1 files changed, 7 insertions, 2 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/data/images/ComputeColorHistogram.java b/src/de/lmu/ifi/dbs/elki/data/images/ComputeColorHistogram.java
index 2c82c5bd..a13a4086 100644
--- a/src/de/lmu/ifi/dbs/elki/data/images/ComputeColorHistogram.java
+++ b/src/de/lmu/ifi/dbs/elki/data/images/ComputeColorHistogram.java
@@ -4,7 +4,7 @@ package de.lmu.ifi.dbs.elki.data.images;
  This file is part of ELKI:
  Environment for Developing KDD-Applications Supported by Index-Structures
 
- Copyright (C) 2011
+ Copyright (C) 2012
  Ludwig-Maximilians-Universität München
  Lehr- und Forschungseinheit für Datenbanksysteme
  ELKI Development Team
@@ -39,9 +39,14 @@ public interface ComputeColorHistogram extends Parameterizable {
   /**
    * Compute a color histogram given a file name.
    * 
+   * The mask file (which may be null) is expected to use >50% transparent or
+   * black to mask pixels, Non-transparent white to keep pixels. Alpha values
+   * are not used.
+   * 
    * @param file File name
+   * @param mask Mask file (optional)
    * @return Color histogram
    * @throws IOException on file read errors.
    */
-  public double[] computeColorHistogram(File file) throws IOException;
+  public double[] computeColorHistogram(File file, File mask) throws IOException;
 }
 \ No newline at end of file