首先可以通過 官網github 安裝，自己源碼編譯，不過需要安裝各種依賴，也容易出錯，這里使用官方包管理器 yum 簡化操作。

yum 本身自帶的版本是 版本 3 ，過于老舊，很多 API 接口都不試用

[root@iZbp115r5t4hzamv0snvm1Z cim]# tesseract -v
tesseract 3.04.00
 leptonica-1.72
  libgif 4.1.6(?) : libjpeg 6b (libjpeg-turbo 1.2.90) : libpng 1.5.13 : libtiff 4.0.3 : zlib 1.2.7 : libwebp 0.3.0

所以通過切換倉庫，安裝 4.1 版本，執行命令如下：

# yum-config-manager --add-repo https://download.opensuse.org/repositories/home:/Alexander_Pozdnyakov/CentOS_7/
# sudo rpm --import https://build.opensuse.org/projects/home:Alexander_Pozdnyakov/public_key
# yum update tesseract
# yum list tesseract
# yum install tesseract
# [yum install tesseract-langpack-deu] # 可選安裝

如果執行命令報以下錯誤：

-bash: yum-config-manager: command not found

請查看該文章：yum-config-manager 命令找不到的解決方法

具體操作流程;

[root@iZbp115r5t4hzamv0snvm1Z cim]# yum-config-manager --add-repo https://download.opensuse.org/repositories/home:/Alexander_Pozdnyakov/CentOS_7/
Loaded plugins: fastestmirror
adding repo from: https://download.opensuse.org/repositories/home:/Alexander_Pozdnyakov/CentOS_7/

[download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_]
name=added from: https://download.opensuse.org/repositories/home:/Alexander_Pozdnyakov/CentOS_7/
baseurl=https://download.opensuse.org/repositories/home:/Alexander_Pozdnyakov/CentOS_7/
enabled=1


[root@iZbp115r5t4hzamv0snvm1Z cim]# sudo rpm --import https://build.opensuse.org/projects/home:Alexander_Pozdnyakov/public_key
[root@iZbp115r5t4hzamv0snvm1Z cim]# yum update tesseract
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * webtatic: us-east.repo.webtatic.com
download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_    | 1.3 kB  00:00:00
download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_/pr |  15 kB  00:00:07
download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_                   171/171
Package(s) tesseract available, but not installed.
No packages marked for update
[root@iZbp115r5t4hzamv0snvm1Z cim]# yum list tesseract
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * webtatic: us-east.repo.webtatic.com
Available Packages
tesseract.x86_64 4.1.0+git4242-1.4 download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_
[root@iZbp115r5t4hzamv0snvm1Z cim]# yum install tesseract
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * webtatic: us-east.repo.webtatic.com
Resolving Dependencies
--> Running transaction check
---> Package tesseract.x86_64 0:4.1.0+git4242-1.4 will be installed
--> Processing Dependency: tesseract-langpack-osd >= 3.99 for package: tesseract-4.1.0+git4242-1.4.x86_64
--> Processing Dependency: tesseract-langpack-eng >= 3.99 for package: tesseract-4.1.0+git4242-1.4.x86_64
--> Processing Dependency: liblept.so.5()(64bit) for package: tesseract-4.1.0+git4242-1.4.x86_64
--> Running transaction check
---> Package leptonica.x86_64 0:1.72-2.el7 will be updated
---> Package leptonica.x86_64 0:1.76.0-2.5 will be an update
---> Package tesseract-langpack-eng.noarch 0:4.00~git30-5.5 will be installed
---> Package tesseract-langpack-osd.noarch 0:4.00~git30-5.5 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=================================================================================================
 Package   Arch   Version
                    Repository                                                              Size
=================================================================================================
Installing:
 tesseract x86_64 4.1.0+git4242-1.4
                    download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_ 1.3 M
Installing for dependencies:
 tesseract-langpack-eng
           noarch 4.00~git30-5.5
                    download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_ 1.6 M
 tesseract-langpack-osd
           noarch 4.00~git30-5.5
                    download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_ 3.4 M
Updating for dependencies:
 leptonica x86_64 1.76.0-2.5
                    download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_ 1.0 M

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

Total download size: 7.3 M
Is this ok [y/d/N]: y
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
(1/4): tesseract-4.1.0+git4242-1.4.x86_64.rpm                             | 1.3 MB  00:00:06
(2/4): leptonica-1.76.0-2.5.x86_64.rpm                                    | 1.0 MB  00:00:07
(3/4): tesseract-langpack-eng-4.00~git30-5.5.noarch.rpm                   | 1.6 MB  00:00:01
(4/4): tesseract-langpack-osd-4.00~git30-5.5.noarch.rpm                   | 3.4 MB  00:00:02
-------------------------------------------------------------------------------------------------
Total                                                            751 kB/s | 7.3 MB  00:00:09
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : tesseract-langpack-eng-4.00~git30-5.5.noarch                                  1/5
  Updating   : leptonica-1.76.0-2.5.x86_64                                                   2/5
  Installing : tesseract-4.1.0+git4242-1.4.x86_64                                            3/5
  Installing : tesseract-langpack-osd-4.00~git30-5.5.noarch                                  4/5
  Cleanup    : leptonica-1.72-2.el7.x86_64                                                   5/5
  Verifying  : tesseract-langpack-osd-4.00~git30-5.5.noarch                                  1/5
  Verifying  : leptonica-1.76.0-2.5.x86_64                                                   2/5
  Verifying  : tesseract-langpack-eng-4.00~git30-5.5.noarch                                  3/5
  Verifying  : tesseract-4.1.0+git4242-1.4.x86_64                                            4/5
  Verifying  : leptonica-1.72-2.el7.x86_64                                                   5/5

Installed:
  tesseract.x86_64 0:4.1.0+git4242-1.4

Dependency Installed:
  tesseract-langpack-eng.noarch 0:4.00~git30-5.5  tesseract-langpack-osd.noarch 0:4.00~git30-5.5

Dependency Updated:
  leptonica.x86_64 0:1.76.0-2.5

Complete!
[root@iZbp115r5t4hzamv0snvm1Z cim]# yum install tesseract-langpack-deu
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * webtatic: us-east.repo.webtatic.com
Resolving Dependencies
--> Running transaction check
---> Package tesseract-langpack-deu.noarch 0:4.00~git30-5.5 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=================================================================================================
 Package
       Arch   Version
                    Repository                                                              Size
=================================================================================================
Installing:
 tesseract-langpack-deu
       noarch 4.00~git30-5.5
                    download.opensuse.org_repositories_home_Alexander_Pozdnyakov_CentOS_7_ 763 k

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

Total download size: 763 k
Installed size: 1.5 M
Is this ok [y/d/N]: y
Downloading packages:
tesseract-langpack-deu-4.00~git30-5.5.noarch.rpm                          | 763 kB  00:00:05
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : tesseract-langpack-deu-4.00~git30-5.5.noarch                                  1/1
  Verifying  : tesseract-langpack-deu-4.00~git30-5.5.noarch                                  1/1

Installed:
  tesseract-langpack-deu.noarch 0:4.00~git30-5.5

Complete!
[root@iZbp115r5t4hzamv0snvm1Z cim]# tesseract -v
tesseract 4.1.1-rc2-20-g01fb
 leptonica-1.76.0
  libjpeg 6b (libjpeg-turbo 1.2.90) : libpng 1.5.13 : libtiff 4.0.3 : zlib 1.2.7 : libwebp 0.3.0
 Found AVX512BW
 Found AVX512F
 Found AVX2
 Found AVX
 Found FMA
 Found SSE