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A New Coding Mode for Error Resilient Video PowerPoint Presentation
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A New Coding Mode for Error Resilient Video

A New Coding Mode for Error Resilient Video

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A New Coding Mode for Error Resilient Video

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  1. A New Coding Mode for Error Resilient Video EE368C Final Presentation Stanford University Sangoh Jeong Mar.8, 2001

  2. Outline • Use of Leaky Prediction + RD theory for Improved Error Resiliency • General Hybrid Video Codec • Proposed New Coding Mode • RD-Based Mode Selection • Experimental Environment • Results

  3. 176 (11MBs) MBs 0 1 16 8 144 (9GOBs) 2 5 6 8 1 16 7 Cr Cb 3 4 8 Y Block QCIF picture GOB # Data Units • GOB(Group Of Block)s, MB(Macroblock)s and Blocks - Example : For QCIF(9GOBs),

  4. Intra Compressed Bitsteam + Pe DCT Q Inter Input Video IQ IQ IDCT MCed MB IDCT Frame MC Memory MV Search ME Area Current MB Encoder Compressed Bitsteam Decoded Video Intra Frame Inter Memory MV MC Decoder General Hybrid Video Codec

  5. The Leaky-Inter Mode • Prediction Error • Leaky Prediction • Attenuates the energy of the prediction signal • Superimposed errors decay over time • Encoding of : Intra , Inter Reconstructed Frame Original Frame MB2 MB1

  6. Find the Reconstructed Frame Compute the Distortion Compute the Rate Involved Compute the Cost Choose the Mode with the Minimum Cost RD-Based Mode Decision • Cost Function & Decision Process • Intra Mode : • Inter Mode : • Leaky-Inter Mode : • Value of :

  7. RD-Based Coding Control Intra + Pe DCT Q Inter Input Video IQ IDCT IQ MCed MB1 IDCT Frame MC Memory 1 MCed MB2 MV Search ME Area Current GOBs loss and concealment MB No Feedback Frame Feedback Memory 2 Encoder Setup

  8. Encoder and Experiment • Encoder Software Used • H.263 Encoder V2.0 (TMN-8) • RD-Based Mode Decision Realized for Experiment • Error Resiliency Experiment • Effect of Leaky-Inter Mode - Case1 : Operation Without Errors, regarding values - Case2 : Operation With Errors, regarding values • Effect of Leaky-Inter Mode with Assumed Feedback - 3-Mode Operation with Errors, regarding an

  9. Conditions on Experiment • The Pattern of Errors • GOB Loss rate : 6.67% : Random Burst Loss of 3 GOBs / 5(average) decoded frames. • Same positions of errors applied to all experiments For Comparison • Assumption • Encoder knows the state of the decoder accurately • Error Concealment • GOB Concealment from Previous Frame for Errors

  10. L-Inter & Intra Result

  11. L-Inter & Intra Result (Error case)

  12. Resiliency in case of Feedback

  13. Conclusion & Future Work • Improved resiliency • Less coding efficiency • Not so helpful with accurate feedback • Further Experiment • Encoder knows only the region of errors of the decoded video as feedback information • Encode the region of errors with the Leaky-Inter Mode • Future work • Find the leaky-coefficient( ) methodically • Experiment with realistic transmission channels