MP2 Format Guide

Available Conversions

About MP2 Format

MP2 (MPEG-1 Audio Layer II or MPEG-2 Audio Layer II) is a lossy audio compression format that was widely used in broadcasting before being largely superseded by MP3 and AAC. Developed in the late 1980s and standardized in the early 1990s, MP2 became the audio standard for Digital Audio Broadcasting (DAB), Digital Video Broadcasting (DVB), and Video CD. The format offers a good balance between audio quality and compression, with typical bitrates ranging from 192 to 384 kbps for stereo audio. While MP2 has been largely replaced by more efficient codecs in consumer applications, it remains in use in professional broadcasting environments due to its simplicity, low latency, and widespread adoption in transmission infrastructure.

History of MP2

MP2 was developed by the Moving Picture Experts Group (MPEG) and members of the Digital Audio Broadcasting (DAB) project in the late 1980s. The codec was standardized as part of MPEG-1 in 1993 (ISO/IEC 11172-3) and later enhanced in MPEG-2 in 1995 (ISO/IEC 13818-3). The format was based on earlier work by the Fraunhofer Institute, Philips, CCETT, and other European research organizations. MP2 was designed specifically for broadcast applications where simplicity and error resilience were more important than maximum compression efficiency. In the mid-1990s, MP2 was adopted as the audio standard for DAB digital radio in Europe, DVB digital television, and the Video CD format popular in Asia. The format was also used in early digital satellite and cable television systems. Although MP3 (Layer III) offered better compression, MP2 remained preferred in broadcasting due to lower encoding/decoding complexity, lower latency, and better error concealment. Today, while MP2 has been superseded by AAC and other advanced codecs in many applications, it remains in use in legacy broadcasting infrastructure and some professional video production workflows.

Key Features and Uses

MP2 uses subband coding with 32 frequency subbands and psychoacoustic modeling to achieve compression ratios of approximately 6:1 to 8:1 compared to uncompressed audio. The format typically operates at bitrates between 192 and 384 kbps for stereo content, with 256 kbps being common for broadcasting. MP2 encoding and decoding are less computationally intensive than MP3, making it suitable for real-time broadcast applications and hardware implementations in the 1990s. The codec has lower encoding latency than MP3, which is crucial for live broadcasting and two-way communication systems. MP2 includes better error concealment mechanisms, making it more resilient to transmission errors in digital broadcasting. The format supports multiple channels and various sampling rates (32, 44.1, and 48 kHz). MP2's simpler algorithm makes it easier to implement in hardware, which was particularly important when computational resources were limited. The format does not support variable bitrate (VBR) encoding in most implementations, typically using constant bitrate (CBR) for predictable bandwidth requirements in broadcasting.

Common Applications

MP2 is primarily used in digital broadcasting systems. It serves as the standard audio codec for DAB (Digital Audio Broadcasting) radio in Europe, Australia, and other regions. The format is used in DVB (Digital Video Broadcasting) television systems for standard definition channels. MP2 was the audio format for Video CD (VCD), which was popular in Asia during the 1990s and early 2000s. Professional broadcast equipment and transmission systems continue to use MP2 for compatibility with existing infrastructure. The format appears in MPEG-1 and MPEG-2 video files, particularly in legacy video production and archival content. Some satellite radio systems and digital cable television networks still employ MP2 encoding. Non-linear editing systems and professional video production software support MP2 for compatibility with broadcast standards. Audio equipment in broadcasting studios, particularly in Europe, often includes MP2 encoding and decoding capabilities. While new broadcast systems are transitioning to AAC and other modern codecs, MP2 remains relevant in maintaining compatibility with existing digital broadcasting infrastructure and legacy content.

Advantages and Disadvantages