Machine Learning - XVIII. Application Example Photo OCR应用实例-照片OCR(Week10)

http://blog.csdn.net/pipisorry/article/details/44999703

机器学习Machine Learning - Andrew NG courses学习笔记

Application Example Photo OCR应用实例照片

OCR(Optical Character Recognition)光学文字辨识

Problem Description and Pipeline问题描述和管道

three reasons to centered around an application called Photo OCR:first to show you an example of how a complex machine learning system can be put together.Second, once told the concepts of a machine learning a pipeline and how to allocate resources when you‘re trying to decide what to do next.Finally, the Photo OCR problem also tell you about a couple more interesting ideas for machine learning.One is how to apply machine learning to computer vision, and second is the idea of artificial data synthesis.

Photo OCR pipeline

Note:some photo OCR systems do more complex things,like spelling correction at the end.For example character segmentation and character classification system tells you that it sees word c 1 e a n i n g. Then,spelling correction system might tell you that this is probably the word ‘cleaning‘, and your character classification algorithm had just mistaken the l for a 1.

Note:

1. A system like this is called a machine learning pipeline.In particular, here‘s a picture showing the photo OCR pipeline.
2. pipelines are common, where you can have multiple modules,each of which may be machine learning component,or sometimes it may not be a machine learning component but to have a set of modules that act one after another on some piece of data in order to produce the output you want.

3. designing a machine learning system one of the most important decisions will often be what exactly is the pipeline that you want to put together.In other words, given the photo OCR problem, how do you break this problem down into a sequence of different modules.And each the performance of each of the modules in your pipeline.will often have a big impact on the final performance of your algorithm.


Sliding Windows滑窗

Getting Lots of Data and Artificial Data获取大量数据和人工数据

Ceiling Analysis：What Part of the Pipeline to Work on Next 上限分析-接下来用管道的什么部分工作

from:http://blog.csdn.net/pipisorry/article/details/44999703