In ___________, the level of one audio signal is reduced by the presence of another signal.

a piece of narration in a movie or broadcast, not accompanied by an image of the speaker.

___________ is the application of a constant amount of gain to an audio recording to bring the average or peak amplitude to a target level (the norm). Makes your audio sound louder.

(in film and video techniques such as chromakey) a blue (or green) background in front of which moving subjects are filmed and which allows a separately filmed background to be added to the final image.

____________ is also used to describe the process of calculating effects in a video editing program to produce final video output. Creates the final video file your audience will see.

.mp3

Compressed format, meaning the sound quality is "lossy" - mp3s are usually between 70-95% smaller than their equivalent "lossless" counterparts like wavs.

.aac

Audio encoding for lossy compression. Designed to be the successor of the MP3 format. Has better sound quality than MP3.

Data compression which removes elements in order to reduce the file size. Lossy recordings cannot be converted back to lossless as some of the original data is discarded during compression. MP3s are an example of a lossy audio file.

Compression which does not discard any data, meaning lossless compressed files can be converted back to the original state. WAVs are an example of a lossless audio file.