Source Article Source: http://www.microsoft.com/windows/windowsmedia/cn/9series/codecs/video.aspx
Windows Media video 9
Compared with the Windows Media Video 8 codecs, Windows Media video 9 delivers a quality improvement of about 15% to 50% (the highest bit rate increases the quality), ensuring unparalleled video quality at any bit rate. For example, Windows Media video (WMV) 9 files are usually half the size of an equivalent MPEG-4 file.
Windows Media video 9 Advanced Profile
This is a new decoder provided along with the Windows Media Player 10, Windows Media Format 9.5 SDK, and the updated decoder installation package. The main features of Windows Media video 9 Advanced profile include improved intertwined support and Transmission Format independence. It works best on a computer running Windows Media Player 10, but it can also be used on Windows Media Player 7 or later. To use this decoder with the Windows Media Encoder 9 Series, you must install Windows Media Player 10. The advanced profile decoder displays an option in the decoder.With a previous version of the 9 series video codecs, the content generator provides progressive content with a low data rate to 1/3 of the MPEG-2 codecs and still delivers the same quality as the MPEG-2. With Windows Media video 9 Advanced profile, content generators and broadcasters can now achieve the same improvement in coding efficiency through intertwined content.
Transmission Format independence makes Windows Media video 9 Advanced profile available through systems that are not based on Windows Media, such as standard-based broadcast infrastructure (Transfer streams through a local MPEG-2) or wireless infrastructure (via RTP), or even a DVD. This feature integrates the Windows Media video 9 Advanced profile as the next generation of compression technology into emerging standard actions, such as those in SMPTE, DVB, ATSC, and DVD-Forum.
Windows Media video 9 Screen
Windows Media video 9 screen is an ideal choice for demonstration or demonstration of how to use a computer during training. This decoder can better process bitmap images and screen operations, even if the CPU configuration is relatively normal.
Windows Media video 9 Image
With this decoder, you can convert a static image to a full screen (640x480) video by means of translation and scaling. You can add a crossover and gradient transition to create a fully edited video editing effect. Then, the results can be transmitted at a low rate of 20 kilobytes (Kbps) per second. Files compressed in fixed bit rate (CBR) or single-step variable bit rate (VBR) mode can be easily shared because they are much smaller than the original image files.
Windows Media video 9 image version 2
With this new decoder, you can convert static images to videos by means of translation, scaling, and various conversion effects. You can combine these transitions with translation, scaling, and fade-in and fade-out to create effects with almost no limit. Then, the results can be transmitted at a low rate of 20 kilobytes (Kbps) per second. Files compressed in fixed bit rate (CBR) or single-step variable bit rate (VBR) mode can be easily shared because they are much smaller than the original image files. Note that Windows Media video 9 image version 2 is not compatible with earlier versions of this decoder.
Windows Media video 9 VBR Mode
In this mode, the Windows Media video 9 codecs can find more complex parts and allocate more bits (for example, sequences with more actions) to the desired part ), in this way, the optimal quality is achieved with a small average file size. Windows Media video 9 also supports peak VBR mode, so that you can specify the maximum bit rate allowed, Low Bit Rate connections, and devices (such as DVD players) can also take advantage of VBR.
