If you have ever listened to an .mp3 file, watched a DVD movie, rented a video CD or watched a video online, then you have felt the benefits of the MPEG standard.
MPEG is actually Moving Pictures Experts Group - a group created by ISO (International Organization for Standardization). Founded in 1988, their task was to develop standards for encoded representation of both digital video and audio. In just a few years, in 1992, the MPEG-1 standard was approved by the group at a meeting in London - a standard which gave us the video CDs and MP3s. Later, in 1994, at a meeting in Porto, the MPEG group approved the MPEG-2 standard, which gave us DVDs, DVD players and the AAC standard, used for both television and audio encoding.
In 1999, the MPEG-4 standard was introduced and marked nothing less than a revolution of the video sharing online. It has been adopted as the de-facto standard for online videos and has remained such ever since.
Additionally, MPEG-7 and MPEG-21 have been created as standards for future development.
MPEG-1 is the first standard introduced by the MPEG group. Its aim was to provide a video playback of at least 1.5 Mbit/s and with a near VHS quality, as well as a digital audio playback with a quality similar to the CD audio quality. The results were soon to follow with the introduction of the Video CD, which allowed for a whole movie to be recorded on two simple CDs. Millions of Video CDs were produced, as well as Video CD decoders, both hardware and software, successfully replacing the VHS.
And while the Video CD was a big success, what was a real revolution was the MPEG-1 Layer 3 implementation - the MP3. It allowed for audio tracks to be easily ripped from an audio CD and then stored on a computer or recorded onto a new CD, creating custom compilations. Very soon, MP3 CD players were created, replacing the regular CD player, and after that - just MP3 players, which sported a small flash hard drive, allowing for songs to be easily replaced on the player without the need of creating a new CD in order to just add a few new songs.
MP3 was also adopted for online usage, since .mp3 files were small and required a simple decoding process. This made them perfect for use as an audio background for websites and inspired the creation of audio portals and stores.
The biggest advantage of the .mp3 file was its size. If you had a small web hosting account, or even a free ot low cost hosting plan account, you still could have .mp3 files stored there, since they were less than 5 MB for a regular song and didn't take much disk space.
Several years after the MPEG-1 standard was adopted, the MPEG group was ready to create another revolution in the audio and video world. And while it had already released the MPEG-2 standard, its main target was the video recording industry - creating the DVD video compression. The MPEG-4 standard was aimed at improving the current digital video formats, just like it did.
The MPEG-4 standard didn't “reinvent the wheel” as they say, but seriously improved the current digital video standards. Just like the MP3, it allowed MP4 encoded files to be much smaller and easier to decode, which allowed for video files to be easily embedded into websites, providing direct streaming to the user. This eliminated the need to have a private dedicated server if you just wanted to share some videos with the world - you could do it with a simple web hosting plan.
Another great advantage of the MP4 standard is that while the encoder itself is quite complex, the decoder is simple and one decoder can decode all kinds of MP4 encoded files without the need of serious updates.
The MPEG-4 standard allows for both audio and video compression, and an .mp4 file can contain both video and audio, only video or only audio. Though the file extension could remain the same - .mp4, additional file extensions were created and today an .mp4 file usually contains video, while audio MPEG-4 tracks are saved in an .m4a file.