RealVideo (RV) is a proprietary video format developed by RealNetworks and released in 1997. The RealVideo files are stored with the .rv extension. RealVideo is supported on multiple platforms like Windows, Mac, Linux, etc.
Usually, RealVideo is paired with RealAudio (RA) in the RealMedia (RM) container. It is suitable for streaming content over the internet and can be used for streaming live television for example.
The first version of RealVideo announced in 1997 was based on the H.263 format. RealNetworks continued to use the H.263 until the release of RealVideo version 8 when they switched to a proprietary video format.
RealVideo can be played from a RealMedia file or can be streamed over the internet by using the Real Time Streaming Protocol (RSTP). RSTP is used to manage the connection, to send the actual data, the Real Data Transport (RDT) protocol is used.
For real-time streaming, RealVideo uses a constant bit rate encoding. RealNetworks recently introduced a variable bit rate variant of RealMedia as RealMedia Variable Bitrate (RMVB). RMVB allows for the better video quality but is less suited for streaming as network capacity cannot be predicted.
Video compression formats and codecs
RealVideo is comprised of different video compression formats each identified by a four-character code. Given below is a list of video compression formats and the version of RealVideo that introduced them.