# tesseract-sys
Rust bindings for [Tesseract](https://github.com/tesseract-ocr/tesseract). Requires version `4.1.0` or newer.
## Building
This links to the C libraries [leptonica](https://github.com/danbloomberg/leptonica) and tesseract.
On Ubuntu and derivatives the additional dependencies can be installed by running:
```bash
sudo apt-get install libleptonica-dev libtesseract-dev clang
```
On Fedora 30 the additional dependencies can be installed by running:
```bash
sudo dnf install leptonica-devel tesseract-devel clang
```
On Termux 2019 (Android, Android on Chromebooks) the additional dependencies can be installed by running:
```bash
pkg install libclang leptonica-dev tesseract-dev
```
### Building on Windows
On Windows, this library uses Microsoft's [vcpkg](https://github.com/microsoft/vcpkg) to provide tesseract.
Please install [vcpkg](https://github.com/microsoft/vcpkg) and **set up user wide integration** or [vcpkg crate](https://crates.io/crates/vcpkg) won't be able to find a library.
To install tesseract
```cmd
REM from the vcpkg directory
REM 32 bit
.\vcpkg install tesseract:x86-windows
REM 64 bit
.\vcpkg install tesseract:x64-windows
```
vcpkg allows building either dynamically or statically linked application
if you prefer dynamic linking
```cmd
SET VCPKGRS_DYNAMIC=true
```
for statically linked libraries
```cmd
SET RUSTFLAGS=-Ctarget-feature=+crt-static
```
To run the tests please download the [English trained data](https://github.com/tesseract-ocr/tessdata/blob/master/eng.traineddata) to this directory and set
```cmd
SET TESSDATA_PREFIX=.
```
If you prefer to compile tesseract yourself (Because, for example, you could not get vcpkg to build using clang-cl.exe), you can set these environment variables: `TESSERACT_INCLUDE_PATHS`, `TESSERACT_LINK_PATHS` and `TESSERACT_LINK_LIBS`.
For example:
```
set TESSERACT_INCLUDE_PATHS=D:\tesseract\build\include
set TESSERACT_LINK_PATHS=D:\tesseract\build\lib
set TESSERACT_LINK_LIBS=tesseract41
```
