Browse Definitions :
Definition

MPEG standards (Moving Picture Experts Group)

The MPEG standards are an evolving set of standards for video and audio compression and for multimedia delivery developed by the Moving Picture Experts Group (MPEG).

MPEG-1 was designed for coding progressive video at a transmission rate of about 1.5 million bits per second. It was designed specifically for Video-CD and CD-i media. MPEG-1 audio layer-3 (MP3) has also evolved from early MPEG work.

MPEG-2 was designed for coding interlaced images at transmission rates above 4 million bits per second. MPEG-2 is used for digital TV broadcast and DVD. An MPEG-2 player can handle MPEG-1 data as well.

MPEG-1 and -2 define techniques for compressing digital video by factors varying from 25:1 to 50:1. The compression is achieved using five different compression techniques:

  1. The use of a frequency-based transform called Discrete Cosine Transform (DCT).
  2. Quantization, a technique for losing selective information (sometimes known as lossy compression) that can be acceptably lost from visual information.
  3. Huffman coding, a technique of lossless compression that uses code tables based on statistics about the encoded data.
  4. Motion compensated predictive coding, in which the differences in what has changed between an image and its preceding image are calculated and only the differences are encoded.
  5. Bi-directional prediction, in which some images are predicted from the pictures immediately preceding and following the image.

The first three techniques are also used in JPEG file compression.

A proposed MPEG-3 standard, intended for High Definition TV (HDTV), was merged with the MPEG-2 standard when it became apparent that the MPEG-2 standard met the HDTV requirements.

MPEG-4 is a much more ambitious standard and addresses speech and video synthesis, fractal geometry, computer visualization, and an artificial intelligence (AI) approach to reconstructing images. MPEG-4 addresses a standard way for authors to create and define the media objects in a multimedia presentation, how these can be synchronized and related to each other in transmission, and how users are to be able to interact with the media objects.

MPEG-21 provides a larger, architectural framework for the creation and delivery of multimedia. It defines seven key elements:

 

  • Digital item declaration
  • Digital item identification and declaration
  • Content handling and usage
  • Intellectual property management and protection
  • Terminals and networks
  • Content representation
  • Event reporting

The details of various parts of the MPEG-21 framework are in various draft stages.

This was last updated in September 2005
SearchNetworking
  • virtual network functions (VNFs)

    Virtual network functions (VNFs) are virtualized tasks formerly carried out by proprietary, dedicated hardware.

  • network functions virtualization (NFV)

    Network functions virtualization (NFV) is a network architecture model designed to virtualize network services that have ...

  • overlay network

    An overlay network is a virtual or logical network that is created on top of an existing physical network.

SearchSecurity
  • encryption

    Encryption is the method by which information is converted into secret code that hides the information's true meaning.

  • X.509 certificate

    An X.509 certificate is a digital certificate that uses the widely accepted international X.509 public key infrastructure (PKI) ...

  • directory traversal

    Directory traversal is a type of HTTP exploit in which a hacker uses the software on a web server to access data in a directory ...

SearchCIO
  • chief digital officer (CDO)

    A chief digital officer (CDO) is charged with helping an enterprise use digital information and advanced technologies to create ...

  • security audit

    A security audit is a systematic evaluation of the security of a company's information system by measuring how well it conforms ...

  • chief transformation officer (CTO)

    Chief transformation officer is an executive role, often in the C-suite, that focuses on bringing about change as well as growth ...

SearchHRSoftware
SearchCustomerExperience
  • implementation

    Implementation is the execution or practice of a plan, a method or any design, idea, model, specification, standard or policy for...

  • first call resolution (FCR)

    First call resolution (FCR) is when customer service agents properly address a customer's needs the first time they call.

  • customer intelligence (CI)

    Customer intelligence (CI) is the process of collecting and analyzing detailed customer data from internal and external sources ...

Close