OGG is a free audio container format developed by Xiph.Org Foundation. Its unrestricted design offers efficient manipulation and streaming of high-quality digital multimedia. It multiplexes multiple streams for video, audio, text, and metadata. OGG has a filename extension of .ogg, although it can also come in .ogv, .oga, .ogm, .opus, and .spx.
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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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