Multimedia: Representation, Compression and Transmission

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Chapter 2

• Multimedia Representation, Compression and
  Transmission

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Contents

• 4. Video
• 4.1 Video Representation
• 4.2 Video Compression
• 4.2.1 General Concept
• 4.2.2 MPEG-1
• 4.2.3 Other MPEG Standards

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Video Representation

• Video is composed of a sequence of images (called
  frames or pictures).
• Frame rate (i.e., the number of frames per
  second) is large so that human eyes see smooth
  motion (e.g., it is 25 or 30 frames/sec for TV
  video).
• Video quality depends on (i) resolution and
  pixel depth of each frame and (ii) frame rate.

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Video Representation

• Two major standards for analog TV video
• 1. NTSC 30 frames/sec with 525 lines/frame.
• 2. PAL 25 frames/sec with 625 lines/frame.
• In HK, most video products support both NTSC and
  PAL.
• In this sector, when we refer to any video
  information, we refer to NTSC.

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Video Compression - Concepts
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Video Compression - Concepts
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Video Compression MPEG-1
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Video Compression MPEG-1
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Video Compression MPEG-1
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Video Compression MPEG-1
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Video Compression MPEG-1
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Video Compression MPEG-1
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Video Compression MPEG-1
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Video Compression MPEG-1
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Video Compression MPEG-1
Example
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Video Compression MPEG-1
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Video Compression MPEG-2
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Video Compression MPEG-4
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Video Compression MPEG-4
Example
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Video Compression MPEG-4
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Video Compression MPEG-4
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Video Compression MPEG-4