下載
wget https://github.com/tesseract-ocr/tesseract/archive/4.1.0.tar.gz
wget http://www.leptonica.org/source/leptonica-1.74.4.tar.gz
安裝依賴：yum install autoconf automake libtool libjpeg-devel libpng-devel libtiff-devel zlib-devel
安裝leptonica
tar -xzvf leptonica-1.74.4.tar.gz
cd leptonica-1.74.4.tar.gz
./configure --profix=/usr/local/leptonica
make
sudo make install
很多其他教程到這一步就直接開始安裝 tesseract，實際上如果你照着教程走的話，再 configure 的時候就會報錯：找不到 leptonica。所以我們要先配置一下 leptonica 的環境變量。
打開 /etc/profile
vim /etc/profile
添加以下字段
PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/leptonica/lib/pkgconfig
export PKG_CONFIG_PATH
CPLUS_INCLUDE_PATH=$CPLUS_INCLUDE_PATH:/usr/local/leptonica/include/leptonica
export CPLUS_INCLUDE_PATH
C_INCLUDE_PATH=$C_INCLUDE_PATH:/usr/local/leptonica/include/leptonica
export C_INCLUDE_PATH
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/leptonica/lib
export LD_LIBRARY_PATH
LIBRARY_PATH=$LIBRARY_PATH:/usr/local/leptonica/lib
export LIBRARY_PATH
LIBLEPT_HEADERSDIR=/usr/local/leptonica/include/leptonica
export LIBLEPT_HEADERSDIR
應用配置
source /etc/profile
OK，現在我們就可以開始安裝 tesseract。
安裝 tesseract
tar -xzvf 4.1.0.tar.gz
cd tesseract-4.1.0
./configure --profix=/usr/local/tesseract
make
sudo make install
接下來配置 tesseract 環境變量
打開 /etc/profile
vim /etc/profile
追加以下字段
PATH=$PATH:/usr/local/tesseract/bin
export PATH
應用配置
source /etc/profile
測試一下：
tesseract -v
輸出：
tesseract 4.1.0
leptonica-1.74.4
libjpeg 6b (libjpeg-turbo 1.2.90) : libpng 1.5.13 : libtiff 4.0.3 : zlib 1.2.7
Found AVX2
Found AVX
Found SSE
OK，到這里，我們就安裝成功了，你的安裝成功了嗎？有任何問題評論告訴我吧！