4.5 User Interface: Timeline (Composition Builder v.5.0)
Timecode: Shows the current position of the CTI in the Timeline as SMPTE timecode
Playback control: Use the controls to jump to the beginning of the composition, one frame backward, play the composition, one frame forward, and to the end of the composition. When playing back the composition, stop frames are ignored but can be “previewed” using the “Preview” function.
Scale slider: Move the slider to change the scaling of the Timeline.
Stopframe control: Use the “arrow” keys to move the CTI to the previous/next stop frame, or click on the stop frame to add or remove a stop frame.
Stopframe: Stop frames (RED triangles) pause the composition Playout temporarily. Stop frames are interpreted differently in just:play and just:live. In just:play, the “Hold”-duration of a Stop frame is proportional to the length of the duration, which is set in the inspector of just:play. In just:live, a trigger has to be received by the composition to continue. Otherwise, it will be held infinitely (which may be useful for a corner logo graphic, for example). Stop frames can also be added/removed/modified in the “Document” tab of the Inspector. Refer to chapter → Stopframes for detailed information.
Every composition which is used as “Infinite graphics” must contain ONE stop frame; otherwise the graphics will go off the air once the composition reaches its predefined composition end.
Timeline Ruler: This is the timeline ruler. The CTI is snapped to the timeline ruler, depending on your selected frame rate.
CTI: Current time indicator. Indicates the current position in the Timeline. Drag it to scrub through time.
Components List: The components list shows the name of every component in your composition. Components have a disclosure triangle and a checkbox on the left side. In this example, there are several components from which the “TNN Bug” is expanded, showing its attributes.
Component Duration: Each component has an in-point and an out-point (i.e. “Start” and “End”). The in and out-point define the life span of a component and can also be used to reduce the rendering overhead because once the out-point has been reached, the component is taken out of the rendering pipeline. To define the in/out-point, drag the start/end of the grey bar in the timeline or use the inspector to set the duration of a component.
Keyframe(s): Keyframes are represented by YELLOW (selected) or GREY (unselected) diamonds. Composition Builder interpolates between keyframes to create a smooth transition. Composition Builder always interpolates sinusoidal.
Add Keyframe Button: Pressing this button creates a new keyframe at the CTI position of the corresponding attribute. In addition, each change of the attribute will result in a new/changed keyframe.
Resolution: Displays the resolution and frame rate of the composition. The value inside the braces is the square pixel resolution.