安装所需依赖
在你的 build.gradle 文件中添加以下依赖：

groovy

dependencies {
    implementation "com.squareup.okhttp3:okhttp:4.9.3"
    implementation "org.bytedeco:javacv-platform:1.5.5"
    implementation "com.sun.jna:jna:5.9.0"
}
下载并保存验证码图片
使用 OkHttp 下载验证码图片并保存到本地：

kotlin

import okhttp3.OkHttpClient
import okhttp3.Request
import java.io.File

fun downloadCaptcha(url: String, savePath: String) {
    val client = OkHttpClient()
    val request = Request.Builder().url(url).build()
    
    client.newCall(request).execute().use { response ->
        if (!response.isSuccessful) throw IOException("Unexpected code $response")

        File(savePath).writeBytes(response.body!!.bytes())
        println("验证码图片已保存为 $savePath")
    }
}

fun main() {
    val captchaUrl = "https://captcha7.scrape.center/captcha.png"
    val savePath = "captcha.png"
    downloadCaptcha(captchaUrl, savePath)
}
图像处理和 OCR 识别
使用 OpenCV 进行图像处理，并使用 Tesseract 进行验证码识别：

kotlin

import org.bytedeco.javacpp.opencv_core.*
import org.bytedeco.javacv.OpenCVFrameConverter
import org.bytedeco.javacv.FrameGrabber
import org.bytedeco.javacv.Java2DFrameConverter
import org.bytedeco.javacv.TesseractOCR
import org.bytedeco.javacv.Frame

fun preprocessImage(inputPath: String, outputPath: String) {
    val image = cvLoadImage(inputPath)
    cvCvtColor(image, image, CV_BGR2GRAY) // 转为灰度图像
    cvThreshold(image, image, 128.0, 255.0, CV_THRESH_BINARY) // 二值化处理
    cvSaveImage(outputPath, image)
    println("处理后的验证码图片已保存为 $outputPath")
}

fun recognizeCaptcha(imagePath: String): String {
    val tess = TesseractOCR.create()
    tess.setPageSegMode(6) // 模式设置
    tess.setImage(imagePath)
    return tess.getUTF8Text().string
}

fun main() {
    val inputPath = "captcha.png"
    val processedPath = "captcha_processed.png"

    preprocessImage(inputPath, processedPath)
    val captchaText = recognizeCaptcha(processedPath)
    println("识别结果: $captchaText")
}
自动化登录
使用 OkHttp 发送登录请求，携带识别到的验证码进行自动化登录：

kotlin

fun login(username: String, password: String, captcha: String) {
    val client = OkHttpClient()
    val requestBody = """
        {
            "username": "$username",
            "password": "$password",
            "captcha": "$captcha"
        }
    """.trimIndent()

    val request = Request.Builder()
        .url("https://captcha7.scrape.center/login")
        .post(RequestBody.create(MediaType.parse("application/json"), requestBody))
        .build()

    client.newCall(request).execute().use { response ->
        if (response.isSuccessful) {
            println("登录成功")
        } else {
            println("登录失败: ${response.message}")
        }
    }更多内容联系1436423940
}

fun main() {
    val captchaText = recognizeCaptcha("captcha_processed.png")
    login("admin", "admin", captchaText)
}