Begin a new After Effects Composition. Title it “Alpha Matte Title” and set duration to 8 seconds. Click OK.
Import Video by double clicking in the Project Panel to then locate files on your computer.
Select the video you’ll be using as your background. Drag video into the composition timeline and scale to fit (TIP: Click Ctrl+Alt+F with the layer selected to fit the background to composition.)
Select the Text Tool, then type “ALPHA MATTE”. Scale and Align to center.
Precompose text layer (Ctrl+Shift+C). Then, double click to open composition in a new window.
Now in the text only composition, select the text layer and click Ctrl+D to duplicate. Delete “Matte” from the new text layer.
Duplicate the original text layer again, and now delete “Alpha.” Now delete the original text layer so now “Alpha” and “Matte” are two separate layers.
Select “Alpha” text. Create a mask by drawing a rectangle with the shape tool around the text.
Open Text layer in Composition timeline. Add an animator (the “playhead” button next to animate) and add “Position.” Adjust the text position so it’s completely above the Mask and not visible.
Open Range Selector. Make a Start Keyframe = 0% at the very first frame. Go forward to 1:15, and make a second Start Keyframe = 100%.
Select “Matte” text. Draw a mask just like we did for “Alpha”. Add an animator and set its position to be completely underneath the Mask.
Open Range Selector. At the very first frame, set the start value to 0% and make a keyframe. Go forward to 1:15 and make a second keyframe. Set its value to 100%.
Move the “Matte” text layer to 1 second in time to offset both text layers.
Locate video in the Project Panel you’d like to use for the top layer of text (in our case, the “Alpha” text.) Drag and place beneath the “Alpha” text layer. Resize video to fit the text.
Click “Toggle/Switches and Modes” to show the Track Matte menu. Open Track Matte menu for the video that’s underneath your text, and set it to Alpha Matte.
Locate the video you’d like to use for “Matte.” Repeat steps 14 and 15 for the “Matte” text layer as well.
Click on Toggle Switches and Modes and check the box for Motion Blur for “Alpha” and “Matte” Text layers.
Close out of the text composition. Now back into the Main composition, select the text layer, in Effects and Presets locate “Drop Shadow” and double click to apply.
Set Drop Shadow color to White, Opacity = 75%, Distance = 10, Softness = 10.
With the text layer still selected, click “S” to open scale properties. Set the scale at the first keyframe to 125%, and set scale to the final keyframe to 100%.
More Tutorials
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