12 Transport controls


Transport controls are just as useful in navigation as they are in playing back footage, hence they are described here in the navigation section. Each of the Viewer, Compositor, and Program windows has a transport panel.

The transport panel.

transport_panel.png


The transport panel is controlled by the keyboard as well as the graphical interface. For each of the operations it performs, the starting position is the position of the insertion point in the Program window and the slider in the Compositor window. The ending position is either the end or start of the timeline or the end or start of the selected region if there is one.

The orientation of the end or start depends on the direction of playback. If it is forward the end position is the end of the selected region. If it is backward the end position is the start of the selected region.

The insertion point moves to track playback. When playback stops, the insertion point stays where playback stopped. Thus, by playing back you change the position of the insertion point.

The keyboard interface is usually the fastest and has more speeds.
The transport keys are arranged in a sideways T on the number pad.


3 Play 0 Stop 6 Reverse
1 Frame Forward 2 Forward Slow + Reverse Fast
4 Frame back 5 Reverse Slow Enter Fast Forward


Hitting any key on the keyboard twice pauses it.

When using frame advance functions the behavior may seem odd. If you frame advance forward and then frame advance backward, the displayed frame does not change. This is because the playback position is not the frame but the time between two frames. The rendered frame is the area that the playback position crosses. When you increment the time between two frames by one and decrement it by one, you cross the same frame both times and so the same frame is displayed.

The transport behavior changes if you hold down <CTRL> when issuing any of the transport commands. This causes the starting point to be the In point if playing forward and the Out point if playing backward.
If playing forward, the Out point becomes the ending point and if playing backward, the In point becomes the ending point. If no In/Out points are specified, the behavior falls back to using the insertion point and track boundaries as the starting and ending points.

It is possible to use a hardware JogShuttle.
Refer to David Arendt’s message posted on the Cinelerra CV old mailing-list on the 2003-11-11 for more information.