Tesseract-OCR安装简明教程

引言：  OCR领域大名鼎鼎的Tesseract，开源项目，可以直接将图片中的文字进行识别，转换成文本信息，本文将简介如何安装以及进行数据的训练操作。
1.  Tesseract-OCR
   目前最新的tesseract项目已经全部迁移到了github上，我们可以从中获取所有主要的信息。
   地址： https://github.com/tesseract-ocr/tesseract 2.  Tesseract-OCR安装
  windows下的安装非常简单，直接安装可执行程序即可。这里重点介绍centos下的安装。这里提示一下，当你选择安装各类语言之时，则需要一个稍微耗时的等待操作，比如下图中所示的信息：
  


  操作系统： centos 7， JDK 8
  step1:     yum search tesseract
[root@flybird ~]# yum search tesseract-ocr
Loaded plugins: langpacks
========================================================================================================== Matched: tesseract-ocr ===========================================================================================================
tesseract.x86_64 : Raw OCR Engine
tesseract-devel.x86_64 : Development files for tesseract
tesseract-langpack-afr.noarch : Afrikaans language data for tesseract
tesseract-langpack-amh.noarch : Amharic language data for tesseract
tesseract-langpack-ara.noarch : Arabic language data for tesseract
tesseract-langpack-asm.noarch : Assamese language data for tesseract
tesseract-langpack-aze.noarch : Azerbaijani language data for tesseract
tesseract-langpack-aze_cyrl.noarch : "Azerbaijani language data for tesseract
tesseract-langpack-bel.noarch : Belarusian language data for tesseract
tesseract-langpack-ben.noarch : Bengali language data for tesseract
tesseract-langpack-bod.noarch : "Tibetan language data for tesseract
tesseract-langpack-bos.noarch : Bosnian language data for tesseract
tesseract-langpack-bul.noarch : Bulgarian language data for tesseract
tesseract-langpack-cat.noarch : Catalan language data for tesseract
tesseract-langpack-ceb.noarch : Cebuano language data for tesseract
............
 step2:  yum install tesseract.x86_64

[root@flybird ~]# yum install tesseract.x86_64
Loaded plugins: langpacks
Resolving Dependencies
--> Running transaction check
---> Package tesseract.x86_64 0:3.04.00-3.el7 will be installed
--> Processing Dependency: liblept.so.4()(64bit) for package: tesseract-3.04.00-3.el7.x86_64
--> Processing Dependency: libicuuc.so.50()(64bit) for package: tesseract-3.04.00-3.el7.x86_64
--> Processing Dependency: libicui18n.so.50()(64bit) for package: tesseract-3.04.00-3.el7.x86_64
--> Running transaction check
---> Package leptonica.x86_64 0:1.72-2.el7 will be installed
---> Package libicu.x86_64 0:50.1.2-15.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=============================================================================================================================================================================================================================================
Package Arch Version Repository Size
=============================================================================================================================================================================================================================================
Installing:
tesseract x86_64 3.04.00-3.el7 epel 11 M
Installing for dependencies:
leptonica x86_64 1.72-2.el7 epel 928 k
libicu x86_64 50.1.2-15.el7 base 6.9 M

Transaction Summary
=============================================================================================================================================================================================================================================
Install 1 Package (+2 Dependent packages)

Total download size: 19 M
Installed size: 67 M
Is this ok [y/d/N]: y
Downloading packages:
(1/3): leptonica-1.72-2.el7.x86_64.rpm | 928 kB 00:00:00
(2/3): libicu-50.1.2-15.el7.x86_64.rpm | 6.9 MB 00:00:07
(3/3): tesseract-3.04.00-3.el7.x86_64.rpm | 11 MB 00:00:11
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Total 1.7 MB/s | 19 MB 00:00:11
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : leptonica-1.72-2.el7.x86_64 1/3
Installing : libicu-50.1.2-15.el7.x86_64 2/3
Installing : tesseract-3.04.00-3.el7.x86_64 3/3
Verifying : tesseract-3.04.00-3.el7.x86_64 1/3
Verifying : libicu-50.1.2-15.el7.x86_64 2/3
Verifying : leptonica-1.72-2.el7.x86_64 3/3

Installed:
tesseract.x86_64 0:3.04.00-3.el7

Dependency Installed:
leptonica.x86_64 0:1.72-2.el7 libicu.x86_64 0:50.1.2-15.el7

Complete! step 3: 安装devel 

[root@flybird ~]# yum install tesseract-devel.x86_64 tesseract-osd.x86_64
Loaded plugins: langpacks
Resolving Dependencies
--> Running transaction check
---> Package tesseract-devel.x86_64 0:3.04.00-3.el7 will be installed
--> Processing Dependency: pkgconfig(lept) for package: tesseract-devel-3.04.00-3.el7.x86_64
--> Running transaction check
---> Package leptonica-devel.x86_64 0:1.72-2.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=============================================================================================================================================================================================================================================
Package Arch Version Repository Size
=============================================================================================================================================================================================================================================
Installing:
tesseract-devel x86_64 3.04.00-3.el7 epel 80 k
Installing for dependencies:
leptonica-devel x86_64 1.72-2.el7 epel 108 k

Transaction Summary
=============================================================================================================================================================================================================================================
Install 1 Package (+1 Dependent package)

Total download size: 188 k
Installed size: 1.1 M
Is this ok [y/d/N]: y
Downloading packages:
(1/2): tesseract-devel-3.04.00-3.el7.x86_64.rpm | 80 kB 00:00:00
(2/2): leptonica-devel-1.72-2.el7.x86_64.rpm | 108 kB 00:00:00
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Total 738 kB/s | 188 kB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : leptonica-devel-1.72-2.el7.x86_64 1/2
Installing : tesseract-devel-3.04.00-3.el7.x86_64 2/2
Verifying : leptonica-devel-1.72-2.el7.x86_64 1/2
Verifying : tesseract-devel-3.04.00-3.el7.x86_64 2/2

Installed:
tesseract-devel.x86_64 0:3.04.00-3.el7

Dependency Installed:
leptonica-devel.x86_64 0:1.72-2.el7

Complete! step 4:  安装lang package tesseract-langpack-chi_sim.noarch， tesseract-langpack-chi_tra.noarch

[root@flybird ~]# yum install tesseract-langpack-chi_sim.noarch
Loaded plugins: langpacks
Resolving Dependencies
--> Running transaction check
---> Package tesseract-langpack-chi_sim.noarch 0:3.04.00-3.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=============================================================================================================================================================================================================================================
Package Arch Version Repository Size
=============================================================================================================================================================================================================================================
Installing:
tesseract-langpack-chi_sim noarch 3.04.00-3.el7 epel 15 M

Transaction Summary
=============================================================================================================================================================================================================================================
Install 1 Package

Total download size: 15 M
Installed size: 40 M
Is this ok [y/d/N]: y
Downloading packages:
tesseract-langpack-chi_sim-3.04.00-3.el7.noarch.rpm | 15 MB 00:00:15
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : tesseract-langpack-chi_sim-3.04.00-3.el7.noarch 1/1
Verifying : tesseract-langpack-chi_sim-3.04.00-3.el7.noarch 1/1

Installed:
tesseract-langpack-chi_sim.noarch 0:3.04.00-3.el7

Complete!3.  Tesseract-OCR的使用
 a.  识别图片中的文字信息 

   命令格式：

tesseract imagename outputbase [-l lang] [-psm pagesegmode] [configfile...]

    操作： tesseract ttest.png out -l lang-type
   这里我们选取了两种图片，中文和英文图片；然后我们来看看OCR的效果如何。
 b. 检查tesseract支持的语言
[root@flybird practice]# tesseract --list-langs
List of available languages (4):
eng
osd
chi_tra
chi_sim 基于上述的信息可知，支持四种类型，三种语言， osd是开发的脚本
 c.  进行基于中文的OCR
    原图信息：
      


     进行OCR操作，操作命令： tesseract chin-ocr.png chin-out -l chi_sim
     运行结果：
[root@flybird practice]# tesseract chin-ocr.png chin-out -l chi_sim
Tesseract Open Source OCR Engine v3.04.00 with Leptonica
[root@flybird practice]# cat chin-out.txt
11月17日痿言 ′ 文童发文透露租妻子马伊蜊合作的新剧 (剃刀边缘) 快要刮作完
成) 感慨良多′他自称 ″过街者冒″ 租 ″笨人″ ′直言自己虽然忍不任茌片场发脾气′
但 ″i人亘″ 二字是心安理才寻她受了′  大家可以看到，识别率还是有待提高的，很多的信息并未准确识别出来。这里注意背景中有水印信息，造成了一定干扰。
 d. 基于英文的OCR识别
    原图信息：
   


     进行OCR操作， tesseract english-ocr.png eng-ocr -l eng

      运行的结果信息：
[root@flybird practice]# tesseract english-ocr.png eng-ocr -l eng
Tesseract Open Source OCR Engine v3.04.00 with Leptonica
[root@flybird practice]# cat eng-ocr.txt
I have lived in China for a long time and we all like it very much. We do have it done.
It is very funny in a good lucky state.
   基于本次的OCR结果还是非常理想的，当然这里是基于干扰非常少的情况下进行的。
4. 总结
    这里只是简要介绍了其安装信息与过程，更多的信息还是需要大家自行到tesseract上去获取信息，并自行实践的。