They really are the Moving Picture Experts (Group)
If you've read our section on audio formats, then MPEG will sound oddly familiar. Actually, if you've ever played a music or video file through your computer, then you've probably heard of MPEG. They're the Moving Picture Experts Group, after all.
Although the spectrum of MPEGs actually spans from MPEG-1 to MPEG-21, there are some major holes in that line. For the most part, A/V freaks will only recognize MPEG-1, MPEG-2, MPEG-3, and MPEG-4, which are all staples in the audio and video format realm. For the record, the only other two MPEGs in existence are MPEG-7 and MPEG-21, which can be, (very) basically, described as "multimedia frameworks". Today, they're not important.
MPEG: Everywhere you need it
MPEG-1, the very first in the line of excellent formats brought to use by the Moving Picture Experts Group, is worth exploring. MPEG-1 video is comparable to your average VHS tape, and that ain't very good. MPEG-1 audio layer 3 might sound familiar, and it should. MP3s make the world go 'round these days, and are at the heart of the booming digital-audio wave that has made the Apple iPod as important as a balanced breakfast.
Still, like AVI, age has treated MPEG-1 video well. It remains the most popular format for most computers and even VCD/DVD players.
So, why ever move beyond MPEG-1? Well, MPEG-1 only supports progressive images, and this reason is at the heart of the slow shift to MPEG-2.
Although some folks in the tech world still appear to have feelings for MPEG-1, most techies have moved on to the more recently developed MPEG-2. It's at the heart of the best DVD players, and is now the "go-to" format for most audio and video broadcast signals. This means that when you tune into cable or satellite, you're more than likely viewing MPEG-2 images.
Unlike MPEG-1, MPEG-2 supports both interlaced and progressive scan video streams. What this means is that MPEG-2 is not limited to reading images as frames, but may instead be presented as a field. Simply, MPEG-2 offers better picture quality. If you remember anything, remember that.
Because of the technological advancements of MPEG-2, it has gathered some significant attention from big-name tech companies. Owners of the patent for the technology include: Canon, Fujitsu, and Sony.
Like some other big names,
Sony owns a patent for MPEG-2
When talking about video, MPEG-3 truly is a continuance of the ongoing progression of image quality. Image quality began with MPEG-1 in the VHS class, moved to MPEG-2 and DVDs, and progressed into the MPEG-3 period of development. MPEG-3 was responsible for ushering in the exciting world of High Definition Television (HDTV).
But, stop the presses!
Although it offered a radical new way of viewing video, MPEG-3 has required a massive overhaul of a number of systems to show the upgraded visuals. Instead, technologists discovered that MPEG-2 could be manipulated to show HDTV, which essentially ended the immediate need for MPEG-3. How about that?
Note : Don't confuse MPEG-3 with MPEG-1 audio layer 3, otherwise known as MP3. One's a little used video format, and the other is an immensely popular audio format, used around the world by music pirates and iTunes aficionados.
MPEG-4 is the latest standard introduced in compressing and decompressing audio and video data. It was created in 1998, making it the youngest addition to the MPEG audio/visual family. The uses for MPEG-4 are immense, including, but not limited to, compact disc distribution, streaming media, and broadcast television. All of these applications profit from compressing the audio/visual stream.
Perhaps the best part of MPEG-4 is that many of the more intricate features are left up to the individual developer to create. In this period of technology's advancement, it seems particularly important that MPEG-4 has been made open source, for it is the reason for many other applications' growing success, i.e. Bit Torrent.
Explanations of a few audio codecs that employ MPEG-4 technology can be found in the sound section of this digital guide. These include OGG Vorbis, and FLAC, both lesser known but high-quality compression types. When speaking of video compression, some of the more notable codecs include XviD and Huffyuv.