Video

  • Raw Video
  • YV12 - YCrCb(4:2:0)
  • RGBA - 32 bit Alpha Red, Green, Blue
  • WMV1: Windows Media Video 7
  • WMV2: Windows Media Video 8
  • WMV3: Windows Media Video 9
  •       Supports Simple and Main Profiles.
  •       Supports only progressive (non-interlaced) content.
  • WMVA: Windows Media Video Advanced Profile, non-VC-1
  • WVC1: Windows Media Video Advanced Profile, VC-1
  •       Supports Advanced Profile.
  •       Supports only progressive (non-interlaced) content.
  • H264 (ITU-T H.264 / ISO MPEG-4 AVC)
  •       Supports H.264 and MP43 codecs.
  •       Supports Base, Main, and High Profiles
  •       Supports only progressive (non-interlaced) content.
  •       Supports only 4:2:0 chroma subsampling profiles.

Audio

  • “1”. This is Linear 8 or 16 bit Pulse Code Modulation. Roughly speaking, this is WAV format.
  • "353" - Microsoft Windows Media Audio v7, v8 and v9.x Standard (WMA Standard)
  • "354" - Microsoft Windows Media Audio v9.x and v10 Professional (WMA Professional)
  • Supports full fidelity decoding of WMA 10 Professional Low Bit Rate (LBR) modes in the 32-96 kbps range.
  • Multichannel (5.1 and 7.1 surround) audio content is automatically mixed down to stereo.
  • 24 bit audio will return silence.
  • Sampling Rates beyond 48000 return an invalid format error code in same-domain and a 4001 in cross-domain scenarios.
  • "85" - ISO MPEG-1 Layer III (MP3)
  • "255" - ISO Advanced Audio Coding (AAC)
  • Supports Low Complexity (AAC-LC) decoding at full fidelity (up to 48 kHz).
  • High Efficiency (HE-AAC) encoded content will decode only at half fidelity (up to 24 kHz).
  • Multichannel (5.1 surround) audio content is not supported.

Unsupported Formats
The following formats are not supported:

  • Interlaced video content
  • Windows Media Screen
  • Windows Media Audio Professional
  • Windows Media Voice
  • Combination of Windows Media Video and MP3 (WMV video + MP3 audio)
  • Combination of WMV with AAC-LC

 关于Microsoft的若干Codec
Microsoft的AV文件后缀大多都是WMV，然后在大多数情况下，WMV文件是被封装在一个ASF 的container format中的。文件扩展名.wmv描述了一个使用WindowsMedia Video codec的文件。ASF container还可以包含数字版权管理。
WMV除了表示一种文件名后缀外，还表示一类codec，它也是在WMV 家族中公认的一种codec。这类codec的第一个版本是Windows Media Video 7(WMV 7)，4个字母的代号为WMV1，在1999年引入，是在Microsoft的MPEG-4 Part 2的实现的基础上作的。之后又出现了Windows Media Video (WMV 8，WMV2)，Windows Media Video 9(WMV 9，WMV3)。WMV9后来升级成为WVC1.
注意： 这里讲的都是codec，更WMP是没有关系的。
WMV家族中还有一类codec，称为Windows Media Video Screen (WMV Screen)，它用于捕捉屏幕内容，转换第三方屏幕抓取软件获取的Video为WMV Screen文件。它的一个应用就是computer step-by-step demonstration videos。
Windows Media Video Image (WMV Image) is a video slideshow codec。