FCP 7: Putting Video Inside a Shape
Valentine’s Day is coming up, so I thought I would use it as the example for one of my favorite effects – putting video inside a shape. This effect is also called a “traveling matte.”
Here’s the finished effect, so you know where we are going. A girl is dancing on a bridge celebrating her love, indicated by the video inside the heart. (Thanks to Pond5 for supplying the clips for this tutorial.)
In this particular case, I created the heart in Photoshop. However, this technique works the same whether you create the shape in Photoshop or download an image you like from the Internet. I saved this image as a PNG as a single layer – no alpha channel (another word for “transparency”) is involved.
NOTE: If you have the choice, saving images as PNG or TIFF provides better quality than JPEG, so I tend to avoid JPEG. However, this technique works the same whether you are working with a PNG, TIFF, or JPEG. With one small change it will also work with PSD files, which I’ll indicate at the appropriate time.
Once the image is created / selected / downloaded it’s time to create the effect.
The order you build clips in the Timeline is important. In this case, the background image – the girl dancing – is placed on V1.
Since she dances exclusively on the left side of the frame, that gives me room on the right to put the shape.
Here’s the shape loaded into the Viewer. This is a single-layer PNG. There is no transparency anywhere in the clip. Edit the shape so it is stacked on top of the V1 clip, with the shape on V2.
Select the V2 clip and apply Effects > Video Filters > Key > Luma Key. This makes the white area of the shape transparent, revealing the dancing girl inside the heart.
Hmmm… We want just opposite effect – so double-click the V2 clip to load it into the Viewer, click the Filters tab at the top of the Viewer window, and change the Key Mode popup from “Key Out Brighter” to Key Out Darker.
Poof! The heart turns solid white and we see the dancing girl around the edges of the heart. Now, however, the heart is in the wrong place and too big.
Click the Motion tab in the Viewer and scale the shape to 80%. Adjust the position of the shape to the upper right corner – remember to keep the shape inside Action Safe, if this project is going to broadcast, cable, or DVD.
In the Browser, edit the video you want to insert into the heart to the Timeline into the V3 track.
NOTE: Because we want multiple images to appear on screen at the same time, we need to stack clips vertically.
Hmmm… we now have TWO problems: the video is the wrong aspect ratio and the video is not inside the heart.
This is where the very cool “magic sauce” comes in. Select the V3 clip and go to Modify > Composite Modes > Travel Matte – Luma.
Poof, again!! The V3 video now appears inside the heart.
NOTE: If you were working with a PSD file, where you retained the layers and their associated transparency information, you would select Modify > Composite Modes > Travel matte – Alpha. Aside from that one setting, the rest of this technique remains the same.
However, the video inside the heart is too small and off-center.
To fix this, double-click the V3 clip to load it into the Viewer, click the Motion tab and scale the image and adjust its position so it fits in the frame.
We don’t need to worry about shooting off the edges of the V3 image, because the only portion of the clip that we see is the portion that is inside the heart; shooting off the edges isn’t a problem – the heart masks them!
NOTE: Be careful scaling video images larger than 100% because they will tend to look grainy and soft.
However, this would look better with a drop-shadow behind the heart. But where do we put the drop-shadow? Answer: Not on any of the three existing tracks!
To add a drop shadow we need to create a copy of the heart shape and apply the drop shadow to the copy.
The easiest way to do this is to select tracks V2 and V3 and type Option+Up Arrow – this moves the selected tracks up one track. (Option+Down Arrow moves the selected clips down one track.
NOTE: This keyboard shortcut only works with video-only, or audio-only, clips. It won’t work with linked audio/video clips.
Then, while holding Shift+Option DRAG the V3 (Heart) clip down to V2. Shift+Option+drag makes a copy of whatever clip you are dragging.
Here’s the final clip alignment:
- V1: Background
- V2: Heart shape with drop shadow effect
- V3: Heart shape
- V4: Insert clip
Here are the drop shadow settings I used.
And this is our finished effect.
NOTE: You can animate the position of the heart by nesting (Sequence > Nest Items) V2, V3, and V4 – but NOT V1 – and animating it with keyframes.
This ability to insert video into a shape can be used for a single insert clip, or a variety of clips. Because the shape doesn’t change position or size, you can add a variety of different clips and have them all the look the same, as they are placed inside the shape.
You see this effect used in commercials all the time – and, now, you know how to create it, too.