![]() The first version of the format was WMV 7 Screen. One of the uses for the format is computer step-by-step demonstration videos. They work best when the source material is mainly static and contains a small color palette. They can capture live screen content, or convert video from third-party screen-capture programs into WMV 9 Screen files. Windows Media Video Screen (WMV Screen) are video formats that specialise in screencast content. WMV used to be the only supported video format for the Microsoft Silverlight platform, but the H.264 format is now also supported starting with version 3. WMV HD mandates the use of WMV 9 for its certification program, at quality levels specified by Microsoft. The Microsoft Zune, Xbox 360, Windows Mobile-powered devices with Windows Media Player, as well as many uncertified devices, support the format. WMV is a mandatory video format for PlaysForSure-certified online stores and devices, as well as Portable Media Center devices. The format is not compatible with previous WMV 9 formats, however. It improves compression efficiency for interlaced content and is made transport-independent, making it able to be encapsulated in an MPEG transport stream or RTP packet format. The Advanced Profile in VC-1 is implemented in a new WMV format called Windows Media Video 9 Advanced Profile. The Simple and Main profile levels in WMV 9 are compliant with the same profile levels in the VC-1 specification. It is targeted towards high-definition video content, at resolutions such as 720p and 1080p. WMV 9 also introduced a new profile titled Windows Media Video 9 Professional, which is activated automatically whenever the video resolution exceeds 300,000 pixels (e.g., 528 px × 576 px, 640 px × 480 px or 768 px × 432 px and beyond) and the bitrate 1000 kbit/s. While all versions of WMV support variable bit rate, average bit rate, and constant bit rate, WMV 9 introduced several important features including native support for interlaced video, non-square pixels, and frame interpolation. Continued proprietary development led to newer versions of the format, but the bit stream syntax was not frozen until WMV 9. The first version of the format, WMV 7, was introduced in 1999, and was built upon Microsoft's implementation of MPEG-4 Part 2. Its main competitors are MPEG-4 AVC, AVS, RealVideo, and MPEG-4 ASP. Usage of the term WMV often refers to the Microsoft Windows Media Video format only. Windows Media Video (WMV) is the most recognized video compression format within the WMV family. Video compression formats Windows Media Video Diagram illustrating the relative frame sizes of several common video resolutions targeted by Windows Media Video 9 Professional, starting with 480p. One common way to store WMV in an AVI file is to use the WMV 9 Video Compression Manager (VCM) codec implementation. mkv), or AVI container format (extension. The ASF 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.Īlthough WMV is generally packed into the ASF container format, it can also be put into the Matroska container format (with file extension. While the ASF can encapsulate multimedia in other encodings than those the WMV file standard specifies, those ASF files should use the. Container format Ī WMV file uses the Advanced Systems Format (ASF) container format to encapsulate the encoded multimedia content. VC-1 became one of the three video formats for the Blu-ray video disc, along with H.262/MPEG-2 Part 2 and H.264/MPEG-4 AVC. ![]() The standard was officially approved in March 2006 as SMPTE 421M, better known as VC-1, thus making the WMV 9 format an open standard. In 2003, Microsoft drafted a video compression specification based on its WMV 9 format and submitted it to SMPTE for standardization. Microsoft also developed a digital container format called Advanced Systems Format to store video encoded by Windows Media Video. After standardization by the Society of Motion Picture and Television Engineers (SMPTE), WMV version 9 was adapted for physical-delivery formats such as HD DVD and Blu-ray Disc and became known as VC-1. The other compression technologies, WMV Screen and WMV Image, cater for specialized content. WMV consists of three distinct codecs: The original video compression technology known as WMV, was originally designed for Internet streaming applications, as a competitor to RealVideo. It is part of the Windows Media framework. ![]() Windows Media Video ( WMV) is a series of video codecs and their corresponding video coding formats developed by Microsoft. This article is about video encoding and decoding software. ![]()
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