This workflow is ideal for a four-corner pin in which the transformed or pinned image is the same size as the background frame (or reference patterns) it’s being tracked to. In the following example, a foreground image is pinned to a background clip of a picture frame.

1. Drag the playhead to the frame where you want to start the track analysis, then apply a Match Move behavior to the foreground object.

   Note: If you’re corner-pining a 2D group, ensure that the Fixed Resolution checkbox is selected in the Group Inspector.

2. In the Behaviors Inspector, click the Type pop-up menu, then choose Four Corners.

   

   Note: If you’re corner-pining a 2D group, ensure that the Fixed Resolution checkbox is selected in the Group Inspector. When you apply a Match Move behavior to a 3D group, the Four Corners option is not available. To corner-pin a 3D group, select the Flatten checkbox in the Group Inspector.

   In the Canvas, a tracker appears at each corner of the foreground object’s bounding box. In the Inspector, the default track list (Anchor and Rotation-Scale), is replaced with the Top Left, Top Right, Bottom Right, and Bottom Left trackers.

3. In the Canvas, drag each tracker to a corner of the background element (in this example, the corners of the picture frame).

   As you drag a tracker, a magnified inset appears to help you position each tracker.

   

   

   Note: You can specify a portion of a clip to be analyzed. For more information, see Define a range of frames for analysis.

4. Click the Analyze button in the HUD or Behaviors Inspector.

   The foreground element is pinned to the background element; four motion paths show the transformation occurring at each corner.

   

   To fine-tune the track (when the Type pop-up menu is set to Four Corners), you may need to make minor adjustments to the foreground element, such as modifying its scale or rotation. When you choose the Attach to Source option from the Transform pop-up menu in the Behaviors Inspector, you cannot transform the tracked object. To transform the tracked object, choose Mimic Source from the Transform pop-up menu.

5. If necessary, make minor adjustments to the foreground element (such as modifying scale or rotation) by doing the following:

   1. Click the Transform pop-up menu in the Behaviors Inspector, then choose Mimic Source.

      The default option in the Transform pop-up menu (Attach to Source) does not permit transformations of the foreground element.

   2. Open the Properties Inspector and make any necessary adjustments to the foreground object using the Scale slider, Rotation dial, or other controls.

   For more information on the Mimic Source and Attach to Source transform options, see Match Move controls.

If you need to position, resize, or rotate the foreground object to fit the background reference pattern (an angled TV screen or picture frame, for example), use onscreen controls to adjust the foreground object before you apply the Match Move behavior.

1. Select the foreground object.

2. In the toolbar, click and hold the 2D transform tools pop-up menu, then choose the Distort tool.

   

3. Move the playhead to the frame where you want to start the track analysis.

   Note: You define a range of frames to be analyzed. For more information, see Define a range of frames for analysis.

4. In the Canvas, drag each corner of the foreground object into the correct position.

   

   You can fine-tune the corner positions by adjusting the Position, Rotation, Scale, and Four Corner controls in the Properties Inspector.

   When you drag a corner in the Canvas, the Four Corner checkbox is selected in the Properties Inspector.

   Tip: You can lower the opacity of the foreground object to better see the reference points on the background clip. You may also want to disable snapping so the image you are adjusting does not snap to the Canvas guidelines. To turn snapping on or off, choose View > Snap or press N.

   

5. Apply the Match Move behavior to the foreground object.

   In the Canvas, a tracker appears at each corner of the foreground object. In the Inspector, the default track list (Anchor and Rotation-Scale) is replaced with the Top Left, Top Right, Bottom Right, and Bottom Left trackers.

6. If necessary, drag each tracker in the Canvas to further fine-tune its position, watching the magnified view in the Tracker Preview area of the Inspector.

   

   Important: To move the tracker positions independently of the foreground object, choose Mimic Source from the Transform pop-up menu in the Behaviors Inspector. When Attach to Source is chosen from the Transform pop-up menu, the foreground image is distorted when you drag the trackers in the Canvas.

7. Click the Analyze button in the HUD or Behaviors Inspector.

   The foreground object is pinned to the background element.

   Note: If you adjust the Four Corner parameter for a layer and then apply a Match Move behavior, the Four Corner parameter is applied in the behavior. If you delete the behavior, the four corner settings for the layer remain. If you reset the Match Move behavior, the four corner settings are reset.

If the Match Move pinning methods described above fail to yield a successful track, try four-point tracking using the Analyze Motion behavior. In this workflow, the four-point tracking data collected from the Analyze Motion behavior is loaded into a Match Move behavior to corner-pin a foreground object.

1. Go to the frame where you want to start the track and apply an Analyze Motion behavior to the background element.

   By default, a single tracker appears in the Canvas.

2. Drag the tracker (Track 1) to a reference pattern in the top-left corner of the background element.

   Note: For four-point analysis, the trackers should be positioned in a clockwise order, starting in the upper-left corner. This ensures the proper alignment of your element when the transformation is applied.

   

3. In the Behaviors Inspector, click Add to add a second tracker, then drag the second tracker (Track 2) to a reference pattern in the top-right corner of the background element.

4. Add another tracker (Track 3) and drag it to a reference pattern in the bottom-right corner of the background element.

5. Add another tracker (Track 4) and drag it to the reference pattern in the bottom-left corner of the background element.

6. Click the Analyze button in the HUD or Behaviors Inspector.

   The track is generated and its data is saved in the behavior.

7. Apply a Match Move behavior to the foreground element you want to corner-pin.

8. In the Match Move area of the Behaviors Inspector, click the Action pop-up menu (with the gear icon), then choose the Analyze Motion track.

   Doing so applies the Analyze Motion tracking data recorded in step 6 to the Match Move behavior.

9. In the Match Move area of the Behaviors Inspector, click the Type pop-up menu, then choose Four Corners.

   The four-point tracking data from the Analyze Motion behavior is applied to the foreground object.

   Note: In a Match Move behavior with four-point tracking, trackers are placed in the correct order (clockwise from the top left) in the Canvas after you choose Four Corner from the Type pop-up menu in the Behaviors Inspector. You can reorder the trackers by clicking the Top Left, Top Right, Bottom Right, and Bottom Left pop-up menus, then choosing new ordering options.

   

When you match move 3D groups that contain objects offset in Z space (depth), parallax is simulated. Parallax is the apparent shift of an object against a distant background caused by a shift in perspective, such as a change in camera position. You can disable this effect, if necessary, by doing the following:

• Select the Flatten checkbox for the tracked group in the Group Inspector.

  The parallax effect is removed.