3'5 Vector graphics

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3.5 Vector graphics

• Bézier curves
• recursive construction scheme

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P1,P2),(P4,P3))

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P2,P1),(P3,P4))

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P1,P2),(P3,P4))

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P2,P1),(P4,P3))

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P1,P3),(P4,P2))

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P1,P3),(P2,P4))

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P1,P4),(P2,P3))

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P1,P4),(P3,P2))

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3.5 Vector graphics

• Bézier curves
• different point sequences ((P1,P4),(P4,P3))

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3.5 Vector graphics

• Path/Curve rendering
• non zero winding number rule
• strokes
• joining styles

Bevel
Rounded
Mitre
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3.5 Vector graphics

• Combination model
• specifies the way drawing elements are combined
• layering, sequencing, e.g. PowerPoint objects

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Approximation
Filling
Rendering Y 2.5 X
Antializing
25
50
75
100
5
10
14

• 3D Models Chapman Chapman
• example for 3D fractals

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• 3D Models Chapman Chapman
• logical combinations

intersection
difference
union
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3.2 Colour

• Colour Mixing
• additive subtractive

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Pixel Graphics

• Modified Colour Palettes

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9. Video

• Video

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9.1 Basics

• 2 main standards
• Aspect Ratio 43
• NTSC Height 525, net 480 Width 640
• PAL Heght 625, net 576 Width 768
• NTSC (National Television Systems Committee)
• PAL (Phase Alternating Line)

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9.1 Basics
Interlaced mode Because of bandwidth limitations
the odd and even numbered line are displayed
interlaced. (non interlaced progressiv)

13579..
246810...
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9.1 Basics

• Computermonitor
• Movies, animations are non interlaced
• Low refresh rate sufficient
• Artefacts

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9.1 Basics

• Frequencies
• Flickereffect with frequencies less than 40 Hz
• 60 / 50 Hz per frame
• Color Mode RGB
• Horizontal frequencyPAL 25 625 15.625
  HzNTSC 29.97 525 15.734 Hz
• Bandwidth around 5MHz

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9.1 Basics

• Sampling
• NTSC 525 Lines pixels are higher than wide
• PAL 625 Lines pixels are wider than high
• 20 Mbyte/s
• Coding / Compression
• DV for Consumer Semiprofessional Video
• MPEG-2 for TV and DVD

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9.2 Compression

• Requirements
• Highly dependent on application
  (video-conference, VCD, )
• Screen size
• Color Space
• Refresh rate
• Audio-Video-Synchronization
• Capability to adapt to various parameters
• Two main concepts
• DV (Frame Based)
• MPEG (Block Based)

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9.3 MPEG
MPEG
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9.6.1 Video Editing, Basics

• Video Production
• 3 phases
• Pre-Production Skript, Storyboard,
  Productionsschedule
• Production production of image and audio streams
• Post-Production Cutting, Optimizing,
  Corrections, Effects
• Video-Tools are designed for Post-Production of
  digitized material.

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9.6.1 Video Editing, Basics

• Analog/Digital
• Analog (still) higher resolution,
  disadvantages loss of quality during copying
  processes, handling very complex but intuitiv
• Digital lossless, relativ simple but less
  intuitive handling, easy implementation of
  effectsdisadvantage memory usage, data transfer
  rates, lossy compression

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9.6.1 Video Editing, Basics

• Goals
• Digtal Post Processing
• Color correction
• Masking, Transparency
• Special effects, like audio positioning, video
  filters
• Title generation

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9.6.1 Video Editing, Basics

• Cutting, Composing from single clips, frames,
  animations
• Pre-Cut
• Cross fading
• synchronisation (PAL/NTSC-Rate!)
• Production of animations
• Technical prelimenaries
• Digitilization of Analog-Video by a Capture Card
• Direct transfer from camera with FireWire-Kabel