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When remapping time in the Graph Editor, use the values represented in the Time Remap graph to determine and control which frame of the movie plays at which point in time. Each Time Remap keyframe has a time value associated with it that corresponds to a specific frame in the layer; this value is represented vertically on the Time Remap value graph. When you enable time remapping for a layer, After Effects adds a Time Remap keyframe at the start and end points of the layer. These initial Time Remap keyframes have vertical time values equal to their horizontal position on the timeline.
By setting additional Time Remap keyframes, you can create complex motion results. Each time you add a Time Remap keyframe, you create another point at which you can change the playback speed or direction. As you move the keyframe up or down in the value graph, you adjust which frame of the video is set to play at the current time.
After Effects then interpolates intermediate frames and plays the footage forward or backward from that point to the next Time Remap keyframe. In the value graph, reading from left to right, an upward angle indicates forward playback, while a downward angle indicates reverse playback. The amount of the upward or downward angle corresponds to the speed of playback.
B C D A Time-remapping graph A. No change B. Fast motion C. Freeze frame D. Backward motion
The original duration of the source footage may no longer be valid when remapping time, because parts of the layer no longer play at the original rate. If necessary, set a new duration for the layer before you remap time.
As with other layer properties, you can view the values of the Time Remap graph as either a value graph or a speed graph.
If you remap time and the resulting frame rate is significantly different from the original, the quality of motion within the layer may suffer. Apply frame blending to improve slow- or fast-motion effects.
Note: Use the information shown in the Info panel to guide you as you work with time-remapping. The ratio given in the units of seconds/sec indicates the current speed of playback—the number of seconds of the original layer being played for each second after time-remapping.
See also “About animation, keyframes, and expressions” on page 183 “Work with the Graph Editor” on page 184 Time-remap a layer You can time-remap all or part of a layer. For example, you can time-remap a frame at the beginning or end of the layer, creating a freeze-frame result, or you can time-remap frames in the middle of the layer, creating a slow-motion result that only lasts for a few seconds.
See also “About animation, keyframes, and expressions” on page 183 “Work with the Graph Editor” on page 184 Freeze the first frame without changing the speed 1 In a Composition or Timeline panel, select the layer that you want to remap.
2 Choose Layer Time Enable Time Remapping.
This adds two Time Remap keyframes by default, one at the beginning of the layer and one at the end.
3 Move the current-time indicator to where you want the movie to begin.
4 Click the Time Remap property name to select the start and end keyframes.
5 Drag the first keyframe to the current-time indicator, which moves the start and end keyframes. (If you are working in the Graph Editor, drag the bounding box—not the keyframe or a handle—so that both keyframes move.)
6 Press Ctrl+C (Windows) or Command+C (Mac OS) to copy the keyframe.
7 Press Ctrl+V (Windows) or Command+V (Mac OS) to paste the keyframe at the current time. You should not have moved the current-time indicator since step 3.
8 (Optional) To extend the layer so that its duration is increased to accommodate the time added by the freezeframe operation, press the K key twice to move the current-time indicator to the last Time Remap keyframe, and press Alt+] (Windows) or Option+] (Mac OS).
The portion of the layer between the first and second keyframes plays at an unaltered rate (the same as for the nontime-remapped layer), as does the portion of the layer between the third and fourth keyframes. The second and third keyframes are identical, so a single frozen frame plays during the time between those two keyframes.
Remap time using the Graph Editor To switch between Graph Editor mode and layer bar mode, press Shift+F3.
1 In a Composition or Timeline panel, select the layer you want to remap.
2 Choose Layer Time Enable Time Remapping.
3 In the Timeline panel, click the name of the Time Remap property to select it.
4 Move the current-time indicator to the time at which to add a keyframe, and click the keyframe button in the keyframe navigator to add a keyframe.
5 In the Graph Editor, drag the keyframe marker up or down, watching the Time Remap value as you drag. To snap to other keyframes, Shift-drag.
Dragging the keyframe down slows down the layer.
• To freeze the previous keyframe, drag the current keyframe marker to a value equal to the previous keyframe value so that the graph line is flat. Another method is to select the keyframe and choose Animation Toggle Hold Keyframe, and then add another keyframe where you want the motion to start again.
Before you move a time-remap keyframe, it’s a good idea to select all subsequent time-remap keyframes in the layer first. This will preserve the timing of the rest of the layer when you remap time for the current keyframe.
Remap time in a Layer panel 1 Open the Layer panel for the layer you want to remap.
2 Choose Layer Time Enable Time Remapping. A second time ruler appears in the Layer panel above the default time ruler and the navigator bar.
3 On the lower time ruler, move the current-time indicator to the first frame where you want the change to occur.
4 On the upper time ruler, the remap-time marker indicates the frame currently mapped to the time indicated on the lower time ruler. To display a different frame at the time indicated on the lower time ruler, move the remap-time marker accordingly.
Drag the remap-time marker to replace the frame at the current time marker.
5 Move the current-time indicator on the lower time ruler to the last frame where you want change to occur.
6 Move the remap-time marker on the upper time ruler to the frame you want to display at the time indicated on
the lower time ruler:
• To move the preceding portion of the layer forward, set the remap-time marker to a later time than the currenttime indicator.
• To move the preceding portion of the layer backward, set the remap-time marker to an earlier time than the current-time indicator.
• To freeze a frame, set the remap-time marker to the frame you want frozen. Then, move the current-time indicator (lower ruler) to the last point in time where the frame will appear frozen and move the remap-time marker again to the frame you want frozen.
See also “Preview video and audio” on page 120 Change the pitch of an audio layer 1 In a Composition or Timeline panel, select the layer you want to remap.
2 Choose Layer Time Enable Time Remapping.
3 Click the Graph Editor button in the Timeline panel to display the Graph Editor, if necessary.
4 Click the Choose Graph Type And Options button at the bottom of the Graph Editor and choose Edit Speed Graph.
5 Move the current-time indicator to the frame where you want change to begin, and then click the Add A Keyframe button.
6 On the speed graph below the keyframe, drag a marker, watching the Speed value as you drag.
• To lower the pitch, drag the speed graph marker down.
• To increase the pitch, drag the speed graph marker up.
Remove clicks from new In and Out points 1 If necessary, choose panel Audio.
2 In the Timeline panel, select the audio (or audio and video) layer to which you applied time-remapping.
3 Expand the layer outline to display the Audio property and then the Audio Levels property.
4 Move the current-time indicator to the new In point and choose Animation Add Audio Levels Keyframe.
5 In the Audio panel, change the decibel value to 0.0.
6 Press the Page Up key on your keyboard to move the current-time indicator to the previous frame.
7 In the Audio panel, change the decibel level to -96.0.
8 Move the current time to the new Out point and set the decibel level to 0.
9 Press the Page Down key to move the current-time indicator to the next frame.
10 In the Audio panel, change the decibel level to -96.0.
You can change the decibel Slider Minimum value in the Audio Options dialog box, which is available from the Audio panel menu.
The Quality setting you select also affects frame blending. When the layer is set to Best quality, frame blending results in smoother motion but may take longer to render than when set to Draft quality.
Note: When working with a frame-blended layer in Draft mode, After Effects will always use Frame Mix interpolation to increase rendering speed.
You can also enable frame blending for all compositions when you render a movie.
Use frame blending to enhance the quality of time-altered motion in a layer that contains live-action footage—video, for example. You can apply frame blending to a sequence of still images, but not to a single still image. If you are animating a layer—for example, moving a text layer across the screen—use motion blur.
1 Select the layer in the Timeline panel.
2 Do one of the following:
• Choose Layer Frame Blending Frame Mix.
• Choose Layer Frame Blending Pixel Motion.
A check mark by the appropriate Frame Blending command (Frame Mix or Pixel Motion) indicates that it is applied to the selected layer. Also, the Frame Blending switch appears in the Switches column for the layer in the Timeline panel. Remove frame blending either by clicking the Frame Blending switch or by choosing the appropriate Frame Blending command again.
Regardless of the state of the layer switches, if frame blending is off for the composition, it is off for all layers in the composition. You set frame blending for the composition by choosing Enable Frame Blending from the Timeline panel menu, or clicking the Enable Frame Blending button at the top of the Timeline panel.
See also “About animation, keyframes, and expressions” on page 183 “Layer image quality” on page 150 “Timewarp effect” on page 535
Use this tool to place Overlap pins, which indicate which parts of an image should appear Puppet Overlap tool in front of others when distortion causes parts of the image to overlap one another.
Use this tool to place Starch pins, which stiffen parts of the image so that they are distorted less.
Puppet Starch tool Puppet mesh created by placing Deform pins (left), and result of dragging a Deform pin When you place the first pin, the area within an outline is automatically divided into a mesh of triangles. An outline is only visible when the Puppet effect has been applied and a Puppet tool pointer is over the area that the outline defines. (See “How the Puppet effect creates outlines” on page 230.) Each part of the mesh is also associated with the pixels of the image, so the image’s pixels move with the mesh.
Note: To show the mesh, select Show in the Tools panel.
When you move one or more Deform pins, the mesh changes shape to accommodate this movement, while keeping the overall mesh as rigid as possible. The result is that a movement in one part of the image causes natural, life-like movement in other parts of the image.
For example, if you place Deform pins in a person’s feet and hands and then move one of the hands to make it wave, the motion in the attached arm will be large, but the motion in the waist will be small, just as in the real world.
If a single animated Deform pin is selected, its Position keyframes are visible in the Composition panel and Layer panel as a motion path. You can work with these motion paths as you work with other motion paths, including setting keyframes to rove across time. (See “Smooth motion with roving keyframes” on page 216.) You can have multiple meshes on one layer. This is useful for deforming several parts of an image individually—such as text characters—as well as for deforming multiple instances of the same part of an image, each with a different deformation.
The original, undistorted mesh is calculated at the current frame at the time at which you apply the effect. The mesh does not change to accommodate motion in a layer based on motion footage, nor does the mesh update if you replace a layer’s source footage item.
Note: Because the render order for continuously rasterized layers—such as shape layers and text layers—is different than the render order for raster layers, you should not animate the position or scale of a continuously rasterized layer with layer transformations if you are also animating the layer with the Puppet tools. You can precompose the shape layer and use the Puppet tools on the precomposition layer, or you can use the Puppet tools to transform the shapes within the layer.
(See “Render order and collapsing transformations” on page 115 and “Continuously rasterize a layer containing vector graphics” on page 151.) The motion created by the Puppet tools is sampled by motion blur if motion blur is enabled for the layer and the composition, though the number of samples used is half of the value specified by the Samples Per Frame value. (See “Use motion blur” on page 200.) AFTER EFFECTS CS3 228 User Guide You can use expressions to link the positions of Deform pins to motion tracking data, audio amplitude keyframes, or any other properties.
Aharon Rabinowitz provides a tutorial that shows a creative way to use the Puppet tools with a particle generator to simulate airflow over a car: www.adobe.com/go/learn_ae_aharonpuppetparticles.
See also“Creating and modifying motion paths” on page 197
Manually animate an image with the Puppet tools The stopwatch switch is automatically set for the Position property of a Deform pin as soon as the pin is created.