https://github.com/Danlock/gogosseract

A reimplementation of https://github.com/otiai10/gosseract without CGo, running Tesseract compiled to WASM with Wazero
https://github.com/Danlock/gogosseract

Last synced: 1 day ago
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A reimplementation of https://github.com/otiai10/gosseract without CGo, running Tesseract compiled to WASM with Wazero

• Host: GitHub
• URL: https://github.com/Danlock/gogosseract
• Owner: Danlock
• License: apache-2.0
• Created: 2023-10-28T02:19:06.000Z (about 1 year ago)
• Default Branch: main
• Last Pushed: 2023-11-07T06:05:17.000Z (about 1 year ago)
• Last Synced: 2024-10-03T06:45:11.156Z (about 1 month ago)
• Language: Go
• Size: 25.2 MB
• Stars: 136
• Watchers: 1
• Forks: 3
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# gogosseract

![Coverage](https://img.shields.io/badge/Coverage-70.4%25-brightgreen)

[![Go Report Card](https://goreportcard.com/badge/github.com/danlock/gogosseract)](https://goreportcard.com/report/github.com/danlock/gogosseract)

[![Go Reference](https://pkg.go.dev/badge/github.com/danlock/gogosseract.svg)](https://pkg.go.dev/github.com/danlock/gogosseract)

A reimplementation of https://github.com/otiai10/gosseract without CGo, running Tesseract compiled to WASM with Emscripten via Wazero.

Tesseract is an Optical Character Recognition library written in C++.

The WASM is generated from my [personal](https://github.com/Danlock/tesseract-wasm) fork of robertknight's well written tesseract-wasm project.

Note that Tesseract is only compiled with support for the LSTM neural network OCR engine, and not for "classic" Tesseract.

# Training Data

Tesseract requires training data in order to accurately recognize text. The official source is [here](https://github.com/tesseract-ocr/tessdata_fast). Strategies for dealing with this include downloading it at runtime, or embedding the file within your Go binary using go:embed at compile time.

# Accuracy

Tesseract can work better if the input images are preprocessed. See this page for tips.

https://tesseract-ocr.github.io/tessdoc/ImproveQuality.html

# Examples

Using Tesseract to parse text from an image.

```go

    trainingDataFile, err := os.Open("eng.traineddata")

    handleErr(err)

    cfg := gogosseract.Config{

        Language: "eng",

        TrainingData: trainingDataFile,

    }

    // While Tesseract's logs are very useful for debugging, you have the option to silence or redirect it

    cfg.Stderr = io.Discard

    cfg.Stdout = io.Discard

    // Compile the Tesseract WASM and run it, loading in the TrainingData and setting any Config Variables provided

    tess, err := gogosseract.New(ctx, cfg)

    handleErr(err)

    imageFile, err := os.Open("image.png")

    handleErr(err)

    err = tess.LoadImage(ctx, imageFile, gogosseract.LoadImageOptions{})

    handleErr(err)

    text, err = tess.GetText(ctx, func(progress int32) { log.Printf("Tesseract parsing is %d%% complete.", progress) })

    handleErr(err)

    // Closing the Tesseract instance will clean up everything used by Tesseract and it's WASM module

    handleErr(tess.Close(ctx))

```

Using a Pool of Tesseract workers for thread safe concurrent image parsing.

```go

    cfg := gogosseract.Config{

        Language: "eng",

        TrainingData: trainingDataFile,

    }

    // Create 10 Tesseract instances that can process image requests concurrently.

    pool, err := gogosseract.NewPool(ctx, 10, gogosseract.PoolConfig{Config: cfg})

    handleErr(err)

    // ParseImage loads the image and waits until the Tesseract worker sends back your result.

    hocr, err := pool.ParseImage(ctx, img, gogosseract.ParseImageOptions{

        IsHOCR: true,

    })

    handleErr(err)

    // Always remember to Close the pool to release resources

    handleErr(pool.Close())

```