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Flashcards in Definitions Deck (25)
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1
Q

Active Sources

A

Monitors, projectors

Emits wave lengths

2
Q

Passive Sources

A

Printed documents

Absorbs/ reflects light

3
Q

HSL

A

Hue
Saturation
Lightness

4
Q

Size of visible light

A

400-700nm

5
Q

Order of colour sensitivity

A

Green
Red
Blue

6
Q

Half-Toning

A

Uses dots

One colour per ink pass

7
Q

Dithering

A

Diffusion of coloured pixels

Uses different algorithms

8
Q

GIF

A

Graphical Interchange Format
Palette Colour
LZW compression
Transparency

9
Q

PNG

A

Portable Network Graphic
Lossless
True colour
Transparency

10
Q

TIFF

A

Tagged Image File Format
Adobe
Any image
Variety of compression

11
Q

JPEG

A
Joint Photographic Expert Group
True Colour 
1: Y Cr Cb
2: Chroma subsampled
3: DCT intensity -> frequency 
4: Quantised 
5: Huffman Compression
12
Q

Huffman Compression

A

Replaces frequently occurring pixel values with shorter code

13
Q

LZW

A

Replaces sequences in the data with a code that points to a dictionary

14
Q

MPEG

A

Moving Picture Expert Group
Temporal compression: removes data that doesn’t change
Spatial Compression: motion vectors
I frames, B frames, P frames

15
Q

FFT

A

Fast Fourier Transform

16
Q

Spatial Convolution

A

Smoothing/ sharpening

17
Q

Acoustics

A

When objects move it forces air to move causing compression in the molecules

18
Q

Wavelength

A

Distance travelled through one cycle of pressure

19
Q

Frequency

A

number of vibration cycles that pass a point in a second

20
Q

Bandwidth

A

Difference between max and min rate

21
Q

Amplitude

A

Strength/ power
Pressure displacement
Pascal

22
Q

Treble

A

Short waves
Easily blocks
Human hearing directionally sensitive
Surround sound

23
Q

Bass

A

Long wavelength
Easily bends
Human hearing not directionally sensitive

24
Q

Sampling

A

Low pass filtering

Nyquist

25
Q

Audio Compression

A
Threshold of hearing 
Amplitude masking 
Temporal masking 
Critical band 
Perceptual code