video compression standards - history & introduction

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Video Compression Standards History & Introduction Champ Yen [email protected]

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Video Compression StandardsHistory & Introduction

Champ [email protected]

“Outline

▷ some concepts▷ MPEG-1/MPEG-2(H.262) ▷ MPEG4▷ H.264 (MPEG4 part 10)▷ HEVC/H.265▷ Q&A

Concepts

What is data compression?

lossy & lossless compression

Information Entropy

But What does Xi mean in Video Coding!?

Huffman Coding

Frame color format

http://commons.wikimedia.org/wiki/Category:YUVhttp://forum.doom9.org/showthread.php?t=167832

YUV444 YUV422 YUV420

Basic Sequence/Frame Structure

http://ride.chiariglione.org/MP1_inside.php

Motion Compensation

quality criteria: PSNR

Video Decoding Flow

EntropyDecode

inverseQuantization

inverseTransform

Inter / IntraPrediction

coef.data

coef.data

predictedframe

residual

decodedframe

sum & postproc

referenceframe

referenceframe

referenceframe

01011000101111

pred.info.

Video Encoding Flow

EntropyEncode

Quantization Transform

Inter / IntraPrediction

coef.data

coef.data

predictedframe

residual

sourceframesubstract

referenceframe

referenceframe

referenceframe

01011000101111

pred.info.

inverseQuantization

inverseTransform

coef.data

sum & postproc

residual

key-points of Video Coding

▷ Entropy Coding▷ Coding Unit▷ Quantization▷ Transformation▷ Inter/Intra Prediction▷ Post-Processing

MPEG-1/2

MPEG-1/2 overview

MPEG1/2 - Quantization

Quantization Matrix

http://en.wikipedia.org/wiki/MPEG-1

MPEG1/2 - zigzag scan

MPEG1/2 I/P/B frames

MPEG1/2 - Bitstream

MPEG-4

MPEG4 - block mode & inter prediction

MPEG4 - DC/AC prediction

MPEG4 vs MPEG1/2

H.264

H.264/AVC - block mode

H.264 intra-prediction

H.264 inter-prediction

½

¼

H.264 - MV prediction

H.264 - integer transform

http://mrutyunjayahiremath.blogspot.tw/2010/10/frq-transformation-and-quantization.html

What are the advantages of integer transformation?

H.264 - deblocking

Arithmetic Coding Concept

H.264 - CABAC

H.264 - NAL (Network Abstract Layer)

http://gentlelogic.blogspot.tw/2011/11/exploring-h264-part-2-h264-bitstream.html

Comparisons

HEVC/H.265

HEVC - Frame Structure

HEVC - block mode

CU - Coding UnitPU - Prediction UnitTU - Transform Unit

HEVC - intra prediction

HEVC - ⅛-pixel inter prediction

HEVC - MV prediction

HEVC - SAO

http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6324411

The concept of SAO is to reduce mean sample distortion of a region by first classifying the region samples into multiple categories with selected classifier, obtaining an offset for each category, and then addig the offset to each sample of the category, where the classifier index and the offset of the region are coded in the bitstream.

Miscs

Summary

▷ how to predict the frame▷ extract temporal/spatial

redundant▷ more and more fine-grained▷ new ideas/tools

Development Workflow

H.264 JM: http://iphome.hhi.de/suehring/tml/HEVC HM: http://hevc.hhi.fraunhofer.de/

ModifiedReferenceSoftware

ProprietaryImplementation

AnalyzeTool

verificationdata

goldendata

test casesbitstreams

References

● An Overview of MPEG-2http://literature.agilent.com/litweb/pdf/5966-1031E.pdf

● MPEG-4 natural video coding An overviewhttp://www.img.lx.it.pt/~fp/cav/Additional_material/MPEG4_video.pdf

● Overview of the H.264/AVC Video Coding Standardhttp://654lab.webstarts.com/uploads/csvt_overview.pdf

● MPEG Video Compression Basicshttp://www.springer.com/cda/content/document/cda_downloaddocument/9781441961839-c1.pdf

● http://www-i6.informatik.rwth-aachen.de/web/Misc/Coding/365/li/material/notes/Chap4/Chap4.3/Chap4.3.html● H.264 and MPEG-4 Video Compression, Iain E. G. Richardson● H.264 Specification

http://www.itu.int/rec/T-REC-H.264● Overview of the High Efficiency Video Coding (HEVC) Standard

http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6316136● HEVC Specification

http://www.itu.int/rec/T-REC-H.265

“Q & A

Thanks