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Performing Trims

Now that you know what each trim technique does, let’s explore how to trim in Media Composer.

To enter Trim mode:

  1. In the Timeline, place the position indicator near the transition you want to trim.
  2. Click the Record Track buttons for all tracks that you want to trim.
  3. Do one of the following:

In addition to selecting the appropriate tracks and clicking the Trim Mode button, you can enter Trim mode by lassoing the transition that you want to trim.

To lasso the transition:

  1. Position the pointer in the gray area above the top track in the Timeline.
  2. Click the mouse button, and drag a lasso around a transition (on one or more tracks). The position indicator snaps to the lassoed transition.
  3. After you enter Trim mode, if necessary, select or deselect the Record Track buttons to isolate the tracks you want to trim.

Trim Interface Changes

When you enter Trim mode, the interface changes. You are no longer looking at the Source and Record monitors; instead, you are looking at the A-side Trim monitor (which represents the last frame of the A-side clip) and the B-side Trim monitor (which represents the first frame of the B-side clip). The picture shown here depicts other such trim-related changes that occur.

Performing a Dual-Roller Trim

When you enter Trim mode, you automatically are set up for a dual-roller trim, indicated by the presence of trim rollers on each side of the transition point.

In addition, both trim boxes (between the A-side Trim monitor and B-side Trim monitor) are highlighted in pink.

And finally, when you hover your pointer over the transition, it turns into a dual-roller trim icon.

To perform a dual-roller trim using the Trim buttons:

  1. Before performing the trim, it’s often useful to play the transition several times to analyze exactly how it looks and what you think should be done to change it. To repeatedly play the currently selected transition, click the Play Loop button below the B-side monitor, or press 5 while in Trim mode. To stop looping the playback, click the Play Loop button again or press 5 or the space bar.
  2. After you’ve decided how you’d like to perform the trim, use the Trim buttons (below the A-side Trim monitor) to add frames to one side of the selected transition, and remove them from the other.

    The Trim buttons correspond to the M, comma, period, and backslash keys on the keyboard.

  3. To analyze the result of your trim, you can loop the playback by repeating step 1.

    You can also trim by dragging the trim rollers in the Timeline.

To trim by dragging the rollers:

  1. Click one or more trim rollers in the Timeline, and then drag them forward or back in the sequence. The pointer turns to a hand icon as you drag.

    If you are performing a single-roller trim, make sure that the Trim pointer is pointed in the direction you want to trim.

  2. Ctrl+drag (Windows) or Command+drag (Macintosh) to snap to an IN or OUT mark, the previous or next edit point, or an edit point on another track.

    As you trim, the trim boxes display the number of frames that have been trimmed from the outgoing and incoming sides of the transition.

Exiting Trim Mode

After you’ve performed your trim, you’ll want to exit Trim mode.

To exit Trim mode and return to Source/Record mode, do one of the following:

  • Click the Source/Record Mode button at the bottom of the Timeline palette or between the right and left Trim monitors.
  • Click anywhere in the timecode (TC1) track in the Timeline.
  • Click the Trim Mode button.
  • Click a Step Forward or Step Backward button below the Trim monitors.
  • Press a Step key (1, 2, 3, 4).
  • Press the Escape key.

Performing a Single-Roller Trim

Performing an A-side or B-side single-roller trim is very similar to performing a dual-roller trim, but you first have to choose which side you want to trim.

To perform a single-roller trim:

  1. Click the picture of the outgoing (A-side) or incoming (B-side) frame.

    The dual pink Trim mode rollers in the Timeline turn into a single yellow roller that moves to the side of the clip to be trimmed.

    The corresponding trim box (in the Trim window) is highlighted, and the other one is not highlighted.

    Additionally, the pointer becomes a yellow single-roller icon when you hover it over the transition point.

  2. To analyze the transition for trimming, you may want to loop the playback repeatedly through the transition. To do this, click the Play Loop button, or press the 5 key or space bar.
  3. Trim the transition earlier or later by clicking the Trim buttons.
  4. To analyze the result of your trim, you can loop the playback across the transition again by repeating step 2.

Trimming Using the Trim Smart Tools

In addition to entering Trim mode to perform trims, you can also trim using the Ripple Trim and Overwrite Trim buttons in the Smart Tool.

Trimming with the Smart Tool trim buttons is a very tactile way to interact with your footage; you can select trims in the Timeline without first entering Trim mode.

Ripple Trim

Ripple Trim performs the same type of trim that has been discussed already in this chapter. The term ripple simply means that both additive trims (trims in which you add frames to the A- or B-side of a clip) and reductive trims (trims in which you remove frames from the A- or B-side of a clip) shuffle all adjacent frames forward or backward as the trim is performed. (You can also perform dual-roller trims while using the Smart Tool trim buttons.)

To use Ripple Trim:

  1. In the Smart Tool, click the Ripple Trim button.
  2. Select a transition in the Timeline.
    • To perform an A-side single-roller trim, click to the left of the transition.
    • To perform a B-side single-roller trim, click to the right of the transition.
  3. Perform the trim by clicking the appropriate Trim button. (Loop the playback before and after the trim, as necessary.)

Overwrite Trim

Overwrite Trim, on the other hand, is a little different. When you perform a reductive trim using Overwrite Trim, you actually trim in black filler (video) or silence (audio) in place of the removed frames. In this way, all frames in the Timeline remain untouched (they don’t shuffle down), and you leave a gap in the sequence.

Overwrite Trim behaves this way only for reductive single-roller trims. Additive overwrite trims behave like dual-roller trims.

To use Overwrite Trim:

  1. In the Smart Tool, click Overwrite Trim.
  2. Select a transition in the Timeline.
    • To perform an A-side single-roller trim, click to the left of the transition.
    • To perform a B-side single-roller trim, click to the right of the transition.
  3. Perform the trim by clicking the appropriate Trim button. (Loop the playback before and after the trim, as necessary.)

Combining Ripple Trim and Overwrite Trim

Media Composer also allows you to enable both Ripple Trim and Overwrite Trim in the Smart Tool. Then, depending on where you place your pointer in the Timeline, you can enable one or the other.

To combine Ripple Trim and Overwrite Trim into one trim function:

  1. In the Smart Tool, click both the Ripple Trim and Overwrite Trim buttons.
  2. Do one of the following:
    • Place the pointer in the upper half of the segment to enable Overwrite Trim.
    • Place the pointer in the lower half of the segment to enable Ripple Trim.

You can also enable both Segment mode buttons, leaving all four on at once. Then, you can interact in a very dynamic way with both the segments and transitions in your sequence.

Scrubbing Audio While Trimming

You may want to hear the track as you’re trimming. You can do this by adding a simple step.

To scrub audio while you trim:

  1. Press the Caps Lock key, and solo the track you want to scrub.
  2. Trim using the Trim buttons or by dragging the trim rollers.
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