Media File Types Explained
Posted by Ross Mann on Mon, Jun 28, 2010 @ 11:45 AM
The work you do creates big files. The work we do moves them to where you need them to go. But what do we know about these files? Why are they so big? What's in their name?
1. VOB: When you see the filename extension VOB, you're looking at a file that came from a DVD. They're commonly big, often 1GB. The format name stands for "Video Object", because VOBs contain the video part of a DVD. And as we know from watching DVDs, they usually have the highest quality of all digital video. More quality means more data, means larger file size.
2. ZIP: Named for the PKZIP file format developed in the 1980s, the ZIP file is an archiving and data compression format. When you see a ZIP file, you're usually seeing a collection of files that have been "zipped" into one large file. And they can get big. Photo collections commonly run in ZIP files.
3. MOV: This is another video file format, commonly of less visual quality than a VOB file. It's also called a "QuickTime" file, because it was created with Apple's video program QuickTime. MOV files can become very large depending on their purpose. If they're meant for high-quality playback, they can reach to nearly a GB (gigabyte) in size.
4. AVI: A Microsoft video file format, the name stands for Audio Video Interleave. Developed in the middle 1990s, the early standards for computer video used video and audio as separate parts, interleaving them together at playback. AVI was one of the earliest formats to combine both data types into one file. Generally of lower visual quality than MOV, a five-minute AVI will generally be smaller than a five-minute MOV.
5.WAV/AIFF: Audio files. WAV stands for Waveform Audio Format and AIFF for Audio Interchange File Format. These file types are much more similar to each other than is commonly found in the media file universe. They both encode audio in nearly the same way (the encoding technique is called PCM) and so tend to be of the same size for their running times. No top-end limit means these files can run to many hundreds of megabytes.