NSV (Nullsoft Streaming Video) is an audiovisual container format for streaming video data online. It was created in 2003 by Justin Frankel, while he was still working for Nullsoft. NSV only supports VP3 video codes and MP3 audio, although it was initially designed to stream all audio and video codecs. It is, in fact, the first format to allow users to make and stream live/recorded videos over the internet.
MP3 is a standard audio format developed by Moving Picture Experts Group and uses MPEG-1 and MPEG-2 standardizations. MP3 uses lossy data compression, meaning that it loses quality over time. This sound format comes with a .mp3 filename extension and is today the most common audio format on websites and multimedia players.
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