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.
SWF (Small Web Format/ShockWave Format) is a digital Adobe flash file format that stores vector-based animations, audios, and videos. Generally, it is used to stream media online, mostly browser-based games. Sadly, Adobe recently announced that they are ending Flash format support by the end of 2020 due to its shortcomings such as performance issues and lack of security.
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