# HG changeset patch
# User robcast
# Date 1298989071 -3600
# Node ID c07c21ac78f9029227946f0612e1af174eb2462d
# Parent  8ee72433bb8f4627b4082d057cd60c5ff6a8c95b
color invert operation. doesn't work with all image types yet...

diff -r 8ee72433bb8f -r c07c21ac78f9 servlet/src/digilib/image/DocuImage.java
--- a/servlet/src/digilib/image/DocuImage.java	Tue Mar 01 10:14:29 2011 +0100
+++ b/servlet/src/digilib/image/DocuImage.java	Tue Mar 01 15:17:51 2011 +0100
@@ -207,7 +207,7 @@
 	 * 
 	 *
 	 */
-	public enum ColorOp {GRAYSCALE};
+	public enum ColorOp {GRAYSCALE, INVERT};
 
 	/** Changes the colors of the current image.
 	 * 
diff -r 8ee72433bb8f -r c07c21ac78f9 servlet/src/digilib/image/ImageLoaderDocuImage.java
--- a/servlet/src/digilib/image/ImageLoaderDocuImage.java	Tue Mar 01 10:14:29 2011 +0100
+++ b/servlet/src/digilib/image/ImageLoaderDocuImage.java	Tue Mar 01 15:17:51 2011 +0100
@@ -27,9 +27,12 @@
 import java.awt.geom.Rectangle2D;
 import java.awt.image.AffineTransformOp;
 import java.awt.image.BufferedImage;
+import java.awt.image.ByteLookupTable;
 import java.awt.image.ColorConvertOp;
 import java.awt.image.ConvolveOp;
 import java.awt.image.Kernel;
+import java.awt.image.LookupOp;
+import java.awt.image.LookupTable;
 import java.awt.image.RescaleOp;
 import java.io.IOException;
 import java.io.OutputStream;
@@ -62,6 +65,7 @@
 	/** interpolation type */
 	protected RenderingHints renderHint;
 
+	/** convolution kernels for blur() */
 	protected static Kernel[] convolutionKernels = {
 	        null,
 	        new Kernel(1, 1, new float[] {1f}),
@@ -69,6 +73,23 @@
             new Kernel(3, 3, new float[] {1f/9f, 1f/9f, 1f/9f, 1f/9f, 1f/9f, 1f/9f, 1f/9f, 1f/9f, 1f/9f})
 	};
 
+	/** lookup table for inverting images (byte) */
+	protected static LookupTable invertByteTable;
+	
+	static {
+		byte[] invertByte = new byte[256];
+		byte[] orderedByte = new byte[256];
+		for (int i = 0; i < 256; ++i) {
+			invertByte[i] = (byte) (256 - i);
+			orderedByte[i] = (byte) i;
+		}
+		// works for JPEG in q2
+		invertByteTable = new ByteLookupTable(0, new byte[][] {
+				invertByte, invertByte, orderedByte, invertByte});
+		// should work...
+		/* invertByteTable = new ByteLookupTable(0, invertByte); */
+	}
+	
 	/** the size of the current image */
     protected ImageSize imageSize;
 	
@@ -482,10 +503,18 @@
 	public void colorOp(ColorOp op) throws ImageOpException {
 		if (op == ColorOp.GRAYSCALE) {
 			// convert image to grayscale
+			logger.debug("Color op: grayscaling");
 			ColorConvertOp colop = new ColorConvertOp(
 					ColorSpace.getInstance(ColorSpace.CS_GRAY), null);
 			img = colop.filter(img, null);
+		} else if (op == ColorOp.INVERT) {
+			// invert colors i.e. invert every channel
+			logger.debug("Color op: inverting");
+			// TODO: is this enough for all image types?
+			LookupOp colop = new LookupOp(invertByteTable, renderHint);
+			img = colop.filter(img, null);
 		}
+
 	}
 
 	public void rotate(double angle) throws ImageOpException {
diff -r 8ee72433bb8f -r c07c21ac78f9 servlet/src/digilib/servlet/Scaler.java
--- a/servlet/src/digilib/servlet/Scaler.java	Tue Mar 01 10:14:29 2011 +0100
+++ b/servlet/src/digilib/servlet/Scaler.java	Tue Mar 01 15:17:51 2011 +0100
@@ -31,7 +31,7 @@
     private static final long serialVersionUID = 5289386646192471549L;
 
     /** digilib servlet version (for all components) */
-    public static final String version = "1.9.1a13";
+    public static final String version = "1.9.1a14";
 
     /** servlet error codes */
     public static enum Error {UNKNOWN, AUTH, FILE, IMAGE};