Merging VCube, Руководство пользователя

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MXFix™ (Batch Export, Re-Wrapping) : Frame Rate Management Page 112
Frame Rate Management
The VCube application can manage different frame rates for Media Files, Composition, and TimeCode. For Conver-
sion or Rendering Processes, VCube uses the current Composition frame rate.
Media File Frame Rate Differs From Composition Frame Rate
If the Media File's frame rate is lower than the Composition frame rate, some frames will be duplicated.
If the Media File frame rate is higher than the Composition's frame rate, some frames will be dropped.
The Video Engine will play back the Media File preserving its original duration.
Playback duration can be changed if required by changing the speed of the Clip in the Timeline with a Double-
click on the Clip. [
Ctrl + W ]
NTSC Frame Rates
Composition frame rates of the NTSC family are stretched in time (I.e. one second lasts 1001 mS). This requires that
Clips be pulled-down to 99.9 % to preserve their original duration. In this case the Clip in the timeline needs to be
manually pulled out (expanded) on its Layer(s) to reflect the new duration.
Composition Rate Differs From Incoming TimeCode
The Timeline displays the External and the current Composition frame rate in the right bottom corner of the Time-
line.
The Overlay Tab settings enable external or internal (Composition) to be selected for Burnt In TimeCode.
The Composition will remain in sync. A second lasts a second for both Composition and TimeCode.
Note: The video engine must produce enough frames to match the chosen video standard of
the video card.
E.g:
• Using a 25 fps frame rate for the Composition produces video drops out on an NTSC video output. The
Composition frame rate must be set to 29.97 fps and the Clips must be pulled-down and resized into the
Timeline (expanded time). While playing, a PAL frame will be duplicated every six NTSC frames to preserve
the overall duration.
• Using a 24 fps frame rate for Composition produces video drops out on a PAL video output. The Composi-
tion frame rate must be set to 25 fps. A frame will be duplicated every second to preserve the overall dura-
tion.
Note: If the graphic card output is used, the Composition frame rate need not match any SD
video standard. 24 fps can be used as the Composition frame rate.
Only HD video formats allow film frame rates for the Composition on HD video cards.