Layers

A layer is a particular track that represents a certain type of footage. While not necessarily the footage itself, a layer is the space that the footage resides in. Understanding layers and how they interact with one another is a very important skill for both tennis, as well as digital editing in general.

One way to think of layers is like if you were making a cheeseburger. You'd have a bun, then the patty, ketchup, mustard, onions, lettuce, tomato, etc. in whatever order you see fit, then another bun. The order that you have each ingredient matters, but you can change them out individually.

Types of Layers

There are many different types of layers, many of which have sub-types and variants depending on the program you are using.

Video Layers

A Video Layer is the most important type of layer for tennis. It contains video (or photo) data from whatever footage you are using.

Audio Layers

Audio Layers are the next most important type of layer, which contain audio data from whatever footage you are using.

Null Layers

Null Layers are a special type of layer that has no properties of any kind; they exist in space as an invisible point. Null layers are useful in compositors (like After Effects) as they can be used to "group" layers together and tie them to a point in space. That way, rather than moving layers individually one-by-one, you can just move the null that they are attached to.

Adjustment Layers

Adjustment layers are special types of layers that on their own show absolutely nothing. However, you can apply "adjustments" (effects, etc.) which will apply said effect to all that is directly underneath of it.

Adjustment layers are commonly found in both video and photo editors (like Photoshop) to apply basic filters to the entire frame.

Layer Relationships

Parenting

Certain editors like Vegas and After Effects can create "parent-child" relationships between layers. A layer can be set as the "child" of another layer, at which point many of the child's attributes (usually dimensions but not effects) will follow that of the parent layer. This can be done recursively to create a large "family tree" of related layers, which is often necessary for managing large projects. Parenting is also how null layers get their use - creating a point that is invisible but still in control.