diff --git a/imageio/imageio-core/src/main/java/com/twelvemonkeys/imageio/stream/SubImageOutputStream.java b/imageio/imageio-core/src/main/java/com/twelvemonkeys/imageio/stream/SubImageOutputStream.java
index 372e5758..2a24eef4 100644
--- a/imageio/imageio-core/src/main/java/com/twelvemonkeys/imageio/stream/SubImageOutputStream.java
+++ b/imageio/imageio-core/src/main/java/com/twelvemonkeys/imageio/stream/SubImageOutputStream.java
@@ -5,7 +5,8 @@ import javax.imageio.stream.ImageOutputStreamImpl;
 import java.io.IOException;
 
 /**
- * SubImageOutputStream.
+ * ImageInputStream that writes through a delegate, but keeps local position and bit offset.
+ * Note: Flushing or closing this stream will *not* have an effect on the delegate.
  *
  * @author <a href="mailto:harald.kuhr@gmail.com">Harald Kuhr</a>
  * @author last modified by $Author: harald.kuhr$