10.1 COMMON FILE FORMATS

When you’re woking in digital video, you will come across a range of different audio and video files, including:

    • WMV. A type of video compression developed by Microsoft. It is used in applications like Windows Movie Maker and is a common format of video file when using a computer running Microsoft Windows.
    • MP4. A multimedia container format which can contain both audio and video.
    • MOV. A format used by Apple’s Quicktime.
    • AVI. A multimedia container format developed by Microsoft which can contain both audio and video.
    • AIFF. An audio format co-developed by Apple Computer. If you record sounds as an AIFF file, they are usually uncompressed and suited to use in video editing software.
    • WAV. An uncompressed audio format developed by Microsoft and IBM. If you record sounds as a WAV file, they are usually uncompressed and suited to use in video editing software.
    • MP3. A type of audio compression developed by the Moving Pictures Expert Group. MP3s reduce the amount of data in the file, taking out sounds that most people can’t hear, therefore making the file much smaller. A sound compressed as an MP3 will typically be about a tenth of its original size. As an uncompressed WAV file, for example, a three minute song will be around 30MB. Compressed as an MP3, this file will only occupy about 3MB of space.
    • AAC. A type of audio compression developed by Apple. Commonly used on OS X and iPhones. Like MP3s, a sound is usually compressed to about a tenth of its original size.
    • WMA. A type of audio compression developed by Microsoft. Commonly used in Microsoft Windows and Zunes. Like MP3s, a sound is usually compressed to about a tenth of its original size.
    • AVIs and MP4s are container formats. This means they hold the audio and video tracks in a single document. The video will usually be compressed with compression algorithms like H.264.