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;
// 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 );