friendica-addons/tesseract/vendor/thiagoalessio/tesseract_ocr/README.md

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<img src="https://thiagoalessio.github.io/tesseract-ocr-for-php/images/logo.png" alt="Tesseract OCR for PHP" align="right" width="320px"/>
# Tesseract OCR for PHP
A wrapper to work with Tesseract OCR inside PHP.
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<br/>
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## Installation
Via [Composer][]:
$ composer require thiagoalessio/tesseract_ocr
:bangbang: **This library depends on [Tesseract OCR][], version _3.02_ or later.**
<br/>
### ![][windows_icon] Note for Windows users
There are [many ways][tesseract_installation_on_windows] to install
[Tesseract OCR][] on your system, but if you just want something quick to
get up and running, I recommend installing the [Capture2Text][] package with
[Chocolatey][].
choco install capture2text --version 3.9
:warning: Recent versions of [Capture2Text][] stopped shipping the `tesseract` binary.
<br/>
### ![][macos_icon] Note for macOS users
With [MacPorts][] you can install support for individual languages, like so:
$ sudo port install tesseract-<langcode>
But that is not possible with [Homebrew][]. It comes only with **English** support
by default, so if you intend to use it for other language, the quickest solution
is to install them all:
$ brew install tesseract tesseract-lang
<br/>
## Usage
### Basic usage
<img align="right" width="50%" title="The quick brown fox jumps over the lazy dog." src="./tests/EndToEnd/images/text.png"/>
```php
use thiagoalessio\TesseractOCR\TesseractOCR;
echo (new TesseractOCR('text.png'))
->run();
```
```
The quick brown fox
jumps over
the lazy dog.
```
<br/>
### Other languages
<img align="right" width="50%" title="Bülowstraße" src="./tests/EndToEnd/images/german.png"/>
```php
use thiagoalessio\TesseractOCR\TesseractOCR;
echo (new TesseractOCR('german.png'))
->lang('deu')
->run();
```
```
Bülowstraße
```
<br/>
### Multiple languages
<img align="right" width="50%" title="I eat すし y Pollo" src="./tests/EndToEnd/images/mixed-languages.png"/>
```php
use thiagoalessio\TesseractOCR\TesseractOCR;
echo (new TesseractOCR('mixed-languages.png'))
->lang('eng', 'jpn', 'spa')
->run();
```
```
I eat すし y Pollo
```
<br/>
### Inducing recognition
<img align="right" width="50%" title="8055" src="./tests/EndToEnd/images/8055.png"/>
```php
use thiagoalessio\TesseractOCR\TesseractOCR;
echo (new TesseractOCR('8055.png'))
->allowlist(range('A', 'Z'))
->run();
```
```
BOSS
```
<br/>
### Breaking CAPTCHAs
Yes, I know some of you might want to use this library for the *noble* purpose
of breaking CAPTCHAs, so please take a look at this comment:
<https://github.com/thiagoalessio/tesseract-ocr-for-php/issues/91#issuecomment-342290510>
## API
### run
Executes a `tesseract` command, optionally receiving an integer as `timeout`,
in case you experience stalled tesseract processes.
```php
$ocr = new TesseractOCR();
$ocr->run();
```
```php
$ocr = new TesseractOCR();
$timeout = 500;
$ocr->run($timeout);
```
### image
Define the path of an image to be recognized by `tesseract`.
```php
$ocr = new TesseractOCR();
$ocr->image('/path/to/image.png');
$ocr->run();
```
### imageData
Set the image to be recognized by `tesseract` from a string, with its size.
This can be useful when dealing with files that are already loaded in memory.
You can easily retrieve the image data and size of an image object :
```php
//Using Imagick
$data = $img->getImageBlob();
$size = $img->getImageLength();
//Using GD
ob_start();
// Note that you can use any format supported by tesseract
imagepng($img, null, 0);
$size = ob_get_length();
$data = ob_get_clean();
$ocr = new TesseractOCR();
$ocr->imageData($data, $size);
$ocr->run();
```
### executable
Define a custom location of the `tesseract` executable,
if by any reason it is not present in the `$PATH`.
```php
echo (new TesseractOCR('img.png'))
->executable('/path/to/tesseract')
->run();
```
### version
Returns the current version of `tesseract`.
```php
echo (new TesseractOCR())->version();
```
### availableLanguages
Returns a list of available languages/scripts.
```php
foreach((new TesseractOCR())->availableLanguages() as $lang) echo $lang;
```
__More info:__ <https://github.com/tesseract-ocr/tesseract/blob/master/doc/tesseract.1.asc#languages-and-scripts>
### tessdataDir
Specify a custom location for the tessdata directory.
```php
echo (new TesseractOCR('img.png'))
->tessdataDir('/path')
->run();
```
### userWords
Specify the location of user words file.
This is a plain text file containing a list of words that you want to be
considered as a normal dictionary words by `tesseract`.
Useful when dealing with contents that contain technical terminology, jargon,
etc.
```
$ cat /path/to/user-words.txt
foo
bar
```
```php
echo (new TesseractOCR('img.png'))
->userWords('/path/to/user-words.txt')
->run();
```
### userPatterns
Specify the location of user patterns file.
If the contents you are dealing with have known patterns, this option can help
a lot tesseract's recognition accuracy.
```
$ cat /path/to/user-patterns.txt'
1-\d\d\d-GOOG-441
www.\n\\\*.com
```
```php
echo (new TesseractOCR('img.png'))
->userPatterns('/path/to/user-patterns.txt')
->run();
```
### lang
Define one or more languages to be used during the recognition.
A complete list of available languages can be found at:
<https://github.com/tesseract-ocr/tesseract/blob/master/doc/tesseract.1.asc#languages>
__Tip from [@daijiale][]:__ Use the combination `->lang('chi_sim', 'chi_tra')`
for proper recognition of Chinese.
```php
echo (new TesseractOCR('img.png'))
->lang('lang1', 'lang2', 'lang3')
->run();
```
### psm
Specify the Page Segmentation Method, which instructs `tesseract` how to
interpret the given image.
__More info:__ <https://github.com/tesseract-ocr/tesseract/wiki/ImproveQuality#page-segmentation-method>
```php
echo (new TesseractOCR('img.png'))
->psm(6)
->run();
```
### oem
Specify the OCR Engine Mode. (see `tesseract --help-oem`)
```php
echo (new TesseractOCR('img.png'))
->oem(2)
->run();
```
### dpi
Specify the image DPI. It is useful if your image does not contain this information in its metadata.
```php
echo (new TesseractOCR('img.png'))
->dpi(300)
->run();
```
### allowlist
This is a shortcut for `->config('tessedit_char_whitelist', 'abcdef....')`.
```php
echo (new TesseractOCR('img.png'))
->allowlist(range('a', 'z'), range(0, 9), '-_@')
->run();
```
### configFile
Specify a config file to be used. It can either be the path to your own
config file or the name of one of the predefined config files:
<https://github.com/tesseract-ocr/tesseract/tree/master/tessdata/configs>
```php
echo (new TesseractOCR('img.png'))
->configFile('hocr')
->run();
```
### setOutputFile
Specify an Outputfile to be used. Be aware: If you set an outputfile then
the option `withoutTempFiles` is ignored.
Tempfiles are written (and deleted) even if `withoutTempFiles = true`.
In combination with `configFile` you are able to get the `hocr`, `tsv` or
`pdf` files.
```php
echo (new TesseractOCR('img.png'))
->configFile('pdf')
->setOutputFile('/PATH_TO_MY_OUTPUTFILE/searchable.pdf')
->run();
```
### digits
Shortcut for `->configFile('digits')`.
```php
echo (new TesseractOCR('img.png'))
->digits()
->run();
```
### hocr
Shortcut for `->configFile('hocr')`.
```php
echo (new TesseractOCR('img.png'))
->hocr()
->run();
```
### pdf
Shortcut for `->configFile('pdf')`.
```php
echo (new TesseractOCR('img.png'))
->pdf()
->run();
```
### quiet
Shortcut for `->configFile('quiet')`.
```php
echo (new TesseractOCR('img.png'))
->quiet()
->run();
```
### tsv
Shortcut for `->configFile('tsv')`.
```php
echo (new TesseractOCR('img.png'))
->tsv()
->run();
```
### txt
Shortcut for `->configFile('txt')`.
```php
echo (new TesseractOCR('img.png'))
->txt()
->run();
```
### tempDir
Define a custom directory to store temporary files generated by tesseract.
Make sure the directory actually exists and the user running `php` is allowed
to write in there.
```php
echo (new TesseractOCR('img.png'))
->tempDir('./my/custom/temp/dir')
->run();
```
### withoutTempFiles
Specify that `tesseract` should output the recognized text without writing to temporary files.
The data is gathered from the standard output of `tesseract` instead.
```php
echo (new TesseractOCR('img.png'))
->withoutTempFiles()
->run();
```
### Other options
Any configuration option offered by Tesseract can be used like that:
```php
echo (new TesseractOCR('img.png'))
->config('config_var', 'value')
->config('other_config_var', 'other value')
->run();
```
Or like that:
```php
echo (new TesseractOCR('img.png'))
->configVar('value')
->otherConfigVar('other value')
->run();
```
__More info:__ <https://github.com/tesseract-ocr/tesseract/wiki/ControlParams>
### Thread-limit
Sometimes, it may be useful to limit the number of threads that tesseract is
allowed to use (e.g. in [this case](https://github.com/tesseract-ocr/tesseract/issues/898)).
Set the maxmium number of threads as param for the `run` function:
```php
echo (new TesseractOCR('img.png'))
->threadLimit(1)
->run();
```
## How to contribute
You can contribute to this project by:
* Opening an [Issue][] if you found a bug or wish to propose a new feature;
* Placing a [Pull Request][] with code that fix a bug, missing/wrong documentation
or implement a new feature;
Just make sure you take a look at our [Code of Conduct][] and [Contributing][]
instructions.
## License
tesseract-ocr-for-php is released under the [MIT License][].
<h2></h2><p align="center"><sub>Made with <sub><a href="#"><img src="https://thiagoalessio.github.io/tesseract-ocr-for-php/images/heart.svg" alt="love" width="14px"/></a></sub> in Berlin</sub></p>
[ci_badge]: https://github.com/thiagoalessio/tesseract-ocr-for-php/workflows/CI/badge.svg?event=push&branch=main
[ci]: https://github.com/thiagoalessio/tesseract-ocr-for-php/actions?query=workflow%3ACI
[appveyor_badge]: https://ci.appveyor.com/api/projects/status/xwy5ls0798iwcim3/branch/main?svg=true
[appveyor]: https://ci.appveyor.com/project/thiagoalessio/tesseract-ocr-for-php/branch/main
[codacy_badge]: https://app.codacy.com/project/badge/Grade/a81aa10012874f23a57df5b492d835f2
[codacy]: https://www.codacy.com/gh/thiagoalessio/tesseract-ocr-for-php/dashboard
[test_coverage_badge]: https://codecov.io/gh/thiagoalessio/tesseract-ocr-for-php/branch/main/graph/badge.svg?token=Y0VnrqiSIf
[test_coverage]: https://codecov.io/gh/thiagoalessio/tesseract-ocr-for-php
[stable_version_badge]: https://img.shields.io/packagist/v/thiagoalessio/tesseract_ocr.svg
[packagist]: https://packagist.org/packages/thiagoalessio/tesseract_ocr
[total_downloads_badge]: https://img.shields.io/packagist/dt/thiagoalessio/tesseract_ocr.svg
[monthly_downloads_badge]: https://img.shields.io/packagist/dm/thiagoalessio/tesseract_ocr.svg
[Tesseract OCR]: https://github.com/tesseract-ocr/tesseract
[Composer]: http://getcomposer.org/
[windows_icon]: https://thiagoalessio.github.io/tesseract-ocr-for-php/images/windows-18.svg
[macos_icon]: https://thiagoalessio.github.io/tesseract-ocr-for-php/images/apple-18.svg
[tesseract_installation_on_windows]: https://github.com/tesseract-ocr/tesseract/wiki#windows
[Capture2Text]: https://chocolatey.org/packages/capture2text
[Chocolatey]: https://chocolatey.org
[MacPorts]: https://www.macports.org
[Homebrew]: https://brew.sh
[@daijiale]: https://github.com/daijiale
[HOCR]: https://github.com/tesseract-ocr/tesseract/wiki/Command-Line-Usage#hocr-output
[TSV]: https://github.com/tesseract-ocr/tesseract/wiki/Command-Line-Usage#tsv-output-currently-available-in-305-dev-in-master-branch-on-github
[Issue]: https://github.com/thiagoalessio/tesseract-ocr-for-php/issues
[Pull Request]: https://github.com/thiagoalessio/tesseract-ocr-for-php/pulls
[Code of Conduct]: https://github.com/thiagoalessio/tesseract-ocr-for-php/blob/main/.github/CODE_OF_CONDUCT.md
[Contributing]: https://github.com/thiagoalessio/tesseract-ocr-for-php/blob/main/.github/CONTRIBUTING.md
[MIT License]: https://github.com/thiagoalessio/tesseract-ocr-for-php/blob/main/MIT-LICENSE