通过网络传输手写信息
老师正在黑板上写字，我们希望通过低带宽网络实时传递黑板上的所有信息。我们该怎么做呢？
在一次采访中，我遇到了这个问题。
A teacher is writing on a blackboard and we want to pass all the information on the blackboard over a low-bandwidth network in real-time. How do we do it?
In one interview, I faced this question.
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我有一种感觉，这个问题的措辞使得无法使用其他计算机。如果我必须猜测的话，面试官希望受访者意识到每秒发送 20 次整个电路板的快照会占用太多带宽。相反，也许他们会意识到一支粉笔一次只能在黑板上的一个部分上写字，而且相对来说只能写——你在擦掉之前写了一堆东西。因此，由于带宽较低，我们可能只想每秒发送几次粉笔的当前位置，而在接收端，我们只需在粉笔所在的位置继续绘制像素即可。这样我们每秒只发送 20 个 x,y 对，而不是 20 个完整的位图。
I have a feeling the question was worded such that no other computers could be used. If I had to guess, the interviewer wanted the interviewee to realize that sending a snapshot of the entire board 20 times a second would be too bandwidth intensive. Instead, maybe they could realize that a piece of chalk can only write on one section of a board at a time, and is relatively write only - you write a bunch of stuff before erasing. So with our low bandwidth, we might want to just send the current position of the chalk several times a second, and on our receiving end, we just keep drawing pixels wherever the chalk is. that way we are just sending 20 x,y pairs a second rather than 20 entire bitmaps.
最简单的方法不需要花哨的技术或软件，而且几乎不需要任何努力就可以完成，就是让一名学生将黑板上的内容逐字转录到他们的笔记本电脑上。文本编辑器可以是像网络终端一样简单的东西，它可以在键入信息时将信息发布到远程计算机。
这是相关的：
http://thedailywtf.com/Articles/The_Complicator_0x27_s_Gloves.aspx
The simplest way, that requires no fancy tech or software and can be done with virtually no effort, is just to have one of the students transcribe the contents of the blackboard verbatim to their laptop. The text editor could be something as simple as a networked terminal that posts the information to the remote computer as it is typed.
This is relevant:
http://thedailywtf.com/Articles/The_Complicator_0x27_s_Gloves.aspx
我认为这取决于他使用的黑板类型。有一些新的黑板允许您保存其内容并然后打印。
我个人认为，如果你有那种黑板，方法就是传输屏幕上绘制的点的一对 x,y 坐标。如果他/她仅使用一种颜色，则颜色信息可能不是必需的。
但我认为@Mehrdad Afshari 解决方案是最通用且负担得起的！
I think it depends of the type of blackboard he's using. There are some new blackboards that allow you to save its contents and print then.
Personally I think that on way to do it, if you have that sort of blackboard, is to transmit a pair of x,y coordinates of the points drawn on the screen. The colour information may not be necessary if he/she is using only one color.
But I think @Mehrdad Afshari solution is the most general and affordable!
使用数码相机？
说实话，如果必须以更精细、更精细和文本的方式提取信息，还可能需要运行一些奇特的实时 OCR 引擎。
Use a digital camera?
To be serious, there could also be some fancy real time OCR engine running if information has to be extracted in a finer, more granular and textual way.