Motion Picture Experts Group (MPEG)

What is MPEG?

MPEG (Motion Pictures Experts Group) is a family of standards for audio and video compression and transmission. It is developed and maintained by the Motion Pictures Experts Group, a working group of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC).

There are several different types of MPEG standards, including −

• MPEG-1 −This standard is primarily used for audio and video compression for CD-ROMs and low-quality video on the internet.

• MPEG-2 −This standard is used for digital television and DVD video, as well as high-definition television (HDTV).

• MPEG-4 −This standard is used for a wide range of applications, including video on the internet, mobile devices, and interactive media.

• MPEG-7 −This standard is used for the description and indexing of audio and video content.

• MPEG-21 − This standard is used for the delivery and distribution of multimedia content over the internet.

MPEG uses a lossy form of compression, which means that some data is lost when the audio or video is compressed. The degree of compression can be adjusted, with higher levels of compression resulting in smaller file sizes but lower quality, and lower levels of compression resulting in larger file sizes but higher quality.

Advantage of MPEG

There are several advantages to using MPEG −

High compression efficiency − MPEG is a highly efficient compression standard and can significantly reduce the file size of audio and video files while maintaining good quality.

Widely supported − MPEG is a widely used and well-established audio and video format, and it is supported by a wide range of media players, video editors, and other software.

Good quality − While MPEG uses lossy compression, it can still produce good quality audio and video at moderate to high compression levels.

Flexible − The degree of compression used in an MPEG file can be adjusted, allowing you to choose the balance between file size and quality.

Versatile − MPEG can be used with a wide range of audio and video types, including music, movies, television shows, and other types of multimedia content.

Streamable − MPEG files can be streamed over the internet, making it easy to deliver audio and video content to a wide audience.

Scalable − MPEG supports scalable coding, which allows a single encoded video to be adapted to different resolutions and bitrates. This makes it well-suited for use in applications such as video-on-demand and live streaming.

Disadvantage of MPEG

There are also some disadvantages to using MPEG −

Lossy compression − Because MPEG uses lossy compression, some data is lost when the audio or video is compressed. This can result in some loss of quality, particularly at higher levels of compression.

Limited color depth − Some versions of MPEG have a limited color depth and can only support 8 bits per channel. This can result in visible banding or other artifacts in videos with high color gradations or smooth color transitions.

Non-ideal for text and graphics − MPEG is not well suited for video with sharp transitions, high-contrast text, or graphics with hard edges. These types of video can appear pixelated or jagged when saved as MPEG.

Complexity − The MPEG standards are complex and require specialized software and hardware to encode and decode audio and video.

Patent fees − Some MPEG standards are covered by patents, which may require the payment of licensing fees to use the technology.

Compatibility issues − Some older devices and software may not support newer versions of the MPEG standard.

How big is a MPEG file, in bytes?

The size of a MPEG file depends on the length, resolution, and complexity of the audio or video, as well as the level of compression used. In general, MPEG files can range in size from a few hundred kilobytes to several gigabytes.

As a rough estimate, a typical high-resolution video saved as a MPEG at a moderate level of compression might be around 500 megabytes per hour of video. However, the exact size of a MPEG file can vary significantly depending on the specific characteristics of the audio or video.

It's worth noting that the size of a MPEG file can be reduced by increasing the level of compression or by resizing the video to a smaller resolution. However, increasing the level of compression or resizing the video can also result in a loss of quality.