Time code and time display unit
Graphic explanation
Many quantities in AE are either points in time or spans of time, including the current time, layer In and Out points, and durations of layers, footage items, and compositions.
By default, AE displays time in timecode: minutes, seconds, milliseconds, and frames. You can change to another time display system, such as the number of frames.
note：Changing the time display format does not alter the frame rate of your assets or output—it changes only how frames are numbered for display in AE.
1. Options for time-display units
Timecode Use source timecode or start at 00:00:00 to display time as timecode in the time ruler in the Timeline, Layers, and Footage panels. Select the Timecode option to use timecode instead of frames.
Time ruler The time ruler visually represents the time dimension of an item, layer, or footage item.
Frames Displays frame number instead of time.
Timecode Conversion The size of the overall zoom time ruler or the conversion time-display unit. The plus sign is to enlarge the time scale until the display unit of the time code is converted from time to frames; the minus sign is the opposite of the plus sign, which is to reduce the time scale until the display unit of the time code is converted from frames to time.
2. Current-time indicator (CTI)
