use ColorConvertOp instead of Graphics2D #31

Seems to increase the conversion performance by a factor of around 40

pom.xml

@@ -4,7 +4,7 @@
   <parent>
     <groupId>org.mycore</groupId>
     <artifactId>mycore-parent</artifactId>
-    <version>48</version>
+    <version>51</version>
   </parent>
   <groupId>org.mycore.iview2</groupId>
   <artifactId>image-tiler</artifactId>

src/main/java/org/mycore/imagetiler/MCRImage.java

@@ -21,6 +21,7 @@
 import java.awt.Rectangle;
 import java.awt.RenderingHints;
 import java.awt.image.BufferedImage;
+import java.awt.image.ColorConvertOp;
 import java.awt.image.ColorModel;
 import java.awt.image.IndexColorModel;
 import java.io.BufferedOutputStream;
@@ -115,6 +116,8 @@ public class MCRImage {
 
     private static final double ZOOM_FACTOR = 0.5;
 
+    private static final ColorConvertOp COLOR_CONVERT_OP = new ColorConvertOp(null);
+
     /**
      * derivate ID (for output directory calculation).
      */
@@ -247,7 +250,7 @@ private static Path getTiledFileBaseDir(Path tileDir, String derivateID) {
         if (lastPart.length() > MIN_FILENAME_SUFFIX_LEN) {
             baseDir = baseDir.resolve(
                 lastPart.substring(lastPart.length() - DIRECTORY_PART_LEN * 2, lastPart.length() - DIRECTORY_PART_LEN));
-            baseDir = baseDir.resolve(lastPart.substring(lastPart.length() - DIRECTORY_PART_LEN, lastPart.length()));
+            baseDir = baseDir.resolve(lastPart.substring(lastPart.length() - DIRECTORY_PART_LEN));
         } else {
             baseDir = baseDir.resolve(lastPart);
         }
@@ -282,7 +285,7 @@ private static ImageReader createImageReader(final ImageInputStream imageInputSt
             return null;
         }
         final ImageReader reader = readers.next();
-        reader.setInput(imageInputStream, false);
+        reader.setInput(imageInputStream, false, true);
         return reader;
     }
 
@@ -336,12 +339,7 @@ private static BufferedImage convertIfNeeded(BufferedImage tile) {
         }
         final BufferedImage newTile = new BufferedImage(tile.getWidth(), tile.getHeight(),
             convertToGray ? BufferedImage.TYPE_BYTE_GRAY : BufferedImage.TYPE_INT_RGB);
-        Graphics2D graphics2d = newTile.createGraphics();
-        try {
-            graphics2d.drawImage(tile, 0, 0, tile.getWidth(), tile.getHeight(), null);
-        } finally {
-            graphics2d.dispose();
-        }
+        COLOR_CONVERT_OP.filter(tile, newTile);
         return newTile;
     }
 

src/test/java/org/mycore/imagetiler/MCRImageTest.java

@@ -90,6 +90,7 @@ public void setUp() {
         pics.put("extra small", "src/test/resources/5x5.jpg");
         pics.put("tiff 48 bit", "src/test/resources/tiff48.tif");
         pics.put("tiff 16 bit", "src/test/resources/tiff16.tif");
+        pics.put("tiff ICC", "src/test/resources/rgb-to-gbr.tif");
 
         tileDir = Paths.get("target/tileDir");
         System.setProperty("java.awt.headless", "true");