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Video Over IP Products

Video Over IP Products. Video Compression. Why compression? High bit-rate video requires bandwidth. 1.5Gbps high-bit rate HD video streams cannot transmit over bandwidth- limited networks or even be stored on a DVD or Blu-Ray disc. This requires efficient video compression.

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Video Over IP Products

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  1. Video Over IP Products Video Compression

  2. Why compression?High bit-rate video requires bandwidth 1.5Gbps high-bit rate HD video streams cannot transmit over bandwidth- limited networks or even be stored on a DVD or Blu-Ray disc. This requires efficient video compression.

  3. Compression removes redundant bits (information) in an image Original image is represented by color information/bits as marked in alphabets and numbers. Compression complexity increases with higher number of colors. Compression removes redundant bit information from the image. Original image Compression Reconstructed image with less bits – color and resolution Shaded area represents the redundant color information. The size of the data in compressed form (C) relative to the original size (O) is known as the compression ratio (R=O/C) . Compression example for illustration purposes

  4. Intra-frame encodingLess complex and scalable Less encode/decode time/cycle; superior; scalable compression I I I B I B I P Intra-frame encoding Inter-frame encoding

  5. Compression Factors - for Broadcast Systems • Latency • Complexity • Cost • Quality

  6. Uncompressed over IP • Depends on application • Uncompressed video is not as scalable • Does not allow rapid deployment • Limits growth • GigE cannot be used for uncompressed HD • 10GigE = 6 x HD-SDI or 3 x 3G HD-SDI • Other overheads to be considered – FEC, wrappers • BUT bandwidth is increasing & cost is decreasing

  7. Compression • Flexible deployment of circuits • Effective use of bandwidth • Bandwidth can be dynamically allocated • This allows circuits to be switched on in real-time • Transport with no visible distortion: • 5-6 HD circuits over Gigabit Ethernet • 2 SD circuits over Fast Ethernet

  8. Which CODEC for Contribution? • Consider • Video Quality : 1 cycle, multiple cycle, concatenation • Cost : Complexity, Power, Bandwidth efficiency • Latency : Lower is better, especially for interactive applications • Standards : Stability? What about transport layer? • Availability : Who is providing? Who is using? What is the expected longevity of the CODEC? • Today MPEG-2 is still a viable solution but ultimately the main choices will be H.264 and JPEG 2000

  9. Video Compression - Options • MezzanineCompression • AggressiveCompression • Uncompressed VS902 VS901/2 VS904 Bandwidth 2-30Mbps 270Mbps – 3Gbps 50-150Mbps

  10. You only have one chance to make a good first compression You only have one chance to make a good “first compression” Once you’ve lost it, you’ll never get it back…

  11. Uncompressed • Good in metro / intra-facility • High bandwidth required – up to 3.2 Gbit/s per flow • Uncompressed HD doesn’t fit in GE • 10G interface cost – reducing • What benefit above visually lossless mezzanine? • Uncompressed video is not as scalable • Does not allow rapid deployment • Limits growth • HOWEVER bandwidth is increasing & cost is decreasing

  12. Mezzanine Compression • Light compression – up to 10:1 • Visually lossless or mathematically lossless options • JPEG 2000 or DIRAC or AVC-intra • Lower latency • Lower cost of both network and capital • Lower network bandwidth • Concatenation doesn’t degrade quality (JPEG2000) • Wavelet degradation is ‘gentle’ (J2K, DIRAC)

  13. High visual quality (compression ratio 6.5:1) JPEG 2000 Quality

  14. 20 encode/decode cycles at 6.5:1 JPEG 2000 Quality

  15. Aggressive Compression - H.264 • Advanced video compression standard • Underlying technology is similar to MPEG-2 • Equivalent quality at less than half MPEG-2 bit rate • Asymmetrical encoder/decoder complexity • Major advances in coding algorithms – bigger tool kit • Optimised for distribution: 5 – 15 Mbps for HD • Evolved to support high bit-rate professional applications • Contribution market penetration has been slow but gathering pace…

  16. Contribution Quality • Uncompressed – 100% of original • Mathematically lossless – 40% of original • Visually lossless – 10% of original (IFO) • Visually lossless – 2% of original (GOP) • Visible – 0.5% of original (distribution)

  17. Contribution Latency • Uncompressed – 1ms • J2K best of breed – 60ms • MPEG2 lowest – 200ms • H.264 lowest - 250ms • Other options include DIRAC, AVCintra

  18. End-to-end latency Highly dependant on bit rate & FEC setting transit decapsulate decode encode encapsulate 40ms – 3000 mstype/rate/mode/statmux 40ms – 100ms 1ms per 200km + 70us per router 10ms -1000msrate/FEC Typically sub 1ms

  19. Summary • One can choose to transport contribution quality video either uncompressed or compressed over IP • A scalable IP network infrastructure should not be limited by an un-scalable video format • Compression by nature allows video to be scaled to optimize bandwidth and ease network engineering • Compression provides flexibility while maintaining the required visual quality • JPEG 2000 is ideally positioned to fulfill the needs for high quality contribution feeds while providing low CAPEX and OPEX • H.264 is a good option for areas with less bandwidth available

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