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Shared Effects and Shared Tracks

Two other effect types available in the Attach Effect dialog are Shared effects and Shared tracks. In the case of a shared effect, the following conditions must be true:

- There must be other effects in the timeline.
- The other effects must be of the same type as the track you are attaching an effect to. That is for audio tracks, effect must be audio and for video tracks, effect must be a video effect.
- The insertion point or selected region must start inside the other effects.

Before going into further detail about how to use Shared effects, an easier alternative method of application which is especially useful for Audio tracks is available. In this method, all you have to do is use the Audio pulldown and choose Attach effect , highlight the effect you would like and make sure the default of Attach single standalone and share others is checked on. It will automatically be a "Shared Effect" on all audio tracks (be sure to disarm any audio tracks that you do not want to have the effect shared on). This method also works for Video tracks using the Video pulldown choice of Attach effect.

In the case of a shared track, there must be another track on the timeline of the same type as the track you are applying an effect to. If you right clicked on a video track to attach an effect, there will not be anything in the shared tracks column if no other video track exists. The same applies equally to audio tracks in that another audio track must exist. Shared tracks are often used as layers for titles, curves and keyframes.

If shared effects or shared tracks are available, they appear in the shared effects and shared tracks columns when you used the Attach effect option (RMB on a track). When the green colored checkmark is clicked OK, anything highlighted in the column is attached under the current track.

Shared effects and shared tracks allow very unique things to be done. In the case of a shared effect, the shared effect is treated like a copy of the original effect, except that in the shared effect the GUI can not be brought up. All configuration of the shared effect is determined by the GUI of the original effect and only the GUI of the original effect can be brought up.

When a shared effect is played back, it is processed just like a normal effect except the configuration is copied from the original effect. Some effects detect when they are being shared. These effects determine what tracks are sharing them and either mix the two tracks together or use one track to stage some value.

When an original track has a shared track as one of its effects, the shared track itself is used as a realtime effect. This is more commonly known as bouncing tracks but CINELERRA-GG achieves the same operation by attaching shared tracks. The fade and any effects in the shared track are applied to the original track. Once the shared track has processed the data, the original track performs any effects which come below the shared track and then composites it on the output.

In order to prevent the shared track from mixing the same data as the original track on the output, enable the output mute toggle in the patchbay next to each track for which you do not want to mix on the output. If you are making a video and you do want the shared track to composite the original track's data on the output a second time, the video from the shared track would always appear under the video from the original track, regardless of whether it was on top of the original track. This is because shared tracks are composited in order of their attachment. Since it is part of the original track it has to be composited before the original track is.