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Stefan slivinski lifesize video coding

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  • 1 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Video Coding: Current and Next

    Generation

    Stefan Slivinski

    Distinguished Engineer

    Lifesize Communications

  • 2 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Overview Video Coding Past, Present and Future

    Pretty Soon We Wont Need Video Compression

  • Video Compression

    Past, Present and Future

  • 4 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Types of

    Compression

    Lossless

    Original information is recoverable

    Lossy

    Information is lost

    Not specific to Video Compression

  • 5 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Lossy Video

    Compression

    Incapable of seeing high details

    More sensitive to light than it is to color

    can only fully perceive about 15fps

    Exploiting the limitations of the human

    visual system

  • 6 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Video

    Compression

    Spatial compression

    Temporal compression

    Discrete cosine transform (DCT)

    Quantization (lossy)

    Entropy coding

    Its all pretty similar

  • 7 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Video

    Compression Macroblocks

    Spatial and Temporal

    Quantization

    Entropy coding

    Past

    H.261 (1988)

    MPEG-2 (1995)

    H.263 (1996)

    MPEG4 Part 2 (1999)

  • 8 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Video

    Compression

    Multiple intra prediction modes

    Up to 16 motion vectors per macroblock

    4x4 and 8x8 fixed point transform

    Multiple block sizes include non-square blocks

    Adaptive Inloop deblocking filter

    Arithmetic entropy encoding

    Halfpel and quarterpel pixel interpolation

    Present

    H.264 / MPEG-4 AVC (2003)

  • 9 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Video

    Compression

    Very large block sizes (up to 64x64)

    4 transforms sizes 4x4, 8x8, 16x16, 32x32)

    coding tree units (CTU)

    Parallel processing tools adapted to multicore or hardware

    architectures

    Bit depths beyond 10bit, full chroma (unsubsampled)

    Future

    H.265 (2013)

  • Pretty Soon We Wont Need Video Compression

    --some guy I saw at a trade show

  • 11 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Need to answer

    3 questions

    How much resolution is enough?

    How much compression is

    enough?

    How much bandwidth is enough?

  • 12 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    How much resolution is enough?

  • 13 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    How much

    resolution is

    enough

    The average human eye can resolve 300 pixels per inch (ppi) at a distance of 12 inches

    The first retina iPhone (iPhone 4) had 326ppi

    A 60 4K television Has a ~73 ppi

    THX recommended viewing distance of 6-9

    At 6 the average human can resolve 40 ppi

    You would need to sit at a distance of 3.25 (39 inches) or closer to see all 73 ppi

  • 14 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    How much bandwidth /

    Compression is enough?

  • 15 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Availability of

    bandwidth

    20-30mbps in developed world

    Developing World much further behind

  • 16 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Video

    Compression 4Kp30 bandwidth

    H.265: 2-4mbps

    H.264: 4-8mbps

    MPEG4: 8-16mbps

    Video Communication Content

  • 17 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    How big is

    uncompressed

    video?

    4Kp30 3840 x 2160 @ 30fps @ 422

    3.9 gbps uncompressed

    720p60 1280x720, 60 fps @ 422

    844 mbps uncompressed

    CIF resolution 352 x 288 @ 30fps @ 422

    48.6 mbps uncompressed

    QCIF resolution 176 x 144 @ 30fps @ 422

    ~12 mbps uncompressed

  • 18 2014 Lifesize, a division of Logitech. All Rights Reserved. Confidential.

    Conclusion Television resolution peaking

    Bandwidth still poor

    Compression peaking in developed world

  • Questions?

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