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May 11, 2020

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  • Alain Bouffioux - Philips Leuven 1 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Audio & Video Compression and its Application in Consumer Products

  • Alain Bouffioux - Philips Leuven 2 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Agenda • Introduction - The evolution of Audio/Video

    consumer products and the role of compression techniques.

    • Audio & Video compression principles • Audio compression • Video compression • Audio/Video synchronisation • The MPEG model and its situation in a

    communication context • Application to DVD (Digital Versatile Disc) • Application to DVB (Digital Video Broadcasting) • Conclusion

  • Alain Bouffioux - Philips Leuven 3 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Agenda • Introduction - The evolution of Audio/Video

    consumer products and the role of compression techniques.

    • Audio & Video compression principles • Audio compression • Video compression • Audio/Video synchronisation • The MPEG model and its situation in a

    communication context • Application to DVD (Digital Versatile Disc) • Application to DVB (Digital Video Broadcasting) • Conclusion

  • Alain Bouffioux - Philips Leuven 4 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Moore’s law

    Number of transistors per square inch doubles every 18 months

  • Alain Bouffioux - Philips Leuven 5 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Moore’s law today

    Cost of a transistor divided by one million in 30 years

  • Alain Bouffioux - Philips Leuven 6 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Moore’s law today (2)

    • “Self-fulfulling prophecy” (not automatic) = roadmap for the semiconductor industry

  • Alain Bouffioux - Philips Leuven 7 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Moore’s law today (3) • Roadmap for semiconductor industry

    = only certainty in the current undefined future • Moore’s law will continue to apply: 20 years

    – Economical limitation ? – Power consumption (Moore’s low in reverse direction) – Architectural gap between IP-blocks & application

    (middleware still more complex…) • Progresses in semiconductors

    = fuel the innovation = fuel the software revolution = fuel the wireless revolution

    (WLAN, WPAN, WBAN, …) • … • Examples:

    WBAN & sensors, RFID applications, camera to swallow, flexible display…

  • Alain Bouffioux - Philips Leuven 8 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The evolution of some CE products (1)

    ConsumerConsumer ComputerComputer

    CommunicationCommunication

    CDCD DCCDCC

    CDCD--ii

    DVDDVD

    STBSTB

  • Alain Bouffioux - Philips Leuven 9 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The evolution of our CE products (2) • The Residential Gateway (Set-Top-Box) as the link

    between the home and the world-wide information infrastructure.

    STB Home Network World-wide

    communication infrastructure

  • Alain Bouffioux - Philips Leuven 10 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The evolution of our CE products (3)

    • The STB (in home) as the gateway to various services. Local Server provides 2 kind of services: – Broadcast

    Analogue & digital TV, NVOD, PPV – Point-to-point (Home to local server)

    Home shopping, VOD, e-mail, Web browsing, PC connection...

    Network

    Local server

    Internet

    Local server

    Up to 800 homes

  • Alain Bouffioux - Philips Leuven 11 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The evolution of our CE products (4) • The STB as a key element of the home network

    To telephone Network

    Home Network

    Residential Gateway

    Computer

    DVD Jukebox

    Television

    Disk Recorder

    To satellite Network

    To cable Network

  • Alain Bouffioux - Philips Leuven 12 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The evolution of our CE products (5)

    • 3C Convergence - Progressive • New products combine all 3 functions • Products always more and more complex • Products have always new features • Lifetime of products is always shorter

  • Alain Bouffioux - Philips Leuven 13 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Factors enabling such evolution Compression is one among the various factors (all

    powered by semiconductor progresses) that enable multimedia.

    Software (methodology, user interface ...)

    International cooperation (interoperability & economy of scale)

    Disc capacity (DVD), communication going digital (Modems, xDSL, ATM ...)

    Multimedia

    Electronics (Memory capacity, clock frequency, µP architecture, ... --> decoding at low cost

    Audio/Video Compression (e.g. CCIR601 vs MPEG)

  • Alain Bouffioux - Philips Leuven 14 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    BUT !! • Convergence of technologies (consumer,

    communication, computer) All products combine all three technologies

    • BUT !

    • Divergence of applications – Home consumer, Multimedia phone, Camera, PDA,

    Office computer, Automotive… – High number of potential products

    Technology push Market pull (user centric approach)

  • Alain Bouffioux - Philips Leuven 15 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Agenda • Introduction - The evolution of Audio/Video

    consumer products and the role of compression techniques.

    • Audio & Video compression principles • Audio compression • Video compression • Audio/Video synchronisation • The MPEG model and its situation in a

    communication context • Application to DVD (Digital Versatile Disc) • Application to DVB (Digital Video Broadcasting) • Conclusion

  • Alain Bouffioux - Philips Leuven 16 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Compression in first A/V Products (1) • First Audio/Video products made compression without

    knowing it was compression. • How ?

    By removal of irrelevancies • Audio and Video characteristics

    Audio Video Spectral

    Sensitivity Good Bad

    Spatial Sensitivity

    Bad Good

  • Alain Bouffioux - Philips Leuven 17 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    Compression in first A/V Products (2) • Audio products

    From 2 to 7.1 channels are enough to provide the spatial resolution.

    • Video products Three colours (RGB) are enough to provide the spectral resolution.

  • Alain Bouffioux - Philips Leuven 18 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The need for more compression (1/5) • Audio: Compression needed in spectral domain • Bitrate of a stereo audio source (CD-DA encoding)

    Sampling frequency : 44.1 kHz Stereo 16-bit per sample Bitrate = 44100 * 2 * 16 = 1.41 Mbit/sec

    Audio waveform (time)

    time

  • Alain Bouffioux - Philips Leuven 19 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The need for more compression (2/5) • Video: Compression needed in spatial domain • Bitrate of a video source (CCIR 601 - 50 Hz countries)

    25 images per second YUV coding (Y: luminance - U,V : Chrominance) Y: 8 bit per pixel - U,V: 1 pixel on 2 coded, 8 bit per pixel Bitrate = (576*720)*25*16 = 166 Mbit/sec

    720 samples

    576 lines

    Video image

  • Alain Bouffioux - Philips Leuven 20 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The need for more compression (3/5) • Channels availables for AV transmission

    – Analog television channel (compatibility) Cable (bandwidth = 8 MHz) Satellite (Bandwidth = 30-40 MHz)

    ⇒ Capacity around 40 Mbit/sec

    – Compact disc (CD) For 74 min. play time : 1.41 Mbit/sec

  • Alain Bouffioux - Philips Leuven 21 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The need for more compression (4/5) • MPEG-1 target (Moving Picture Expert Group)

    (Video-CD : 74 min. constraints)

    But quality was judged too poor (about VHS quality)

    Compression

    Video : 166 Mbit/sec

    Audio : 1.4 Mbit/sec 1.4 Mbit/sec

  • Alain Bouffioux - Philips Leuven 22 A/V compression & Consumer Products - ULG Philips Digital Systems Laboratories 09/12/2004

    The ne