Is a media container format designed for streaming over the Internet. Used on popular video hosting sites. Video is usually stored in h.263 and h.264 formats, audio is a in MP3 or other less popular codecs. FLV-file format is a bit stream, which provides high-quality image even at low bit rates.
SPHERE (SPeech HEader Resources) is a file format defined by NIST (National Institute of Standards and Technology) and is used with speech audio. SoX can read these files when they contain μ-law and PCM data. It will ignore any header information that says the data is compressed using shorten compression and will treat the data as either μ-law or PCM. This will allow SoX and the command line shorten program to be run together using pipes to encompasses the data and then pass the result to SoX for processing.