Syncing Animation to Sound
Using the displayed waveform in the Timeline palette, you can begin to synchronize the keyframes to the waveform’s sound. It is accomplished by simply selecting and moving those keys that are associated with the various sounds and aligning them to the waveform that is displayed in the Timeline palette or dragging the audio bars in the Sequencer to align with the Timeline keys. If you’re trying to synchronize your animation to a vocal track, then you’ll want to look into the lip-syncing methods, which are covered in Chapter 20, “Using Lip-Sync.”
If you’re dealing with a complex animation scene with lots of moving points, then the audio track may be slowed down as the computer struggles to display the animation and the sound. This problem only exists when playing back the animation in the working area. When the project is exported, the computer takes all the time it needs to export all the frames in sync with the audio.
Tip
To reduce the drain on the computer while playing back an animation in the working area, This allows the system to skip some animation frames in order to speed the playback. You can also enable the Fast Buffer option in the Display Quality dialog box to speed playback.
To synchronize keys with a soundtrack, follow these steps:
Open the Pogo stick.anme file from the Chapter 19 folder on the CD. This file includes a simple character on a pogo stick. The stick has been animated bobbing up and down using point motion to compress the spring and layer translation to move the remainder of the layer.
Select the File, Import, Audio File menu command and in the File dialog box that opens, select the Boing.wav file from the Chapter 19 folder on the CD. This sound file has two boing sounds over a couple of seconds. Once added to the project, the sound file’s waveform is shown in the Timeline palette.
In the Timeline palette, select the keys at frame 30 that are near the first boing sound as seen in the waveform and move them to just before the sound to frame 28.
Select the keys at frame 36 and move them to frame 32 where the boing sound is the loudest on the waveform. Then repeat steps 3 and 4 for the keys at frames 54 and 60 where the second boing sound happens.
Click the Motion Graph button at the top of the Timeline palette. Set the Scale value to 0.5 and the Center to 0. Click all the channels to the left to disable them except for the Layer Translation channel, which you need to double-click to access edit mode.
Notice the keys near the area of the sound waveform where the sound is the loudest. The key should be on the top part of the undulation wave. Select the key at frame 32 and drag it upward to increase the amount of bounce for this frame. This high bounce coincides with the boing sound shown in the waveform. Repeat this key movement for the second boing sound at frame 60. The resulting curve graph in the Timeline palette is shown in Figure 19.7.
Click the Play button (Spacebar) to see the resulting motion and hear the synchronized sound. Figure 19.8 shows the pogo stick dude.
