AP CSP

bit

smallest, fundamental unit of data (1 or 0)

How many numbers can you store with 8 bits? What is the range of those numbers?

256 numbers (0-255)

How may letters be stored in binary? Pictures? Sound?

Assign each letter a decimal number, convert decimal to binary. Give pixels hexadecimal code. Graph sound waveform.

How many distinct values can be represented with 2 bits?

4

byte

8 bits

What equation represents the highest number that can be represented by n bits?

$$2^{n}-1$$

What is the highest number than can be represented by 2 bytes?

65535

analog data

digital data

sampling

quantification

binary processing?

compression

finding repeated sequences in code and replacing them with shorter representations

Why use compression algorithms?

They save space by reducing file size.

Lossless compression

File size is reduced without losing any data through removing redundancy and using simplified organization.

bitmap

mapping pixels → bits (e.g. red pixels to 1 and white pixels to 0)

RLE (run-length encoding) compression algorithm

Lossless data compression algorithm that replaces consecutive identical pieces of data with (value, count).

Huffman coding algorithm

Lossless data compression algorithm that reduces file size by assigning binary codes to characters based on their frequency (frequent characters get shorter codes, and vice versa)

byte pair encoding

Lossy compression

File size is significantly reduced by removing less important data, affecting file quality.

How can you compress an audio file using lossy compression?

Discard the sounds that are out of the range of the human ear