Windows Media Encoder 9 Series is a powerful tool for content producers who want to take advantage of the many innovations in Windows Media 9 Series, including high-quality multichannel sound, high-definition video quality, new support for mixed-mode voice and music content, and more. More Control and Flexibility Capture content with frame-accurate control. Protect live streams and initiate broadcasts. Author for a range of delivery scenarios including MBR streaming and CD/DVD. Unmatched Audio and Video Quality Create the clearest audio from multichannel to voice-only content. Encode to any levelfrom HD quality (1080i/1080p) to low data rate screen capture. Fine tune compression using new encoding modes. Extensibility and Automation Extend the Encoders functionality. Fully automate the encoding process. Includes 4 new utilities. Additional Information You can install the Windows Media Encoder 9 Series on a computer running either Microsoft Windows® XP or Windows 2000. The recommended configuration varies, depending on the encoding task, as described in the following paragraphs. To convert a file, the minimum configuration is a 266 megahertz (MHz) processor and 64 megabytes (MB) of RAM. The recommended configuration is a 500 MHz processor or higher, Windows XP, and 128 MB of RAM. To capture and broadcast audio and video files for 28.8 kilobits per second (Kbps) and 56 Kbps modems (using the Windows Media Audio 9 and Windows Media Video 7 codecs), the minimum configuration is a 300 MHz processor and 64 MB of RAM. For mid-bandwidth (100 Kbps to 500 Kbps) audiences, the recommended configuration is an 866 MHz processor or higher, Windows XP, and 256 MB of RAM. To capture and broadcast audio and video files for 28.8 Kbps and 56 Kbps modems, (using the Windows Media Audio and Video 9 Series codecs), the minimum configuration is a 1.5 gigahertz (GHz) processor and 64 MB of RAM. For mid-bandwidth (100 Kbps to 500 Kbps) audiences, the recommended configuration is a 1 GHz dual processor or higher, Windows XP, and 256 MB of RAM. To capture and broadcast an audio and video stream for high-bandwidth (500 Kbps through 2 Mbps) audiences (using the Windows Media Audio and Video 9 Series codecs), the recommended configuration is a 2 GHz dual processor or higher, Windows XP, and 256 MB of RAM.
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You need it when live streaming with Windows Media Server. Sometimes it has some problems with alien codecs and sometimes it's sloooow.
Does it's job effectively. Bit buggy on Vista with screenshot recording though.