rusty-tesseract

A Rust wrapper for Google Tesseract

Description

• Brings all relevant command-line tesseract functionality to Rust
• Based on the Python wrapper for tesseract (i.e. https://github.com/madmaze/pytesseract)
• Enables testing a pre-trained tesseract model and outputting the results in different formats such as strings, bounding boxes, dicts, or dataframes.

Dependencies

Tesseract: https://github.com/tesseract-ocr/tesseract

Usage

1. Read Image

Create an Image object by specifying a path or alternatively an image array in (height, width, channel) format (similar to Python's numpy array for opencv). Note: Leave the Array3 parameter as is if you don't intend to use it. ```rust let mut img = Image::new( String::from("img/string.png"), Array3::::zeros((100, 100, 3)) );

// alternatively instantiate directly:

let mut img = Image { path: String::from("img/string.png"), ndarray: Array3::::zeros((100, 100, 3)) // example: creates an 100x100 pixel image with 3 colour channels (RGB) }; ```

2. Set tesseract parameters

Set tesseract parameters using the Args struct. ```rust let default_args = Args::new();

// the default parameters are /* pub fn new() -> Args { Args { config: HashMap::new(), lang: "eng", out_filename: "out", dpi: 150, boxfile: false } } */

// fill your own argument struct if needed let mut myargs = Args { outfilename: "out", // name of outputfile lang: "eng", // model language (tesseract default = 'eng') config: HashMap::new(), // create empty hashmap to fill with command line parameters such as --psm or --oem (see tesseract --help-extra) dpi: 150, // specify DPI for input image boxfile: false // specify whether the output should be a bounding box or string output }; imagetostringargs.config.insert("psm", "6"); // define page segmentation mode 6 (i.e. "Assume a single uniform block of text") imagetostring_args.config.insert("oem", "3"); // define optical character recognition mode 3 (i.e. "Default, based on what is available") ```

3. Get the tesseract model output

Choose either string, bounding box or data output: ```rust // string output let output = rustytesseract::imagetostring(&img, myargs); println!("The String output is: {:?}", output.Output_STRING);

// define bounding box parameters let mut imagetoboxesargs = Args { outfilename: "fontname.font.exp0", lang: "eng", config: HashMap::new(), dpi: 150, boxfile: true }; imagetoboxesargs.config.insert("psm", "6"); imagetoboxes_args.config.insert("oem", "3");

// boxes printed in OUTPUTDICT or OUTPUTDATAFRAME format store the key as a string (i.e. the character) and // store the value as a list of strings (if the same character occurs more than once) let boxes = rustytesseract::imagetoboxes(&img, imagetoboxesargs); println!("The Boxfile output is: {:?}", boxes.Output_DATAFRAME);

// imagetodata prints out both the "imagetostring()" and "imagetoboxes()" information + a creates a TSV table with confidences let data = rustytesseract::imagetodata(&img, defaultargs); println!("The data output is: {:?}", data.Output_DICT); ```

Get tesseract version

rust let tesseract_version = rusty_tesseract::get_tesseract_version(); println!("The tesseract version is: {:?}", tesseract_version);

Contributing

1. Fork the repository
2. Create a new feature branch (git checkout -b my-feature-branch-name)
3. Commit your new changes (git commit -m 'commit message' <changed-file>)
4. Push changes to the branch (git push origin my-feature-branch-name)
5. Create a Pull Request