recaptcha

Golang captcha recognition library, by using Tesseract C++ and Opencv library.

Build

os version

$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 20.04.4 LTS
Release:	20.04
Codename:	focal

go version

$ go version
go version go1.20.4 linux/amd64

$ sudo apt update
$ sudo apt install -y libtesseract-dev libleptonica-dev
$ sudo wget https://github.com/hybridgroup/gocv/archive/refs/tags/v0.34.0.tar.gz
$ sudo tar -zxf v0.34.0.tar.gz && cd gocv-0.34.0 && make install
$ sudo rm -rf ${HOME}/v0.34.0.tar.gz ${HOME}/gocv-0.34.0

Docker

Runtime environment use docker

$ cd recaptcha
$ sudo docker-compose up

Example

golang client

package main

import (
	"fmt"
	"github.com/sechelper/recaptcha"
	"log"
	"os"
	"path/filepath"
)

func main() {
	cli := recaptcha.NewClient("http://127.0.0.1:60080/v1/captcha/image", recaptcha.Options{
		PageSegMode: 13,
		Languages:   []string{"eng"},
		Whitelist:   "1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ",
	})

	var captcha1381, _ = filepath.Abs("testdata/captcha/1381.png")
	file1381, err := os.Open(captcha1381)
	defer file1381.Close()
	if err != nil {
		panic(err)
	}

	cli.PushCaptcha(recaptcha.Captcha{Content: file1381, ID: file1381.Name()})

	var captcha1133, _ = filepath.Abs("testdata/captcha/1133.png")
	file1133, err := os.Open(captcha1133)
	defer file1133.Close()
	if err != nil {
		panic(err)
	}
	cli.PushCaptcha(recaptcha.Captcha{Content: file1133, ID: file1133.Name()})
	rec, err := cli.Image()

	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(rec)
}

curl

$ cd recaptcha
$ curl -X POST -H "Content-Type: multipart/form-data"   -F "captcha[]=@testdata/captcha/1424.png" -F "captcha[]=@testdata/captcha/1133.png" -F 'options={"psm":13,"languages":["eng"], "whitelist":"1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"}' http://127.0.0.1:60080/v1/captcha/image
$ curl -X POST -H "Content-Type: application/json" -d '{"psm":13,"languages":["eng"], "whitelist":"1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ","captcha":[{"id":"1653.png", "text":"iVBORw0KGgoAAAANSUhEUgAAACwAAAASCAMAAAAXKszuAAACZ1BMVEX19fXPPeCcPI3dXcHmPoh0JMAeiwlvj2aashQWjtBCXk+MymZH/Yz9c8wcG1ueBUMh3qIxTwEF4CDdJKokktFcrzhR2YsA8hngXfyU663k+xE8kaW3lxp9lazPzX5vYPiWAKzzj/pBxldMdIdhp06LKJ4AG5BdJcdg6h4QjNxvOnpMXM/FChjqUjITXo8aZ1ZtRHebBdAdez80cBrRYBOFyBUw4zDPRMsTou4nmRit6A7S/02H5R+YABiNEV7UmhHUAA71OxnJKFj7n5JZyOFXL5bbZcEXRm2hR2SD9+/7sWvGB7aWhwyizp5gAaiAudnFACQg9s8RsC4v/FO/Gh9zk3yqzC9H/FhLMGz16TILmgshVtqxalRqbuRZapREYeqMrKYOI7Yv7P8AA6/HkmrxbShEtPWh1Ngb2h/q/Xh5VYiWIZrzoyp2wV1uiWiC1ZPogjZs23QMjlr6JzGEzwbMXp+CusS/6dDctnExQXn60E+Tm9zL2rw14XghW2M+DR2mVggXBL0nGo5kiR4fDdbIe+bA2AWXvyM7/pxoGgGh/LInxL/m0lkn0aXT8dqyWvXi01rDugL0hhGLiYOUxixhBfaXVp9g1p+PbBz2fdwRdl5M/6ezDePilBxWqq4CpLTYLl1Ux14onVK7oVKPXBGNsoS22/rDddn1AyQJdIgvMbDCMU+8iR438wxQnDTk/H8lZwHi4bAuYoqXpAR+molfMEudajQW6OEAfcyVd4JEPvYQuUbyxuPIJiJ2OJ2DR8/Jg28E35202JIJnu+rc21LraMtFmYjQwl6Z0gbAnx3NJ1JlMWIwlMTpk6jAAAACXBIWXMAAA7EAAAOxAGVKw4bAAABFklEQVQokWNgAAEeBhiYzqAMonYxMBTBxYQZvBiwgWQgTkRwS7EqQoDdBOSRwEzswtHIHEZGKIMJCICUATMEqDKYMqxnAQIUtVDFNkwg9UAGMzOQKAcJgRUiqWaEKWZi2sZQxgBSrAZUbIRkHEL1cQZRiOJ5TAxyINoTZDIz2HR0tSCztaEmM/SCXQFRCVMNcXMhiLkA5sFjDGDfgXAOA8MyBoRqNJOXAwktBiZdqPlAsA9ZMUj1QbSgAyqrhSiGKIOQXWhGgxVvhaiDORqqFqRsMlrQwc2GqGXokYaFRj48UrYwIINZDGigFUymAXF7AEzsJLoiBobDmEKYoJ/BHUw3n4YL+YtgKhNEMNdA6cx1UMZCCAUArYEe3879S5oAAAAASUVORK5CYII="}]}' http://127.0.0.1:60080/v1/captcha/base64

Thanks

• https://github.com/otiai10/gosseract
• https://gocv.io/
• https://github.com/charlesw/tesseract