C1.3 Data storage and compression

Define storage capacity

Storage capacity is how much data the device can hold.

Show units of measurement and their value

State how you calculate file size on an image file

image file size = (image width × image height) × bit depth

State how to calculate the file size of a sound file

sound file size = sample rate × sample resolution × length of track

Define compression

Data compression is the process of encoding information using fewer bits than the original representation to reduce file size

State the benefits of compression

1. They take up less space on the storage device

2. Data transmission is faster

State the two types of compression

1. Lossless compression

2. Lossy compression

Define lossy compression

Lossy compression is a data encoding method permanently removes some data from the original source file.

Define lossless compression

Lossless compression is a data encoding method that does not lose any data from the original file.