All plays all frames in sequence. The sound playback may be choppy as each frame is calculated before being displayed.
To play audio when you play back the scene or scrub the timeline, you must first enable audio in the preferences property editor. You should also set the frame rate for playback.
When you play audio in Softimage, it links to the file you’re using for sound, but it does not load the entire file in RAM. This allows you to use very long streams, such as a QuickTime movie, because the length of the file is not important. However, Softimage needs to be able to load the sound chunks fast enough from the file, so the files need to be on a fast disk. If the files are compressed in complicated ways, if they are unnecessarily stereo or high-bit depth, or if they have more than one track, Softimage cannot get the audio samples fast enough and some stuttering may occur.
When you load an audio source into the mixer and create an audio clip, the audio is enabled by default. There are different ways to enable or mute the audio, depending on how you’re working.
To enable/mute audio for playback
• You can enable or mute the audio in general by clicking the Play/Mute Audio button on the Playback panel. Audio is muted when the button appears highlighted.
• You can enable or mute a specific audio track in the mixer by clicking its Mute icon. This mutes all audio clips that are on the track.
• You can enable or mute the audio only while scrubbing in the timeline—see Scrubbing the Audio.
The frame rate determines how smoothly the audio plays back. You will probably want to play back the audio in real time for better sound. As well, you can set the realtime playback rate to whatever percentage you like.
To switch between all frames and realtime playback
• Click the All/RT button next to the current frame box on the Playback panel:
- All plays all frames in sequence. The sound playback may be choppy as each frame is calculated before being displayed.
- 
RT (Real Time) gives priority to playing the sound smoothly. If necessary, playback speed is maintained by skipping frames.
To set a rate preference for realtime playback
1. Do either of the following:
- Choose Playback > Playback/Audio Preferences from the playback panel at the bottom of the Softimage window.
or
- Choose File > Preferences from the main menu. In the Preferences window that opens, click the Interaction icon.
2. In the Interaction Preferences property editor, click the Playback and Audio tab.
3. Set the Realtime Playback > User Rate % to any positive value. 100% is full speed, while 50% is half speed, 200% is double speed, and so on.
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The User Rate % slider goes only to 200 but you can enter values higher than that. |
To select a predefined realtime playback rate
• In the Playback menu, you can quickly select predefined realtime playback speed: 75%, 50%, or 25%. These options are available only when realtime playback is active.
When you do this, the User Rate % value in the Interaction preferences property editor is updated to match what you have selected.
Scrubbing means to drag the playback cursor back and forth in timeline. This is something that you need to do frequently as you check the sound in a clip. There are different modes that you can set for scrubbing, as well as the scrubbing playback rate.
To set options for audio scrubbing
1. Choose File > Preferences from the main menu to open the Interaction Preferences property editor (see Playback and Audio) and click the Playback and Audio tab.
2. Set the options in the Scrubbing area:
• Play Audio When Scrubbing activates the audio playback when scrubbing.
If you deselect this option, the audio is muted when you’re scrubbing, but is active when you click the Play icon in the playback controls.
• Default Scrub Mode is the main method to use when scrubbing. You can select from:
- Direct Seek: Plays exactly where you scrub the playback cursor.
- Play User Rate: Plays at the speed you specify for the Scrubbing > User Rate percentage value (below).
- Play Realtime: Plays at realtime speed.
- Play Vari Speed: Plays according to the speed at which you scrub the playback cursor.
• Alternate Scrub Mode is a different scrubbing method you can use when you press the Shift key. For example, you may want to scrub over only one area with a specific rate of playback (Play User Rate), but you want to do the main scrubbing with a different setting (such as Play Realtime).
The options for this parameter are the same as for Default Scrub Mode.
• User Rate % is the playback speed when you select Play User Rate for the Default and/or Alternate Scrub Mode options. This works in the same way as the Realtime Playback > User Rate % option.
3. Drag the playback cursor in the timeline to scrub the audio using these settings.
Synchronizing the Audio with the Animation While Scrubbing
There are two options in the Scrubbing area of the Interactions Preferences property editor that help you to better synchronize your audio with the animation while you’re scrubbing: Play Frame Entered When Scrubbing and Play Audio at Display Refresh When Scrubbing.
• The Play Frame Entered When Scrubbing option changes the audio behavior when scrubbing the playback cursor forward in the timeline.
When this option is off (default), the audio is played after the cursor has passed over the frame when you’re scrubbing: it is not played at the beginning of the frame.
When you select this option, instead of playing the audio segment on the frame that the cursor has just passed over, Softimage instead plays the audio segment on the frame that the cursor enters. For example, if you are scrubbing from frame 1 to frame 2, Softimage plays the audio segment on frames 2 to 3 instead of the segment on frames 1 to 2.
• The Play Audio at Display Refresh When Scrubbing option toggles the audio behavior with respect to the viewport display synchronization when scrubbing. When this option is on, the audio is played only after the viewport display update calculations have finished.
You may want to select this option when the geometry in your scene is heavy. In these cases, it can take longer for the viewport to update, which can cause a gap between the audio and the visual update. This option helps synchronize your audio with animation under these conditions.
Looping the audio lets you play a portion of the audio repeatedly. There are different ways in which you can loop the audio, depending on how you’re working: you can use the Quick Loop mode, loop the audio on a clip, or set up loop markers in the timeline as you would for any animation.
To quickly loop a range of frames around the playback cursor
1. Open the Interaction preferences property editor (see Enabling and Muting Audio) and click the Playback and Audio tab.
2. In the Quick Loop area, select Enable Quick Loop Mode.
3. Set the number of Frames Before/After Cursor. This determines where and for how long you want the loop.
For example, you could set 1 for the Frames Before Cursor and 20 for the Frames After Cursor to loop the 20 frames of audio that occur after the position of the playback cursor in the timeline.
4. Move the playback cursor in the main timeline or the animation mixer timeline to where you want to loop the audio and hold down the mouse button.
As long as you hold down the mouse button, the audio is looped back around the playback cursor according to the frames you have set for the Quick Loop mode.
5. When you release the mouse button, the looping stops. You can then click anywhere else in the timeline to continue to quickly loop other parts of the audio or just scrub the timeline.
To loop an audio clip
• Right-click the audio clip and choose Set In/Out Loop. This plays back the audio in the whole clip.
To loop a range of frames
1. Click the Loop icon 
in the playback controls.
2. Drag the yellow loop markers in the main timeline or the animation mixer timeline to delineate an area for playing back the audio.
Make sure an L or R appears beside the pointer before moving the loop markers (to move left or right, respectively).
You can monitor the output of the audio, in decibels, using a special audio monitor. This lets you see any peaks (displayed in orange) in the audio source.
This monitor is convenient to use because it doesn’t take up much space on the screen, and you don’t need to have the animation mixer open to see the audio waveforms.
To open the audio output monitor
• Choose View > General > Audio Output Monitor from the main menu.
You can also drag the audio clip from the mixer or explorer into the animation editor to see the peaks there (see the next section, Viewing Audio Waveforms).
Autodesk Softimage v.7.5