2.8 branch: Add up-to-date ffmpeg plugin. This commint merges the following revisions from trunk: 9910, 9912, 9933, 9948, 9960, 9965, 9968-9969, 9990, 10030, 10053, 10082, 10161, 10391-10392, 10408, 10414, 10422, 10538, 10809, 10851, 10892, 10925, 10961, 11165, and 11177.

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; }