Compositing is the combining of several images together and involves layering multiple video clips and effects on top of each other to create a new final image.

I'd like to introduce you to some important concepts and features used when compositing in Premiere Pro.

I'm in the Effects workspace.

In my Project panel, I've got a bin of Titles and a bin of Media, so I'll double click to open those in a new tab and choose the icon view.

This sequence already has clips on the V1 track, and two titles set above them on V2.

When we composite video, we're often stacking videos on top of each other in the Timeline to replace or blend selected parts of an image with elements from another image.

So, let's begin by placing a simple title on top of the first clip in the Timeline.

In the Titles bin, I'll double click the clip called Today to load it into the Source Monitor.

This title has transparency, but in order to see that in the Source Monitor, I have to turn on the Transparency Grid by selecting it from the Source Monitor Settings menu.

The checkerboard represents the transparent areas in this clip.

I'll put the playhead over the first clip in my sequence and press X to mark the duration of the clip on V1.

Now, I'll make sure my source clip is patched to V2 and press Overwrite.

I don't want the title to start right away, so I'll drag the edge to trim about a second from the head of the title on V2.

In the Program Monitor, the title on V2 appears in front of the background clip on V1 because titles created in Premiere contain an alpha channel.

An alpha channel defines areas of partial or complete transparency in an image.

I'll select both edges of this title on V2 by holding Command or Control on a PC as I click and drag through the clip.

Now I'll right click on one of the selected edges and choose Apply Default Transition to apply cross dissolves, so the title will fade up onto the background image.

So, you can see the alpha channel represented, I'll turn on the Transparency Grid in the Program Monitor then click the eye next to V1 to toggle off visibility for the background clips.

When I play through this title, you can see where the cross dissolve has applied transparency settings to some pixels in the image and those values are changing in each frame where the transition is active.

I'll make the V1 track visible again and continue compositing.

I want to blend part of another image into this background shot, beneath the title, so I'll click and drag the title up a track.

In my Media bin, I'll double click on the shot of the unicorn girl popping bubbles.

The Transparency Grid is still active in the Source Monitor, so this shot doesn't have transparent areas.

I'll have to use effects to create some.

This clip already has an inPoint set, so I'll put my Timeline playhead over the first clip and press X to mark the duration.

I'll double check source patching then press Overwrite.

I'll need to move this title a bit, so I'll select it on V3 and open the Essential Graphics panel.

Under Edit, I'll click the word Today... and a wireframe will appear around the text in the Program Monitor.

Before I reposition the title, I'll turn on Rulers under the Settings wrench then click and drag guides from the rulers to help me place the title.

Now I'll activate snapping so the titles will snap to the guides and drag on the word Today...

Back in the Settings menu, I can clear the guides or turn everything off.

Not all clips have an alpha channel, but by applying certain effects, you can create areas of transparency.

So, I'd like to introduce you to the opacity mask.

I'll select the clip on V2 and open the Effects Control panel.

Under Opacity, I'll choose Create Ellipse Mask.

With the word Mask selected, I'll head over to the Program Monitor to click and drag the mask into position.

By clicking on the edge points, I can expand the mask.

Dragging on this handle feathers the edge, creating semi-transparent pixels that help the two images blend nicely.

I'll also apply a cross dissolve at the end of the clip on V2 so the composite image blends smoothly with the next clip in the Timeline.

Back in my Media bin, I'll double click on what looks like an all-black frame, but it's actually a graphic that was saved with an alpha channel.

The Transparency Grid is still active in the Program Monitor so you can see that most of the image is transparent except for the small watermark logo at the bottom right.

When a graphic comes with an alpha channel, you can simply drop the clip on top of everything else in the Timeline and it's instantly positioned in the frame with all the other opaque images showing through the transparent areas.

Some graphics and video clips already contain alpha channels, but when they don't, there are many effects in Premiere that allow you to create and manipulate transparency.

Practice these essential compositing techniques so you can have more fun playing with effects and creatively combining your video images in Premiere Pro.