MPEG-4

 

General Information

 

 


MPEG is a set of international standards for audio and video compression.

MPEG-4 is a the newest MPEG standard, and is designed for the delivery of interactive multimedia across networks. As such, it is more than a single codec, and includes specifications for audio, video, and interactivity. Version 1 of the MPEG-4 spec was approved in 1999. Version 2 is expected to be finalized by the end of 2000.

The video component of MPEG-4 is similiar to H.263, but significantly advanced. The image quality has been significantly improved, and optimized for delivery of video at Internet data rates.

The MPEG-4 file format is based on QuickTime.

Microsoft's Windows Media Technologies provides an implmenentation of this codec which is stated to be standards compliant (as "ISO MPEG-4"). Older versions of Microsoft's MPEG-4 codecs (v1-v3) were produced while the standard was under development, and are not compliant.

Architectures Supported

 

Pros, Cons & Tips

 

 

Pros

  • Standard-based; should be widely intercompatible as it catches on
  • Very good quality at web bitrates

Cons

  • Not quite as efficient as some proprietary codecs

Ideal source material

Low-motion video

Supported color formats

YUV 4:2:0

Compression time

Asymmetric

Temporal compression?

Yes, including bidirectional (B) frames

Special features

MPEG-4 standard includes much more than a single video track (though not all players implement the extra features)

Encoder availability

Video encoder included in Windows Media

Decoder availability

Video decoder included in Windows Media

Algorithm

Discrete Cosine Transform (DCT) with Motion Prediction
based on H.263

Manufacturer

Many