PRB: Early Versions of Windows Media Player Stream Only the Lowest Bit Rate (832175)


The information in this article applies to:

  • Microsoft Windows Media Player for Windows XP Home Edition
  • Microsoft Windows Media Player for Windows XP Professional
  • Microsoft Windows Media Player 7.1
  • Microsoft Windows Media Services 9 Series

SYMPTOMS

New features were introduced with the Windows Media Format 9 Series Software Development Kit (SDK) with respect to multiple bit rate (MBR) content. Now when you create content by using Windows Media Encoder 9 Series, you can include both MBR audio and MBR video. Additionally, you can configure the MBR video to use different settings for the following items:
  • frame size
  • key frame interval
  • buffer length
  • frame rate
Although these new features optimize the experience for Windows Media Player 9 Series, if you use an earlier version of WMP, you may experience the following symptoms:
  • You see only the lowest bit rate that is provided in the MBR stream.
  • You cannot view the stream at all.
For example, if you use Windows Media Player 9 Series to connect to content that was created by using the Windows Media Encoder 9 Series, you see the best possible bit rate that is offered by that stream (assuming the network connection has sufficient bandwidth). However, if you connect to the same stream by using an earlier version of Windows Media Player, you see only the lowest possible bit rate for that stream.

CAUSE

This problem occurs because among the new extensions to the Windows Media Format that were introduced with Windows Media Player 9 Series was the stream prioritization object. This object sets the priority level for each stream. Based on design considerations, Windows Media delivers the lowest bit rate to reach users at the lowest possible connection rate.

RESOLUTION

For additional information about how to create MBR content for users of both Windows Media Player 9 Series and earlier versions of the player, click the following article number to view the article in the Microsoft Knowledge Base:

814676 PRB: Encoded Multiple Bit Rate Video Content in Windows Media Encoder 9 Series Does Not Stream from a Windows Media 4.1 Server

If you create MBR content and if you make sure that the settings that are listed in this article are the same for all bit rates, all users will be able to stream at the highest possible bit rate.

STATUS

This behavior is by design.
Modification Type:MinorLast Reviewed:1/16/2004
Keywords:kbDSWWMM2003Swept kbprb KB832175 kbAudDeveloper
©2004 Microsoft Corporation. All rights reserved.