Discretion

Содержание и основные понятия

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Alterna · Chapter 9 · page 9.4
Discretion
Transforming continuous information into digital format: frequency, coding depth, channels, sound quality and images.
How do you write a sound or image for a computer? It's continuous, and the computer only works with numbers. We're sorting out in discreteization -- the process of cutting a continuous signal into separate accounts.
GEF
PIF
OGE No. 3.4
EEG No. 17
01
Analog and digital signal
Continuous vs Discretions with Fixed Values
GEF
OGE No. 3.4
Analog (continuous)
The signal changes smoothly, taking any value in the range. Examples: sound wave, temperature, pressure. Infinite number of possible values.
Digital (discreted)
The signal is presented by separate fixed-value accounts. The computer only works with discrete data, zeros and units.
Key concepts
Discretion
- breaking the continuous signal to separate points (calculations) at equal intervals.
Quantity
- rounding each count to the nearest level of the final set (defined by discharge).
~
Visualize signal discreteization
Discretion frequency:
20
the accounts
Discharge(s):
8
Show an analogy
Counting
Quantified
02
Going through audio files
How frequency, depth and channels affect quality and volume
GEF
PIF
OGE No. 3.4
EEG No. 17
The audio file formula
V = f × t × r × K / 8
f
— Discretion frequency (Hz),
t
- time (s),
r
- Detonation (bit)
K
- Number of channels, result - in
Bytes
♪
Audio file calculator
Frequency (Hz)
Detachment (beat)
Channels
Duration
min
Sec
03
Color and depth coding
Formula M = 2i: The relationship between depth and number of colours
GEF
PIF
Number of colours M = 2
i
Coding depth
i
(bit) determines the number of possible colours:
M = 2
i
For example, 1 bit = 2 colours (h/b), 8 bits = 256 shades, 24 bits=16,777,216 colors (True Color: 8R + 8G + 8B), 32 bits equals 16.7 million colors + 256 levels of transparency (8R + 8.G + 8.B + 8A).
◆
Color palette: 2 to 16 million colors
Deep:
24 bits = 16.7 million
Its Color (RGB)
R
G
B
#0080FF
R:0 G:128 B:255
04
Color depth in the image
How the image quality changes when bite is reduced
🖼
2 to 32 bits: Look at the difference
Select a random image and move the color slider. You can see how a small number of bits produces rough steps (posterization) and 24–32 bits is indistinguishable from the original.
Deep:
24 bits
Original (32 bits)
Color depth
05
Draw and dissect!
Draw an analog line and turn it into a discrete signal.
✎
Draw and dissect!
Discretion point:
30
06
Mini test
Five random questions from Bank 40.
0 / 500 XP
0 / 5
Press "Start Quest" for starters.