速度控制

速度控制会扭曲片段的时间，使其播放得比正常时更快或更慢。一个小于1.0的 全局速度 会使片段播放得更快；大于1.0则会使其播放得更快。播放得更快意味着某些帧被跳过，并且片段会在结束帧之前用完所有帧。当片段用完了显示的帧，它将会保持重复最后一帧；动作将会看起来被冻结。为了避免这种情况，将下一个片段放置于原来的片段中你想让动作继续的位置。

选项

拉伸至导入片段的长度

基于输入片段的长度自动计算 速度参数 。因此如果你创建一个1/2原始尺寸的片段，序列将会以2倍速播放。

使用速度

基于 速度参数 计算缩放值。

Note

你将不得不相应地手动重新调整片段的长度。

  • 速度参数

    使用该值叠加序列的当前速度。因此，0.5的值会使序列的速度减半，而2的值则会使序列的速度加倍。

帧号

指定要重映射当前帧的一帧，例如，设置该值为50则显示第50帧。然后这可手动 关键帧 以重新创建动画。

  • 缩放到长度

    Maps the frame range on a 0-1 scale. For example, using this and a Frame Number of 0.5 will select the frame halfway through the sequence.

叠加速度

在所有其他计算之后应用叠加器。

示例

创建一个慢动作效果

Suppose you want to slow your strip down. You need to affect the speed of the video clip without affecting the overall frame rate. Select the clip and Add ‣ Effect ‣ Speed Control effect strip. Click to drop it and press N to get the Properties. Uncheck the Stretch to input strip length option in the Effect Strip section. Set the Speed factor to be the factor by which you want to adjust the speed. To cut the displayed speed by 50%, enter 0.5. Now, a 275-frame clip will play at half speed, and thus display only the first 137 frames.

If you want the remaining frames to show in slow motion after the first set is displayed, double the Length of the source strip (since effects strip bounds are controlled by their source strips). If you are using a speed factor other than 0.5 then use the formula:

new_length = real_length / speed_factor

That is it, set your render to animate (in this example) all 550 frames.

Keyframing the Speed Control

../../../../_images/sequencer_sequencer_strips_effects_speed-control_keyframing.png

Keyframing the Frame number.

To get even finer control over your clip timing, you can use curves! While it is possible to keyframe the Speed factor, usually you want to keyframe the Frame number directly.

Uncheck Stretch to input strip length and uncheck Use as speed. You now have a Frame number field which you can keyframe. If you want the strip to animate at all you will have to insert some keyframes, otherwise it will look like a still. In most cases you will want to use the Graph editor view to set the curve interpolation to Linear since the default Bézier will rarely be what you want.

Tip

If you choose to keyframe the Speed factor instead, remember to Refresh All or the changes will not take effect.

更改视频帧速率

你可使用速度控制在视频的每秒传输帧数(fps)内改变帧速率。如果你渲染视频为一个序列集，你可分别通过使用一个小于或大于1的全局速度值有效地增加或减少单个创建的图像的数量。例如，如果你以30fps来录制一个5分钟的视频，并且想转录到24fps的影片中，你将会进入一个30/24的全局速度，或者1.25(激活帧混合以使影片模糊)。Blender会产生 9000 / 1.25 = 7200 = 5 × 60 × 24 帧，而不是产生 5 × 60 × 30 = 9000 帧。在这种情况下，设置 起始 =1， 结束 =7200，设置输出格式到30fps的 jpeg ，并且从 0001.jpg 到 7200.jpg 的图像文件会渲染输出，但这些图像会涵盖全部的9000帧。7200.jpg 的图像文件与9000帧相同。当你回看24fps的影片blend文件中的图像时，该片段将会确切地持续5分钟。