Mpeg
The Moving Picture Experts Group (MPEG) is a working group of ISO/IEC charged with the development of video and audio encoding standards. Since its first meeting in 1988, MPEG has grown to include approximately 350 members from various industries and universities. MPEG's official designation is ISO/IEC JTC1/SC29 WG11.
MPEG (pronounced EM-peg) has standardized the following compression formats and ancillary standards:
- MPEG-1: Initial video and audio compression standard. Later used as the standard for Video CD, and includes the popular Layer 3 (MP3) audio compression format.
- MPEG-2: Transport, video and audio standards for broadcast-quality television. Used for over-the-air digital television ATSC, DVB and ISDB, digital satellite TV services like DirecTV, digital cable television signals, and (with slight modifications) for DVD video discs.
- MPEG-3: Originally designed for HDTV, but abandoned when it was discovered that MPEG-2 was sufficient for HDTV.
- MPEG-4: Expands MPEG-1 to support video/audio "objects", 3D content, low bitrate encoding and support for Digital Rights Management. Several new (newer than MPEG-2 Video) higher efficiency video standards are included (an alternative to MPEG-2 Video), notably, Advanced Simple Profile and H.264/MPEG-4 AVC.
- MPEG-7: A formal system for describing multimedia content.
- MPEG-21: MPEG describes this future standard as a multimedia framework.
How MPEG works
The MPEG codecs use lossy data compression using transform codecs. In lossy transform codecs, samples of picture or sound are taken, chopped into small segments, transformed into a frequency space, and quantized. The resulting quantized values are then entropy coded.
The moving picture coding systems such as MPEG-1, MPEG-2, and MPEG-4 add an extra step, where the picture content is predicted from past reconstructed images before coding, and only the differences from the reconstructed pictures, and any extra information needed to perform the prediction, are coded.
MPEG standardizes only the bitstream format and the decoder. The encoder is not standardized in any way but there are reference implementations available for members that produce valid bitstreams. That means that any MPEG-4 decoder can decode any MPEG-4 material (of the same type) regardless of the encoder which produced that material.
This article is adapted from: wikiPedia.com.
Most popular articles
- Which Processor is Better: Intel or AMD? - Explained
- How to Prevent Ransomware in 2018 - 10 Steps
- 5 Best Anti Ransomware Software Free
- How to Fix: Computer / Network Infected with Ransomware (10 Steps)
- How to Fix: Your Computer is Infected, Call This Number (Scam)
- Scammed by Informatico Experts? Here's What to Do
- Scammed by Smart PC Experts? Here's What to Do
- Scammed by Right PC Experts? Here's What to Do
- Scammed by PC / Web Network Experts? Here's What to Do
- How to Fix: Windows Update Won't Update
- Explained: Do I need a VPN? Are VPNs Safe for Online Banking?
- Explained: VPN vs Proxy; What's the Difference?
- Explained: Difference Between VPN Server and VPN (Service)
- Forgot Password? How to: Reset Any Password: Windows Vista, 7, 8, 10
- How to: Use a Firewall to Block Full Screen Ads on Android
- Explained: Absolute Best way to Limit Data on Android
- Explained: Difference Between Dark Web, Deep Net, Darknet and More
- Explained: If I Reset Windows 10 will it Remove Malware?
My name is Dennis Faas and I am a senior systems administrator and IT technical analyst specializing in cyber crimes (sextortion / blackmail / tech support scams) with over 30 years experience; I also run this website! If you need technical assistance , I can help. Click here to email me now; optionally, you can review my resume here. You can also read how I can fix your computer over the Internet (also includes user reviews).
We are BBB Accredited
We are BBB accredited (A+ rating), celebrating 21 years of excellence! Click to view our rating on the BBB.