This chapter starts by providing an understanding of the significance of an alpha channel and some issues related to it. After realizing the alpha channel, this chapter deals with different keying and masking techniques. Following is the list of topics covered in this chapter:
Significance of the alpha channel
Blender's alpha modes
Layering concept and formula
Using the alpha channel when layering the foreground over the background with the Mix and Alpha Over nodes
Solving fringing issues while using the alpha channel with the Mix and Alpha Over nodes
Generating matte masks using the ID Mask node
Different ways to invert matte information
Edge filtering
Value and luminance
Concept of keying and what to inspect in the footage to be keyed
Understanding Blender's keying nodes