Irfan Ullah

Department of Information and Communication Engineering

Myongji university, Yongin, South Korea

Copyright © solarlits.com

o Introductiono MPEG-1o MPEG-2o MPEG-4o MPEG-7o MPEG-V

o Moving Picture Experts Group (MPEG)o Standards for audio and video compression and transmission

“Standard for lossy compression of video and audio”oCompresses at 1.5 Mbit/soParts

1) Systems (storage and synchronization)o Elementary streamso Program streamso Multiplexing

2) Video (compressed video content)o Color space to Y'CbCr (Y'=Luma, Cb=Chroma Blue,

Cr=Chroma Red)o Resolution/Bitrate (352x240, 352x288, or 320x240 but

supports 4095×4095, 100 Mbit/s)o Frame/pictureo Macroblocks (8x8 blocks for quantization)o Motion vectors (To remove some movement information

by motion estimation in encoder)

File extensions.mpg, .mpeg, .mp1, .mp2, .mp3, .m1v, .m1a, .m2a, .mpa, .mpv

o Forward Discrete Cosine Transform (FDCT)o 8x8 block pixel values into 8x8 indexed array of frequency

coefficient valueso DC coefficient and AC coefficients

o Quantizationo Finding the nearest multiple, and discarding the

remainder/moduluso Entropy coding

o Run-length encodingo Huffman Coding

Picture divided into 16x16 Macroblocks

8x8 subblocks of a MB

DCT

Quant.

4 Luma, 2 Chroma Blocks

Huffman

Coding

Bitstream00111001110111

I - Frame

Predictively coded Frame => encoded with reference to previous Frame

B - Frame

Intra coded Frame => encoded without reference to other Frame

P - Frame

B-Frame

FutureFrame

EntropyDecoding

Dequantize

IDCT

101000101

PrevFrame

+

AVG

3) Audio (compressed audio content)o Psychoacoustics (remove that sound which we can’t hear )o Channel Encoding

o Layer I (.mp1.m1a)

o Layer II (MP3, AAC)

4) Conformance testing o Provides two sets of guidelines and reference bitstreams

for testing

5) Reference softwareo C reference code for encoding and decoding of audio and

video

Apple released AAC

o Channel Mono and stereo Joint Stereo – intensity encoded Joint Stereo – M/S encoded for Layer 3 only Dual (two uncorrelated mono channels) Sampling rates: 32000, 44100, and 48000 Hz Bitrates: 32, 48, 56, 64, 80, 96, 112, 128, 160, 192,

224, 256, 320 and 384 kbit/s

o Applicationso Video CD (VCD)o Super Video CDo DVD-Videoo MP3 CDo Digital Video Broadcasting (DVB)o Digital Audio Broadcasting (DAB)o Digital audio devices

“The generic coding of moving pictures and associated audio information”oUp to 20Mbit/s and 60 frames per second

1. Systemo MPEG transport stream

o MPEG program stream

2. Video (Not less than 1 Mbit/s)

3. Audio o up to 5.1 multichannel

o More bitrate for MPEG-1 Audio Layer I, II and III

Encoding / Decoding

MSU Lossless Video Codec•Developed by the Graphics & Media Lab Video Group of Moscow State University

4. Describes procedures for testing compliance

5. Describes systems for Software simulation

6. Describes extensions for DSM-CC (Digital Storage Media Command and Control)

7. Advanced Audio Coding (AAC)

8. Dropped

9. Extension for real time interfaces

10. Conformance extensions for DSM-CC

11. Intellectual property management (IPMP)

MPEG-2 Elementary Encoder

MPEG-2 Elementary Encoder

Packetizer

Packetizer

Systems LayerMUX

Transport Stream

VideoSource

AudioSource

MPEG encoded streams

DataSource Packetizer

Applications

DVD-Video720 × 480, 704 × 480, 352 × 480, 352 × 240 pixel (NTSC)

720 × 576, 704 × 576, 352 × 576, 352 × 288 pixel (PAL)

Video peak 9.8 Mbit/s

Total peak 10.08 Mbit/s

Minimum 300 kbit/s

HDV (High-definition video)MOD and TOD (Recording formats for camcorders)DVB

For HDTV 720 x 576 x 50 frame/s progressive (576p50)

1280 x 720 x 25 or 50 frame/s progressive (720p50)

1440 or 1920 x 1080 x 25 frame/s progressive (1080p25 = film mode)

1440 or 1920 x 1080 x 25 frame/s interlace (1080i50)

“Multimedia content description standard”oEnables easier accessing, locating, navigating, searching, and managing audiovisual information.oAttaching metadata to multimedia contentoXML to store MetadataoMPEG-4 + MPEG-7 = MPEG-47

Extensible Markup Language (XML)“Set of rules for encoding documents in machine-readable form”

MetadetaDescriptive metadata

Describes information such as title, author, and abstract.

Structural metadata Relationships within and among objects

Administrative metadata Manage information resources through elements such as version

number, archiving date, rights management and preservation

Names of Metadata NISO MIX (Manage digital image collections)

DOI (Digital object identifier)

o Enables easier accessing, locating, navigating, searching, and managing audiovisual information.

o Attaching metadata to multimedia contento MPEG-4 + MPEG-7 = MPEG-47

Main elements

IBM MPEG-7 annotation tool Ricoh MPEG-7 movie tool Cannon MPEG-7 spoken content transcriptor

service Singingfish multimedia search

Applications

“Open framework for multimedia applications”oThe technology needed to support users to exchange, access, consume, trade or manipulate Digital Items in an efficient and transparent way.o Concepto Definition of a Digital Item (a fundamental unit of distribution and

transaction)o Users interacting with Digital Items

o Part 2: DIDL – representation of digital objects

o Part 3: DII – identification of digital objects

o Part 4: IPMP – enforcement of rights expressions

o Part 5: REL – declaration of rights expressions

o Part 7: DIA – transcoding based on contextual information

o Part 10: DIP – association of behaviors

“Media Context & Control”

o Part 1. Architectureo Part 2. Control Informationo Part 3. Sensory Informationo Part 4. Virtual World Object Characteristicso Part 5. Data Formats for Interaction Deviceo Part 6. Reference Software

MPEG Standards

Bit-rate Usage

MPEG-1 1.5Mbps VCD

MPEG-2 3-45 MbpsDVD, SVCD,

HDTV

MPEG-4 ScalableQuickTime,

DivX

H.264/AVCScalable,

½ orig. MPEG-4

AVCHD, Cable TV, YouTube,

…

H.265/HEVCScalable,½ H.264

Next generation