Windows Media Video (WMV) is a compressed video file format for several proprietary codecs developed by Microsoft. The original codec, known as WMV, was originally designed for Internet streaming applications, as a competitor to RealVideo. The other codecs, such as WMV Screen and WMV Image, cater for specialized content. Through standardization from the Society of Motion Picture and Television Engineers (SMPTE), WMV has gained adoption for physical-delivery formats such as HD DVD and Blu-ray Disc.
A WMV file is in most circumstances encapsulated in the Advanced Systems Format (ASF) container format. The file extension .WMV typically describes ASF files that use Windows Media Video codecs. The audio codec used in conjunction with Windows Media Video is typically some version of Windows Media Audio, or in rarer cases, the deprecated Sipro ACELP.net audio codec. Microsoft recommends that ASF files containing non-Windows Media codecs use the generic .ASF file extension.
Although WMV is generally packed into the ASF container format, it can also be put into the AVI or Matroska container format. The resulting files claim the .AVI, or .MKV file extensions, respectively. WMV can be stored in an AVI file when using the WMV 9 Video Compression Manager (VCM) codec implementation. Another common way to store WMV in an AVI file is to use the VirtualDub encoder.
This container can optionally support digital rights management using a combination of elliptic curve cryptography key exchange, DES block cipher, a custom block cipher, RC4 stream cipher and the SHA-1 hashing function.
AVI:is a popular multimedia video format introduced by microsoft in 1992.
RMVB:is an extension of the RM format developed by RealNetworks.
MOV:QuickTime is a multimedia framework developed by Apple Inc.
DIVX:An attempt to create an alternative to video rental in the United States.
MPEG:formed to set standards for audio and video compression.
FLV:Flash Video is a multimedia format used to deliver videos over the Internet.
3GP:is a multimedia container format defined by the Third Generation Partnership Project.
ASF:is Microsoft's proprietary digital audio/digital video container format.
WMV:is a compressed video file format for several proprietary codecs developed by Microsoft.