void mltDeleteTransparency(int pos, int track, int id);
void mltResizeTransparency(int oldStart, int newStart, int newEnd, int track, int id);
void mltInsertTrack(int ix);
+ void mltDeleteTrack(int ix);
/** Change speed of a clip in playlist. To do this, we create a new "framebuffer" producer.
This new producer must have its "resource" param set to: video.mpg?0.6 where video.mpg is the path