From Tanguy Fautre,

Clean up of the FFmpeg plugin's class API/AudioStream API. 
Implementation of isImageTransparent().
Implementation of Image:g/setPixelAspectRatio()

include/osg/ImageStream

@@ -78,7 +78,8 @@ class OSG_EXPORT ImageStream : public Image
 
 
         virtual double getLength() const { return 0.0; }
-        
+        virtual double getFrameRate() const { return 0.0; } 
+
         virtual void setReferenceTime(double) {}
         virtual double getReferenceTime() const { return 0.0; }
                 
@@ -88,7 +89,6 @@ class OSG_EXPORT ImageStream : public Image
         virtual void setVolume(float) {}
         virtual float getVolume() const { return 0.0f; }
 
-
         typedef std::vector< osg::ref_ptr<osg::AudioStream> > AudioStreams;
         void setAudioStreams(const AudioStreams& asl) { _audioStreams = asl; }
         AudioStreams& getAudioStreams() { return _audioStreams; }