Managing Multimedia Redirection (All Topics)

About Multimedia Redirection

The Sun Ray Windows Connector's multimedia component redirects video streams to provide better performance for various models of Sun Ray DTU. For information about installing the multimedia redirection component, see How to Install the Sun Ray Connector Windows Components.

Performance can be improved for the following multimedia paths:

A standard RDP path is used for other media formats.

Supported Configurations

For the list of supported Windows operating systems, see SRS 5 System Requirements.

The multimedia redirection component supports Windows Media Player 10 and 11.

Multimedia Redirection Process

The following diagrams show how the multimedia redirection works for Sun Ray 1 and Sun Ray 2 DTUs.

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Adobe Flash Acceleration

The Adobe Flash Acceleration feature provides better performance of Flash display on DTUs. This feature is installed as part of the Multimedia Redirection component.

When Flash acceleration is enabled, Flash content is diverted from the default RDP channel and sent through a private channel to the Sun Ray DTU to achieve better performance and audio/video synchronization. The two main paths for Flash acceleration depend on the display mechanism of the Flash video content:

• DTU (XvEnc) - Flash content is decompressed and rendered in the DTU. This path yields the highest frame rates.

• X11/Xvideo - Flash content is decompressed on the Sun Ray server and is rendered by the X11 or Xvideo API before it is sent to the DTU.

By default, the DTU (XvEnc) path is enabled. You can use the -F option of the uttsc command to control which flash acceleration path is used.

Supported Configurations

For the list of supported Windows operating systems, see SRS 5 System Requirements.

Flash acceleration is provided in the following environment:

• Internet Explorer version 7 and 8 (32-bit)
• Adobe Flash 9 content with all Adobe Flash Players from versions 9 and 10

Other browsers and stand-alone applications leveraging the Flash runtime environment will not be accelerated and will continue to leverage existing RDP/X11 rendering.

How Does Flash Acceleration Work?

Flash animations are compressed on Windows and sent directly to the Windows Connector. This compression dramatically reduces the amount of data transferred between the Windows server and the Sun Ray server.

On Sun Ray 2 DTUs, the Flash display updates are sent by SRWC to the DTU to be decompressed and displayed. This process reduces the data transferred between the Sun Ray server and the DTU and does not affect the Sun Ray server CPU load. In Xinerama configurations, DTU decompression is not available.

On Sun Ray 1 DTUs, the Flash display updates are decompressed on the Sun Ray server and rendered through the Xvideo or X11 APIs.

In multihead configurations, Flash acceleration is available on all heads.

When Does Flash Acceleration Happen?

A maximum of four concurrently displayed Flash animations can be decompressed in the DTU (Sun Ray 2) or displayed over Xvideo (Sun Ray 1). If more than four Flash animations are displayed, the Flash animations beyond the first four are displayed using the X11 API.

On Sun Ray 2 DTUs, Flash animations are decompressed in the DTU as long as the combined size of all Flash animations is less than 1024x768. When this size is exceeded, the Flash animations that exceed the 1024x768 limit are displayed through Xvideo or, if more than four animations are displayed, through X11.

For example, if there are three animations and the first two combined animations are below the 1024x768 limit, the first two animations will be rendered in the DTU. If the third animation pushes the combined size above the limit, then the third animation will go through Xvideo and the first two animations will still render in the DTU. However, because the largest animations are always rendered through the DTU first, the rendering order might change. To use the same example, if the third animation pushes the combined size over the limit and the first animation is the smallest out of the three, then the smaller animation will go through Xvideo and the other two animations will go to the DTU, provided that their combined size is below the limit.

Note When calculating Flash animation combined sizes, add the pixel sizes of the animations together. For example, the combined pixel size of three animations at 640x480 is 921,600 pixels, which would be over the 1024x768 limit (786,432 pixels). (640 x 480) + (640 x 480) + (640 x 480) = 921,600 pixels

Note When the Flash animation size limit is exceeded, Xvideo or X11-based acceleration is used, with Xvideo given a priority. Depending on the Flash content that is being accelerated, X11-based acceleration or no acceleration at all might provide a better user experience than Xvideo-based acceleration. Typically, Xvideo-based acceleration is best when most of the Flash area is updated regularly, for example, for a movie where full frames are displayed one after the other. X11-based acceleration or no acceleration can provide a better user experience if only small areas of a large Flash area are updated.

The following diagrams also describe when Flash acceleration happens.

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H.264 Video Support

The best profile supported by the current Sun Ray hardware is Baseline, up to level 2.0. Certain videos encoded in the Main profile might play, however, the Sun Ray decoder does not support CABAC encoding or data partitioning, and cannot decode high-profile streams. Unsupported streams result in a black window or an error reported to the player.

For best results, video files should be encoded in Baseline profile at up to 352x288 pixels (CIF) and 15 frames per second (fps).

Related Topic

See About Multimedia Redirection for diagrams showing how H.264 support is provided on Sun Ray 1 and Sun Ray 2 systems.

VC-1 Video Support

Sun Ray 2 family DTUs support all Simple and Main VC-1 profiles, up to the following levels:

VC-1 Simple/Main profiles are compatible with the Windows Media Video 9 (WMV9) format and also use the hardware decoding in Sun Ray 2 series DTUs.

Note *.wmv files that are not VC-1 encoded cannot take advantage of accelerated playback.

Related Topic

See About Multimedia Redirection for diagrams showing how VC-1 video support is provided on Sun Ray 2 systems.

YUV Video Support

An accelerated path for YUV video delivery enables improved playback of video formats such as MPEG-1 and MPEG-2 by reducing the bandwidth required to deliver the decoded video to the Sun Ray DTU. The accelerated YUV path is used automatically so long as the correct software decoders are available for the video format required and the software is configured to make use of the XVideo extension. The following YUV formats are supported:

• Planar: YV12, I420
• Packed: UYVY, YUY2

H.264 or VC-1 video playback on a Sun Ray 1 DTU, which does not have a hardware decoding capability, uses software decoding and the accelerated YUV path.

Related Topic:

See About Multimedia Redirection for diagrams showing how YUV video support is provided on Sun Ray 1 and Sun Ray 2 systems.

How to Verify that Multimedia Redirection is Active

A small, context-sensitive Play button is displayed as an icon in the task bar when the multimedia redirection component is being used for video playback. Hovering the mouse over the icon displays the media type and size.

Troubleshooting Multimedia Redirection

Windows Media Player Error During Session Reconnection

If a Sun Ray Windows Connector session is relaunched or hotdesked while a supported media format clip is playing, a Windows Media Player error alert box might be displayed. If the message is displayed, the user must relaunch the clip from Windows Media Player.

Log Files

When multimedia enhancements are in use, status messages are logged in the following files:

• /var/dt/Xerrors (Solaris)
• /var/log/gdm/$DISPLAY.log (Linux)

Multimedia Status Messages

To enable logging, see How to Enable and Disable Log and Error Messages.

Note H.264 and VC-1 support on the DTU is not available for Xinerama sessions. In Xinerama sessions, video windows may be dragged from one DTU to another or may span multiple DTUs, but audio/video synchronization of H.264 and VC-1 support is limited to the primary DTU.  Videos cannot be synchronized between DTUs. H.264 and VC-1 videos are  rendered by the application in the same manner as they would be rendered on Sun Ray 1 DTUs.

Adobe Flash Acceleration Status Messages

To enable logging, see How to Enable and Disable Log and Error Messages.

When Flash acceleration is in progress, the following status messages identify the rendering mechanism used to display Flash content.

If Flash acceleration occurred (indicated by multimedia redirection icon) and no status messages are in the log file, then Flash display updates were decompressed on the Sun Ray Server and displayed through the X11 API.

Problem: Audio for a YouTube Video Is Out of Sync

Check whether the Sun Ray audio driver is set as the default:

1. From the Windows Desktop, choose Settings->Control Panel.
2. Click Sounds & Audio Devices.
3. Click the Audio tab.
4. If the Sun Ray RDP Audio Driver is not the default, select it and click Apply.
5. Close your browser and reopen it.