alpha channel
 
 
 

A view of an image that represents the presence and degree of opacity of objects. The channel associated with each pixel determines the degree of opacity of that pixel.

In an alpha channel, areas that do not contain objects are black, areas that contain solid objects are white, and areas that contain partially transparent objects are a shade of gray.

In video production, the alpha channel is used to determine how one video image is laid over another.

When using Artisan tools, you can import image files created in other programs into Maya and if alpha channel values are available you can use them.

Also known as mask channel, matte channel.