Started work on hashing and added a sample image for testing. First new unit test is broken due to array indexing issues. Configured the pom further for testing configuration. Added a few properties to support different levels or precision depending on the hash.

.gitignore

@@ -31,3 +31,6 @@ version.info
 # Copied README.md and LICENSE files
 src/includes/README.md
 src/includes/LICENSE
+
+# Image Tools Log Files
+*.err

pom.xml

@@ -101,6 +101,24 @@
         </excludes>
       </resource>
     </resources>
+    <testResources>
+      <testResource>
+        <directory>src/test/resources</directory>
+        <filtering>true</filtering>
+        <includes>
+          <include>**/*.properties</include>
+          <include>**/*.info</include>
+        </includes>
+      </testResource>
+      <testResource>
+        <directory>src/test/resources</directory>
+        <filtering>false</filtering>
+        <excludes>
+          <exclude>**/*.properties</exclude>
+          <exclude>**/*.info</exclude>
+        </excludes>
+      </testResource>
+    </testResources>
     <pluginManagement>
       <plugins>	
         <plugin>

src/main/resources/default.properties

@@ -6,13 +6,17 @@ version=${project.version}
 #images must be 90% similar
 image.differenceThreshold=0.90
 #control generation of hashes for new images.
+image.hash.precision=64
 image.ahash.use=true
 image.ahash.weight=0.70
+image.ahash.precision=8
 image.dhash.use=true
 image.dhash.weight=0.85
+image.dhash.precision=8
 #set to false if hashing images is taking too long
 image.phash.use=true
 image.phash.weight=1.0
+image.phash.precision=16
 
 #Default Thumbnail Settings
 #Directory where to store thumbnails

src/main/scala/com/sothr/imagetools/hash/AHash.scala

@@ -0,0 +1,10 @@
+package com.sothr.imagetools.hash
+
+/**
+  * Created by dev on 1/22/14.
+  */
+object AHash extends PerceptualHasher {
+   def getHash(imageData: Array[Array[Int]]): Long = {
+     return 0L
+   }
+ }

src/main/scala/com/sothr/imagetools/hash/DHash.scala

@@ -0,0 +1,30 @@
+package com.sothr.imagetools.hash
+
+/**
+ * Created by dev on 1/22/14.
+ */
+object DHash extends PerceptualHasher {
+  def getHash(imageData: Array[Array[Int]]): Long = {
+    val width = imageData.length
+    val height = imageData(0).length
+    var hash = 0L
+    for (row <- 0 until width) {
+      //println(f"Row: $row%d")
+      var previousPixel = imageData(row)(0)
+      var previousLocation = (row, 0)
+
+      //process each column
+      for (col <- 0 until height) {
+        //println(f"Column: $col%d")
+        hash <<= 1
+        val pixel = imageData(row)(col)
+        //binary or the current bit based on whether the value
+        //of the current pixel is greater or equal to the previous pixel
+        if (pixel >= previousPixel) hash |= 1 else hash |= 0
+        previousPixel = pixel
+        previousLocation = (row, col)
+      }
+    }
+    hash
+  }
+}

src/main/scala/com/sothr/imagetools/hash/HashService.scala

@@ -3,6 +3,10 @@ package com.sothr.imagetools.hash
 import grizzled.slf4j.Logging
 import com.sothr.imagetools.dto.ImageHashDTO
 import com.sothr.imagetools.util.{PropertiesEnum, PropertiesService}
+import com.sothr.imagetools.ImageService
+import java.awt.image.BufferedImage
+import javax.imageio.ImageIO
+import java.io.File
 
 /**
  * A service that exposes the ability to construct perceptive hashes from an
@@ -20,16 +24,16 @@ object HashService extends Logging {
     var phash:Long = 0L
 
     //Get Image Data
-    var imageData:Array[Array[Int]] = null
+    val image = ImageIO.read(new File(imagePath))
 
     if (PropertiesService.get(PropertiesEnum.UseAhash.toString) == "true") {
-      ahash = getAhash(imageData)
+      ahash = getAhash(image)
     }
     if (PropertiesService.get(PropertiesEnum.UseAhash.toString) == "true") {
-      dhash = getDhash(imageData)
+      dhash = getDhash(image)
     }
     if (PropertiesService.get(PropertiesEnum.UseAhash.toString) == "true") {
-      phash = getPhash(imageData)
+      phash = getPhash(image)
     }
     
     val hashes = new ImageHashDTO(ahash, dhash, phash)
@@ -38,16 +42,28 @@ object HashService extends Logging {
     return hashes
   }
 
-  def getAhash(imageData:Array[Array[Int]]):Long = {
-    return 0L
+  def getAhash(image:BufferedImage):Long = {
+    debug("Generating an AHash")
+    val grayImage = ImageService.convertToGray(image)
+    val resizedImage = ImageService.resize(grayImage, PropertiesService.get(PropertiesEnum.AhashPrecision.toString).toInt, true)
+    val imageData = ImageService.getImageData(resizedImage)
+    AHash.getHash(imageData)
   }
 
-  def getDhash(imageData:Array[Array[Int]]):Long = {
-    return 0L
+  def getDhash(image:BufferedImage):Long = {
+    debug("Generating an DHash")
+    val grayImage = ImageService.convertToGray(image)
+    val resizedImage = ImageService.resize(grayImage, PropertiesService.get(PropertiesEnum.DhashPrecision.toString).toInt, true)
+    val imageData = ImageService.getImageData(resizedImage)
+    DHash.getHash(imageData)
   }
 
-  def getPhash(imageData:Array[Array[Int]]):Long = {
-    return 0L
+  def getPhash(image:BufferedImage):Long = {
+    debug("Generating an PHash")
+    val grayImage = ImageService.convertToGray(image)
+    val resizedImage = ImageService.resize(grayImage, PropertiesService.get(PropertiesEnum.PhashPrecision.toString).toInt, true)
+    val imageData = ImageService.getImageData(resizedImage)
+    PHash.getHash(imageData)
   }
 
 }

src/main/scala/com/sothr/imagetools/hash/PHash.scala

@@ -0,0 +1,10 @@
+package com.sothr.imagetools.hash
+
+/**
+  * Created by dev on 1/22/14.
+  */
+object PHash extends PerceptualHasher {
+   def getHash(imageData: Array[Array[Int]]): Long = {
+     return 0L
+   }
+ }

src/main/scala/com/sothr/imagetools/hash/PerceptualHasher.scala

@@ -0,0 +1,10 @@
+package com.sothr.imagetools.hash
+
+/**
+ * Created by dev on 1/22/14.
+ */
+trait PerceptualHasher {
+
+  def getHash(imageData:Array[Array[Int]]):Long
+
+}

src/main/scala/com/sothr/imagetools/image/ImageService.scala

@@ -1,14 +1,91 @@
 package com.sothr.imagetools
 
 import grizzled.slf4j.Logging
+import java.awt.image.{DataBufferByte, BufferedImage}
+import net.coobird.thumbnailator.Thumbnails
 
 object ImageService extends Logging {
   
   /**
    * Get the raw data for an image
    */
-  def getImageData(path:String):Array[Array[Int]] = {
-    return null
+  def getImageData(image:BufferedImage):Array[Array[Int]] = {
+    return convertTo2DWithoutUsingGetRGB(image)
+  }
+
+  /**
+   * Quickly convert an image to grayscale
+   *
+   * @param image
+   * @return
+   */
+  def convertToGray(image:BufferedImage):BufferedImage = {
+    val grayImage = new BufferedImage(image.getWidth, image.getHeight, BufferedImage.TYPE_BYTE_GRAY)
+    val g = image.getGraphics
+    g.drawImage(image,0,0,null)
+    g.dispose()
+    grayImage
+  }
+
+  def resize(image:BufferedImage, size:Int, forced:Boolean=false):BufferedImage = {
+    if (forced) {
+      Thumbnails.of(image).forceSize(size,size).asBufferedImage
+    } else {
+      Thumbnails.of(image).size(size,size).asBufferedImage
+    }
+  }
+
+  /**
+   * Convert a buffered image into a 2d pixel data array
+   *
+   * @param image
+   * @return
+   */
+  private def convertTo2DWithoutUsingGetRGB(image:BufferedImage):Array[Array[Int]] = {
+
+    val pixels = image.getRaster.getDataBuffer.asInstanceOf[DataBufferByte].getData
+    val width = image.getWidth
+    val height = image.getHeight
+    val hasAlphaChannel = image.getAlphaRaster != null
+
+    val result = Array.ofDim[Int](height,width)
+    if (hasAlphaChannel) {
+      val pixelLength = 4
+      var row = 0
+      var col = 0
+      for (pixel <- 0 until pixels.length by pixelLength) {
+        var argb:Int = 0
+        argb += (pixels(pixel) & 0xff) << 24 //alpha
+        argb += (pixels(pixel + 1) & 0xff) //blue
+        argb += (pixels(pixel + 2) & 0xff) << 8 //green
+        argb += (pixels(pixel + 3) & 0xff) << 16 //red
+        result(row)(col) = argb
+        col += 1
+        if (col == width) {
+          col = 0
+          row += 1
+        }
+      }
+    } else {
+      val pixelLength = 3
+      var row = 0
+      var col = 0
+      for (pixel <- 0 until pixels.length by pixelLength) {
+        var argb:Int = 0
+        argb += -16777216; // 255 alpha
+        argb += (pixels(pixel) & 0xff) //blue
+        argb += (pixels(pixel + 1) & 0xff) << 8 //green
+        argb += (pixels(pixel + 2) & 0xff) << 16 //red
+        result(row)(col) = argb
+        col += 1
+        if (col == width) {
+          col = 0
+          row += 1
+        }
+      }
+    }
+
+    result
   }
   
 }

src/main/scala/com/sothr/imagetools/util/PropertiesEnum.scala

@@ -5,12 +5,16 @@ object PropertiesEnum extends Enumeration {
   val Version = Value("version")
   //default image settings
   val ImageDifferenceThreshold = Value("image.differenceThreshold")
+  val HashPrecision = Value("image.hash.precision")
   val UseAhash = Value("image.ahash.use")
   val AhashWeight = Value("image.ahash.weight")
+  val AhashPrecision = Value("image.ahash.precision")
   val UseDhash = Value("image.dhash.use")
   val DhashWeight = Value("image.dhash.weight")
+  val DhashPrecision = Value("image.dhash.precision")
   val UsePhash = Value("image.phash.use")
   val PhashWeight = Value("image.phash.weight")
+  val PhashPrecision = Value("image.phash.precision")
   //Default Thumbnail Settings
   val ThumbnailDirectory = Value("thumbnail.directory")
   val ThumbnailSize = Value("thumbnail.size")

src/test/java/com/sothr/imagetools/AppTest.java

@@ -7,8 +7,7 @@ import junit.framework.TestSuite;
 /**
  * Unit test for simple App.
  */
-public class AppTest 
-    extends TestCase
+public class AppTest extends TestCase
 {
     /**
      * Create the test case

src/test/resources/default.properties

@@ -0,0 +1,25 @@
+#Default Properties File
+#Image Tools version: ${project.version}
+version=${project.version}
+
+#Default Image Settings
+#images must be 90% similar
+image.differenceThreshold=0.90
+#control generation of hashes for new images.
+image.hash.precision=64
+image.ahash.use=true
+image.ahash.weight=0.70
+image.ahash.precision=8
+image.dhash.use=true
+image.dhash.weight=0.85
+image.dhash.precision=8
+#set to false if hashing images is taking too long
+image.phash.use=true
+image.phash.weight=1.0
+image.phash.precision=16
+
+#Default Thumbnail Settings
+#Directory where to store thumbnails
+thumbnail.directory=./cache/thumbnails/
+#Size of the thumbnail to generate and store
+thumbnail.size=128

src/test/scala/com/sothr/imagetools/BaseTest.scala

@@ -1,5 +1,12 @@
 package com.sothr.imagetools
 
-import org.scalatest.{FunSuite,Matchers,OptionValues,Inside,Inspectors}
+import org.scalatest.{FunSuite,Matchers,OptionValues,Inside,Inspectors,BeforeAndAfter}
 
-abstract class BaseTest extends FunSuite with Matchers with OptionValues with Inside with Inspectors
+abstract class BaseTest extends FunSuite with Matchers with OptionValues with Inside with Inspectors with BeforeAndAfter {
+
+  before {
+    AppConfig.configLogging()
+    AppConfig.loadProperties()
+  }
+
+}

src/test/scala/com/sothr/imagetools/hash/HashServiceTest.scala

@@ -0,0 +1,19 @@
+package com.sothr.imagetools.hash
+
+import com.sothr.imagetools.BaseTest
+import javax.imageio.ImageIO
+import java.io.File
+
+/**
+ * Created by dev on 1/23/14.
+ */
+class HashServiceTest extends BaseTest {
+
+  test("Calculate DHash") {
+    val sample = new File("./target/sample/sample_01_large.jpg")
+    val image = ImageIO.read(sample)
+    val hash = HashService.getDhash(image)
+    assert(hash == 0L)
+  }
+
+}