Add FilterCaptcha

FilterCaptcha generates a random string, creates an image of the string, and applies a series of filters to make the string hard to read.

src/main/scala/BlurCaptcha.scala

@@ -12,7 +12,7 @@ class BlurCaptcha extends CaptchaProvider {
     val blur = new GaussianBlurFilter(5)
     blur.apply(image)
     val s = scala.util.Random
-    val token = s.nextInt(1000).toString
+    val token = s.nextInt(10000).toString
     val challenge = new Challenge(token, image)
     val answer = "about"
     tokenAnswer += token -> answer

src/main/scala/FilterCaptcha.scala

@@ -0,0 +1,68 @@
+import com.sksamuel.scrimage._
+import com.sksamuel.scrimage.filter._
+import java.awt.image.BufferedImage
+import java.awt.{Graphics2D,Color,Font}
+
+class FilterCaptcha extends CaptchaProvider {
+  val tokenAnswer = scala.collection.mutable.Map[String, String]()
+  def getChallenge(): Challenge = {
+    val filterTypes = List(new FilterType1, new FilterType2)
+    val r = new scala.util.Random
+    val alphabet = "abcdefghijklmnopqrstuvwxyz"
+    val n = 8
+    val answer = Stream.continually(r.nextInt(alphabet.size)).map(alphabet).take(n).mkString
+    val token = scala.util.Random.nextInt(10000).toString
+    tokenAnswer += token -> answer
+    val canvas = new BufferedImage(225, 50, BufferedImage.TYPE_INT_RGB)
+    val g = canvas.createGraphics()
+    g.setColor(Color.WHITE)
+    g.fillRect(0, 0, canvas.getWidth, canvas.getHeight)
+    g.setColor(Color.BLACK)
+    g.setFont(new Font("Serif", Font.PLAIN, 30))
+    g.drawString(answer, 5, 30)
+    g.dispose()
+    var image = new Image(canvas, ImageMetadata.empty)
+    val s = scala.util.Random.nextInt(2)
+    image = filterTypes(s).applyFilter(image)
+    val challenge = new Challenge(token, image)
+    challenge
+  }
+  def checkAnswer(token: String, input: String): Boolean = {
+    if(tokenAnswer(token)==input)
+    {
+      true
+    }
+    else
+    {
+      false
+    }
+  }
+}
+
+trait FilterType {
+  def applyFilter(image: Image): Image
+}
+
+class FilterType1 extends FilterType {
+  override def applyFilter(image: Image): Image = {
+    val blur = new GaussianBlurFilter(2)
+    val smear = new SmearFilter(com.sksamuel.scrimage.filter.SmearType.Circles, 10, 10, 10, 0, 1)
+    val diffuse = new DiffuseFilter(2)
+    blur.apply(image)
+    diffuse.apply(image)
+    smear.apply(image)
+    image
+  }
+}
+
+class FilterType2 extends FilterType {
+  override def applyFilter(image: Image): Image = {
+    val smear = new SmearFilter(com.sksamuel.scrimage.filter.SmearType.Circles, 10, 10, 10, 0, 1)
+    val diffuse = new DiffuseFilter(1)
+    val ripple = new RippleFilter(com.sksamuel.scrimage.filter.RippleType.Noise, 1, 1, 0.005.toFloat, 0.005.toFloat)
+    diffuse.apply(image)
+    ripple.apply(image)
+    smear.apply(image)
+    image
+  }
+}

src/main/scala/Main.scala

@@ -2,7 +2,7 @@ import com.sksamuel.scrimage._
 import java.io._
 
 class CaptchaLibrary {
-  val captchas = List(new BlurCaptcha, new LabelCaptcha)
+  val captchas = List(new BlurCaptcha, new LabelCaptcha, new FilterCaptcha)
   var tokenCaptcha = scala.collection.mutable.Map[String, CaptchaProvider]()
   def init = {}
   def shutdown = {}
@@ -32,9 +32,6 @@ class Answer(val token: String, val input: String)
 object LibreCaptcha {
   def main(args: Array[String]) {
     val captcha = new CaptchaLibrary
-    var a = 0
-    for (a <- 1 to 3)
-    {
       val challenge = captcha.getChallenge()
       println(s"Token: ${challenge.token}")
       challenge.image.output(new File("Captcha.png"))
@@ -43,5 +40,4 @@ object LibreCaptcha {
       val result = captcha.checkAnswer(challenge.token, input)
       println(s"Result: $result")
   }
-  }
 }