Some const correctness.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/lib/video_source.h b/src/lib/video_source.h
index e4a8ab058..748cb6fe9 100644
--- a/src/lib/video_source.h
+++ b/src/lib/video_source.h
@@ -45,7 +45,7 @@ public:
 	 *  Second parameter is true if the image is the same as the last one that was emitted.
 	 *  Third parameter is either 0 or a subtitle that should be on this frame.
 	 */
-	boost::signals2::signal<void (boost::shared_ptr<Image>, bool, boost::shared_ptr<Subtitle>)> Video;
+	boost::signals2::signal<void (boost::shared_ptr<const Image>, bool, boost::shared_ptr<Subtitle>)> Video;
 
 	void connect_video (boost::shared_ptr<VideoSink>);
 };
@@ -63,7 +63,7 @@ public:
 	 *  Third parameter is either 0 or a subtitle that should be on this frame.
 	 *  Fourth parameter is the source timestamp of this frame.
 	 */
-	boost::signals2::signal<void (boost::shared_ptr<Image>, bool, boost::shared_ptr<Subtitle>, double)> Video;
+	boost::signals2::signal<void (boost::shared_ptr<const Image>, bool, boost::shared_ptr<Subtitle>, double)> Video;
 
 	void connect_video (boost::shared_ptr<VideoSink>);
 	void connect_video (boost::shared_ptr<TimedVideoSink>);