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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