filter_volume.c: prevent serializing previous_gain and reset previous_gain on seeking.

git-svn-id: https://mlt.svn.sourceforge.net/svnroot/mlt/trunk/mlt@1222 d19143bc-622f-0410-bfdd-b5b2a6649095

diff --git a/src/modules/normalize/filter_volume.c b/src/modules/normalize/filter_volume.c
index e745363..3bc747c 100644 (file)
--- a/src/modules/normalize/filter_volume.c
+++ b/src/modules/normalize/filter_volume.c
@@ -228,18 +228,22 @@ static int filter_get_audio( mlt_frame frame, int16_t **buffer, mlt_audio_format
                gain = max_gain;
 
        // Initialise filter's previous gain value to prevent an inadvertant jump from 0
-       if ( mlt_properties_get( filter_props, "previous_gain" ) == NULL )
-               mlt_properties_set_double( filter_props, "previous_gain", gain );
+       mlt_position last_position = mlt_properties_get_position( filter_props, "_last_position" );
+       mlt_position current_position = mlt_frame_get_position( frame );
+       if ( mlt_properties_get( filter_props, "_previous_gain" ) == NULL
+            || current_position != last_position + 1 )
+               mlt_properties_set_double( filter_props, "_previous_gain", gain );
 
        // Start the gain out at the previous
-       double previous_gain = mlt_properties_get_double( filter_props, "previous_gain" );
+       double previous_gain = mlt_properties_get_double( filter_props, "_previous_gain" );
 
        // Determine ramp increment
        double gain_step = ( gain - previous_gain ) / *samples;
 //     fprintf( stderr, "filter_volume: previous gain %f current gain %f step %f\n", previous_gain, gain, gain_step );
 
        // Save the current gain for the next iteration
-       mlt_properties_set_double( filter_props, "previous_gain", gain );
+       mlt_properties_set_double( filter_props, "_previous_gain", gain );
+       mlt_properties_set_position( filter_props, "_last_position", current_position );
 
        // Ramp from the previous gain to the current
        gain = previous_gain;
@@ -307,7 +311,7 @@ static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
                                        
                                // If there is an end adjust gain to the range
                                if ( mlt_properties_get( filter_props, "end" ) != NULL )
-                               {       
+                               {
                                        // Determine the time position of this frame in the transition duration
                                        mlt_position in = mlt_filter_get_in( this );
                                        mlt_position out = mlt_filter_get_out( this );