M4V is a digital video container format developed by Apple Inc. It is pretty similar to the popular MP4 in terms of structure, but M4V files can sometimes be DRM protected. Today, M4V is the primary video format for iTunes Store videos and can multiplex together multiple audio and video data.
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Xvid is a cross-platform video codec for compressing video files. It can compress a video file at a more than 200:1 ratio. This, in return, makes it easier and quicker to transmit video files over the internet. Also, compressed videos take up less storage space. It compresses data using the MPEG-4 standard.
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