Release 3.0

The Osprey Capture & Encoding Managerï¿½s Goal:

Recognizing that many customers may have already built their own custom multi-format encoding applications, SimulStream enabled drivers should transparently permit simultaneous multi-format encoding from a single device.ï¿½ However, for users without such custom applications, the task of starting and managing multiple encoding applications can be quite cumbersome.

The Osprey Capture & Encoding Manager (OCEM) is a single standalone, local encoding application designed specifically to demonstrate and enable multi-format encoding. OCEM was initially developed as a value-added software tool complementing Osprey SimulStream. SimulStream enables any number of applications to simultaneously access an Osprey device as if each application was the sole owner/user of the device.ï¿½ Thus, for example, any number of WindowsMedia Encoder applications as well as Helix Producer applications can be run at the same time on a single board. Each application session can be tuned for a specific audience profile. This can produce superior quality results compared to using the existing SureStream or MultiBitRate encoding techniques. SimulStream was also designed to scale with ever increasing processing speeds. As processing speeds increase, more unique streams and more formats will be able to be encoded at one time. This constantly improves workflow and increased encoding density for those doing large amounts of streaming. Currently OCEM supports encoding profiles for both Real and WindowsMedia formats although, consideration is being made to include additionalï¿½ formats. OCEM alsoï¿½ supports the ability to stream closed captioning text, provided you are using an NTSC video source that contains line-21 caption data.ï¿½ The OCEM currently does not have any support for decoding Pal Teletext or for PAL-CC.

While the Osprey Capture & Encoding Manager was designed to be used with SimulStream enabled Osprey products, it will work with non-SimulStream enabled Osprey boards. For example, you can use the captioning support in the Osprey Capture & Encoding Manager with just a single non-SimulStream enabled board to stream a single audio, video and text stream. When used with non-SimulStream boards only a single session can be created.

Osprey Capture & Encoding Manager Overview:

The Osprey Capture & Encoding Manager is a simple Graphical User Interface, or GUI, consists of two main panes .

In the left pane, Preview, the application displays a single video preview window sized to the resolution of the first video session. This pane also includes drop down selections for audio/video inputs and an area for audio gain control. The scrollable right hand pane, Sessions, shows detailed blocks for each session profile. Prior to starting to encode the user can add, delete and customize sessions.

All sessions are started and stopped at one time. A CPU monitor is also provided to indicate the current load on the machine.

The following snapshots are of the two main dialogs used to configure Windows Media and Real session profiles. This document serves only as an overview for the Osprey Capture & Encoding Manager and does not detail out specific descriptions of all options available. However, the options within the configuration dialogs should be familiar to those who have used the WindowsMedia or RealProducer applications.

In addition to streaming Audio and Video the Osprey Capture & Encoding Manager also allows for streaming text decoded from closed-captioned NTSC video sources. This feature is enabled if the user has installed Osprey Videoï¿½s Osprey Closed Caption Utility software. This software is available at:

ftp://ftp.ospreyvideo.com/pub/tools/captioning/

RealText

Once the Osprey Closed Caption Utility software is installed, the RealText Settings button on the main Configure New Session dialog for Real Video will be enabled. Pressing this button brings up the dialog below. Details for this dialog are included in the help installed with the Osprey Closed Caption Utility software.

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SAMI Text

Once the Osprey Closed Caption Utility software is installed the SAMIText Settings button on the main Configure New Session dialog for Windows Media will be enabled. Pressing this button brings up the dialog below.ï¿½ This dialog allows you to send the Closed Caption text to a separate file in SAMI format and/or embed the captions in the Windows Media file/player/format.

Captions embedded in a Windows Media file will display in a window below the video in Windows Media Player if Captions are turned on.ï¿½ To do this, click the view menu in Windows Media Player and then the ï¿½Now playing toolsï¿½ submenu and then the Captions option.ï¿½

There are several options to control captions embedded in a Windows Media file. The maximum lines to buffer configuration setting controls how many lines can appear at the same time in the caption window.ï¿½ The maximum hold time determines how long a caption may stay in the caption window.ï¿½ After the maximum hold time has passed the caption is erased even if no new caption is captured. The maximum time between captions specifies the amount of time that signals a new block of caption text.ï¿½ If two lines of caption text are separated by an amount of time greater than this interval then the new line will erase the old line.ï¿½ The old line will be scrolled instead of erased if the specified amount of time has not passed.ï¿½ All times are specified in milliseconds.

If you capture captions in a separate file then you should name the file with the same base name as the Windows Media file containing the audio/video.ï¿½ When you open a Windows Media file with Windows Media Player it will look for another file in the same directory with the same base name as the Windows Media file but with a .smi file extension.ï¿½ If the player finds such a file it will automatically open it to get captioning information.ï¿½ You can find more information on Synchronized Accessible Media Interchange (SAMI) files at the Microsoft Website.

Windows Media Custom Video Profiles

A Windows Media encoding profile encompasses:

ï¿½ Video encode format (i.e. Windows Media Video V7)

ï¿½ Audio encode format (i.e. Windows Media Audio V8),

ï¿½ Audio source format and encoded bitrate (i.e. 44Khz stereo encoded to 64kbps)

ï¿½ Target Audience Video Profile (i.e. DSL/Cable 384kbits)

ï¿½ Video resolution

The target audience video profile option specifies the:

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ï¿½ Profile Name

ï¿½ Frame rate

ï¿½ Key frame interval

ï¿½ Quality/Smoothness Tradeoff

ï¿½ Total Stream Bitrate

The Osprey Capture & Encoding Manager has the ability to customize the target audience video profile. The Advancedï¿½ button on the main Windows Media dialog brings up the advanced settings dialog. On this dialog, there is a Custom Bitrates button. This button brings up the target audience video profile editor. In this dialog, the user can add, delete and change profiles. For the most part these settings are straightforward, but we would like to provideï¿½ some further clarification on the Total Bitrate(Kbps) setting.ï¿½

The total bitrate box specifies the maximum stream data rate. A streamï¿½s rate is composed of the audio rate, the video rate and some additional overhead. The amount of overhead depends on various factors that are not detailed out in this manual. The Osprey Capture & Encoding Manager will take into account the audio bitrate and the overhead amount when settings the video bitrate. Thus, the audio/video bitrate is de-rated from the value entered on this page. The maximum video bitrate is then set to the de-rated amount minus the audio bitrate set on the main Windows Media configuration tab.

Configuration File

The Osprey Capture & Encoding Manager allows the user to set up various Sessions, Profiles, etc, and then save the program state so that it can later be reused. The configuration can be created, saved using the Session->Save Configuration option, and then loaded via the program GUI, using the Session->Open Configuration option. Or it can be used with Command Line Options, for use in batch processing.

Using a configuration file is also desirable if you use the machine primarily for more than one purpose. In such a case, you can set up each desired configuration and then save them for later use. For example, if you need to encode 3 separate Windows Media streams for later playback, and also encode 2 Real streams and 2 Windows Media streams for live broadcast, you can set up each desired configuration and then save them for easy set up at a later time.

These files are not human readable files, and thus are not editable through any method other than reloading in OCEM, changing the configuration and then saving the configuration.

Command Line Options

The Osprey Capture & Encoding Manager (OCEM) supports a command line interface.

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Syntax:

SimulStream.exe [/AutoStart] [Duration mm[:ss]] filename

ï¿½ ï¿½ï¿½ï¿½ï¿½ï¿½ /AutoStart -- start recording/sending to server as soon as loaded

ï¿½ ï¿½ï¿½ï¿½ï¿½ï¿½ /Duration mm[:ss] -- how long to record before closing down application. If no : is given, then the time is in minutes.

ï¿½ ï¿½ï¿½ï¿½ï¿½ï¿½ filename -- load the Configuration File at startup.