ubuntu linux 1604 编译安装tesseract-ocr 4.0

主要参考官方的编译，梳理一下整个流程

Linux

The build instructions for Linux also apply to other UNIX like operating systems.

Dependencies

A compiler for C and C++: GCC or Clang
GNU Autotools: autoconf, automake, libtool
autoconf-archive
pkg-config
Leptonica
libpng, libjpeg, libtiff

Ubuntu

If they are not already installed, you need the following libraries (Ubuntu 16.04/14.04):

一、安装依赖：

sudo apt-get install g++ autoconf automake libtool autoconf-archive pkg-config libpng12-dev libjpeg8-dev libtiff5-dev zlib1g-dev  libleptonica-dev -y

或者一条一条复制：

sudo apt-get install g++ # or clang++ (presumably)

sudo apt-get install autoconf automake libtool

sudo apt-get install autoconf-archive

sudo apt-get install pkg-config

sudo apt-get install libpng12-dev

sudo apt-get install libjpeg8-dev

sudo apt-get install libtiff5-dev

sudo apt-get install zlib1g-dev

if you plan to install the training tools, you also need the following libraries:

安装训练所依赖的库：

sudo apt-get install libicu-dev libpango1.0-dev  libcairo2-dev


或者：
sudo apt-get install libicu-dev

sudo apt-get install libpango1.0-dev

sudo apt-get install libcairo2-dev

Leptonica

You also need to install Leptonica. Ensure that the development headers for Leptonica are installed before compiling Tesseract.

Tesseract versions and the minimum version of Leptonica required:

二、安装leptonica，

因为tesseract依赖这个库，否则在configure的时候会提示

最新的tesseract 4.0 及3.05 需要从Leptonica 源代码编译

git clone https://github.com/DanBloomberg/leptonica.git

cd leptonica

./configure

make -j8 && make install

Tesseract	Leptonica	Ubuntu
4.00	1.74.2	Must build from source
3.05	1.74.0	Must build from source
3.04	1.71	Ubuntu 16.04
3.03	1.70	Ubuntu 14.04
3.02	1.69	Ubuntu 12.04
3.01	1.67

One option is to install the distro's Leptonica package:

sudo apt-get install libleptonica-dev

but if you are using an oldish version of Linux, the Leptonica version may be too old, so you will need to build from source.

The sources are at https://github.com/DanBloomberg/leptonica . The instructions for building are given in Leptonica README.

Note that if building Leptonica from source, you may need to ensure that /usr/local/lib is in your library path. This is a standard Linux bug, and the information at Stackoverflow is very helpful.

Installing Tesseract from Git

Please follow instructions in https://github.com/tesseract-ocr/tesseract/wiki/Compiling--GitInstallation

Install elsewhere / without root

Tesseract can be configured to install anywhere, which makes it possible to install it without root access.

To install it in $HOME/local:

./autogen.sh

./configure --prefix=$HOME/local/

make install

To install it in $HOME/local using Leptonica libraries also installed in $HOME/local:

./autogen.sh

LIBLEPT_HEADERSDIR=$HOME/local/include ./configure \

  --prefix=$HOME/local/ --with-extra-libraries=$HOME/local/lib

make install

Video representation of the Compiling process for Tesseract 4.0 and Leptonica 1.7.4 on Ubuntu 16.xx

Video Build from Source Leptonica 1.7.4
Video Build from Source Tesseract-OCR 4.0

Language Data

Download the data file(s) for the language(s) you interest in.
Move it to the tessdata directory (e.g. 'mv tessdata $TESSDATA_PREFIX' if defined TESSDATA_PREFIX)

You can also use:

export TESSDATA_PREFIX=/some/path/to/tessdata

to point to your tessdata directory (example: if your tessdata path is '/usr/local/share/tessdata' you have to use 'export TESSDATA_PREFIX='/usr/local/share/').