744.html

I followed the installation instructions exactly and everything was successfully installed. However, when I run python imageset-viewer.py I get the error in the title

Consider this: the whole image annotations is labeled by Person A, and checked by Person B. A didn't give B all the class names appeared in XML and B don't know it neither. But B just would like to check if labeles are OK.

Consider allowing not specifing class names mapping dict and automatic save class names when first meet each of them.

您好，

我使用win10端运行您的脚本，想读取我挂载的服务器硬盘中的图片，能显示图片名，但是无法显示图片。
Exception in Tkinter callback
Traceback (most recent call last):
File "C:\Users\AppData\Local\Programs\Python\Python36\lib\tkinter_init_.py", line 1705, in call
return self.func(*args)
File "imageset-viewer.py", line 353, in callback
self.tkim = self.get_tkim(im_pth)
File "imageset-viewer.py", line 379, in get_tkim
im_ht, im_wt, im_dt = im.shape
AttributeError: 'NoneType' object has no attribute 'shape'

请问您有解决办法吗？
谢谢

比如KeyError: 'sports ball', KeyError: 'tie', KeyError: 'zebra', KeyError: 'airplane'等